10th Std Science Lesson Wise Questions in English – Part 2

10th Science Lesson 8 Questions in English

8] Periodic Classification of Elements

1. How many elements were discovered by the scientists by 1860?

a) 100

b) 5000

c) 60

d) 25

Explanation

By 1860, scientists had already discovered 60 elements and determined their atomic masses. They noticed that some elements had similar properties and hence arranged them into groups.

2. According to which property the elements were arranged in Mendeleev’s periodic table?

a) Atomic mass

b) Number of protons

c) Valence Electrons

d) All the above

Explanation

Mendeleev’s periodic table had some discrepancies, which were difficult to overcome. For example the atomic mass of argon (39.95amu) is greater than that of potassium (39.10 amu) but argon comes before potassium in the periodic table.

3. Which of the fundamental property was not known to the earlier scientists?

a) Number of Protons

b) Number of Electrons

c) Number of Neutrons

d) Number of chemical reactions

Explanation

The fundamental property turned out to be the number of protons in an atom’s nucleus, something that could not have been known by Mendeleev and his contemporaries.

4. Who discovered the atomic number of the elements?

a) Antoine Lavoisier

b) Johns Berzelius

c) Robert Boyle

d) Henry Moseley

Explanation

Henry Moseley, a British scientist in 1912 discovered a new property of elements called atomic number, which provided a better basis for the periodic arrangement of the elements. It is a well-known fact that atomic number of an element is equal to the number of protons or the numbers of electrons present in the neutral atom of an element.

5. Which of these refers to the modified periodic law?

a) The Physical property depends on the source of the elements.

b) The Elements are classified based on the number of chemical reactions.

c) The Physical and chemical properties are the functions of the atomic numbers of the elements.

d) The Chemical property of an element is depends on the number of electrons.

Explanation

The periodic law was modified to frame a modern periodic law which states that “The physical and chemical properties of the elements are the periodic functions of their atomic numbers”.

6. Which of these statements is true regarding the modern periodic table?

a) The Elements are arranged in increasing order of atomic numbers.

b) The Elements are arranged in periods and groups

c) It highlights the regular repetition of properties of elements.

d) All the above

Explanation

With reference to the modern periodic law the elements were arranged in the increasing order of their atomic numbers to form the modern periodic table. The modern periodic table is a tabular arrangement of elements in periods and groups highlighting the regular repetition of properties of the elements.

7. How many periods are in the horizontal row of the periodic table?

a) 7

b) 8

c) 4

d) 10

Explanation

The horizontal rows are called periods. There are seven periods in the periodic table.

8. How many elements are present in the first period of the periodic table?

a) 2

b) 1

c) 4

d) 3

Explanation

First period (Atomic number 1 and 2): This is the shortest period. It contains only two elements (Hydrogen and Helium).

9. What is the last element in the second period of the periodic table?

a) Hydrogen

b) Lithium

c) Neon

d) Helium

Explanation

Second period (Atomic number 3 to 10): This is a short period. It contains eight elements (Lithium to Neon).

10. Which of this element is not present in the third period of the periodic table?

a) Aluminium

b) Lithium

c) Sulphur

d) Argon

Explanation

Third period (Atomic number 11 to 18): This is also a short period. It contains eight elements (Sodium to Argon).

11. Choose the Incorrect statements about the fourth period of elements.

i) The fourth group of elements consists of atomic values from 20 to 45.

ii) The fourth group contains eighteen elements.

iii) Ten transition elements are present in the fourth group.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Fourth period (Atomic number 19 to 36): This is a long period. It contains eighteen elements (Potassium to Krypton). This includes 8 representative elements and 10 transition elements.

12. In which of this period the rubidium is classified in the periodic table?

a) Third

b) Second

c) Fifth

d) Fourth

Explanation

Fifth period (Atomic number 37 to 54): This is also a long period. It contains 18 elements (Rubidium to Xenon). This includes 8 representative elements and 10 transition elements.

13. How many Lanthanides are present in the sixth period of the modern periodic table?

a) 8

b) 14

c) 10

d) 4

Explanation

Sixth period (Atomic number 55 to 86): This is the longest period. It contains 32 elements (Cesium to Radon). This includes 8 representative elements, 10 transition elements and 14 inner transition elements (Lanthanides).

14. How many new elements were added in the seventh period recently?

a) 4

b) 10

c) 3

d) 7

Explanation

Seventh period (Atomic number 87 to 118): Like the sixth period this period also accommodates 32 elements. Recently 4 elements have been included by IUPAC.

15. How many groups of elements are classified in the periodic table?

a) 20

b) 15

c) 18

d) 12

Explanation

The vertical columns in the periodic table starting from top to bottom are called groups. There are 18 groups in the periodic table.

16. Which of these are called as inner transition elements?

a) Lanthanides

b) Actinides

c) Group 3

d) All the above

Explanation

The Lanthanides and Actinides which form part of Group 3 are called inner transition elements.

17. Which of this group does not have same number of valence electrons?

a) Group 18

b) Group 7

c) Group 8

d) Group 10

Explanation

Except ‘group 18’, all the elements present in each group have the same number of electrons in their valence shell and thus have the same valency. For example, all the elements of group 1 have one electron in their valence shells (1s1). So, the valency of all the alkali metals is ‘1’.

18. Which of these given identical property results in similar chemical properties of elements?

a) Valance shell configurations

b) Atomic weight

c) Physical property

d) Number of protons

Explanation

As the elements present in a group have identical valence shell electronic configurations, they possess similar chemical properties.

19. Which of the given are the physical property of elements?

a) Melting point

b) Density

c) Boiling point

d) All the above

Explanation

The physical properties of the elements in a group such as melting point, boiling point and density vary gradually.

20. Which of these group elements are unreactive?

a) Group 1

b) Group 20

c) Group 18

d) Group 12

Explanation

The atoms of the ‘group 18’ elements have stable electronic configuration in their valence shells and hence they are unreactive.

21. Assertion (A): The physical and chemical properties are known by the electronic configuration of the elements.

Reasoning(R): The electronic configuration of elements occurs repeatedly.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

The electronic configurations of elements help us to explain the periodic recurrence of physical and chemical properties.

22. Choose the correct statements.

i) Periodicity is the property of elements repeating at regular interval.

ii) All the atomic properties of elements are periodic.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Anything which repeats itself after a regular interval is called periodic and this behavior is called periodicity. Some of the atomic properties of the elements are periodic.

23. Which of these are the periodic properties of the elements?

a) Ionic radius

b) Electron affinity

c) Ionization energy

d) All the above

Explanation

Properties such as atomic radius, ionic radius, ionization energy, electronegativity, electron affinity, show a regular periodicity and hence they are called periodic properties.

24. What is the value distance between center of nucleus and valence electron?

a) Atomic radius

b) Atomic number

c) Atomic distance

d) Atomic affinity

Explanation

Atomic radius of an atom is defined as the distance between the center of its nucleus and the outermost shell containing the valence electron.

25. Choose the correct statements.

i) Isolated atom radius can be easily measured.

ii) Noble gas atomic radius is referred as covalent radius.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Direct measurement of the radius of an isolated atom is not possible. Except for noble gases, usually the atomic radius is referred to as covalent radius or metallic radius depending on the nature of the bonding between the concerned atoms.

26. Assertion (A): Metal atoms atomic radius value is known as metallic radius.

Reasoning(R): Metallic radius is measured as half the distance between the nuclei of adjacent atoms.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Atomic radius in metal atoms is known as metallic radius. It is defined as half the distance between the nuclei of adjacent metal atoms.

27. What is the atomic radius value of non-metallic elements?

a) Covalent radius

b) Metallic radius

c) Non-metal radius

d) All the above

Explanation

In non-metallic elements, their atomic radius is known as covalent radius. It is defined as half the distance between the adjacent nuclei of two covalently bonded atoms of the same element in a molecule.

28. What is the change in atomic radius value in the groups from top to bottom?

a) Decreases

b) Constant

c) Increases

d) Similar value

Explanation

Along the period, from left to right the atomic radius of the elements decreases whereas along the groups, from the top to bottom, the atomic radius increases.

29. Which of this value is increased along the period?

a) Valence electron

b) Protons

c) Atomicity

d) All the above

Explanation

Along the period, the shell number remains the same but the number of protons (i.e. atomic number) increases.

30. Which of these results in atomic size reduction?

a) Positive charges

b) Shrinking of electron clouds

c) Strong attraction of electrons

d) All the above

Explanation

More and more positive charges impose a strong attraction over the electrons and thus the electron cloud shrinks towards the nucleus, which results in the decrease in the atomic size.

31. Choose the correct statements.

i) Ions are formed by lose or gain electrons in an atom.

ii) A positively charged ion loses an electron.

iii) Anion gains an electron and it is negatively charged ion.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Ions are formed when an atom loose or gain electrons. When a neutral atom loses an electron, it becomes a positively charged ion called cation. The gain of an electron by a neutral atom forms a negatively charged ion called anion.

32. Which of this property is used to determine the behavior and structure of ionic solids?

a) Atomicity

b) Size of ions

c) Chemical property of ions

d) None of the above

Explanation

The size of the ions is important to determine their behaviors in solutions and the structure of ionic solids.

33. Choose the correct statements.

i) Size of a cation may be smaller than the neutral atom.

ii) Anion is always larger than the neutral atom.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

The size of a cation is always smaller than its corresponding neutral atom. But the anion is larger than its neutral atom.

34. Which of these increases the size of anion?

a) Decrease in positive charge

b) Increase in negative charge

c) Decrease in positive charge

d) Increase in negative charge

Explanation

The positive charge increases the size of the cation decreases. The negative charge increases the size of the anion increases.

35. How many electrons are lost /gained by sodium to form its cation?

a) Gain single electron

b) Gain two electrons

c) Lose one electron

d) Lose four electrons

Explanation

Lithium and sodium lose the single electron from their outermost energy level to form cations. The ions so formed are smaller because the remaining electrons are at inner cells and attracted more strongly by the nucleus.

36. Which of this group number represents the carbon family of elements?

a) 15

b) 2

c) 14

d) 17

Explanation

37. What is the value of the minimum energy required to remove an electron from an isolated gaseous atom?

a) Ionization enthalpy

b) Ionization measure

c) Ionization force

d) Ionized value

Explanation

Ionization energy is the minimum energy required to remove an electron from an isolated gaseous atom in its ground state to form a cation. It is otherwise called ionization enthalpy.

38. What is the unit of ionization enthalpy?

a) kJ/mol

b) k mol

c) J

d) kJ

Explanation

Ionization enthalpy: It is measured in kJ/mol. Higher the ionization energy, it is more difficult to remove the electron.

39. How the ionization energy increases along a period of elements?

a) Decrease in atomic size

b) Increase in valence electron

c) Decrease in proton value

d) Increase in velocity of electrons

Explanation

As the atomic size decreases from left to right in a period, more energy is required to remove the electrons. So, the ionization energy increases along the period.

40. Choose the correct statements.

i) The atomic size increases down the group of elements.

ii) Valence electrons are tightly bound down the group.

iii) Ionization energy increases down the group in a periodic table.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Down the group, the atomic size increases and hence the valence electrons are loosely bound. They require relatively less energy for the removal. Thus, ionization energy decreases down the group in the periodic table.

41. What is the value of amount of energy released from an isolated gas atom?

a) Electron affinity

b) Joule

c) Work

d) Enthalpy

Explanation

Electron affinity is the amount of energy released when an isolated gaseous atom gains an electron to form its anion. It is also measured in kJ/mol.

42. Choose the correct statements.

i) The Electron affinity decreases from left to right in a period of the periodic table.

ii) The ionization energy value decreases from top to bottom of a group in the periodic table.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Like ionization energy, electron affinity also increases from left to right in a period and decreases from top to bottom in a group.

43. Which of these statements is true regarding the noble gas?

a) It has fewer acceptances of electrons.

b) The valence electrons are not present in the orbit.

c) Electrons cannot be added.

d) Has maximum electron affinity value.

Explanation

Noble gases show no tendency to accept electrons because the outer s and p orbitals of noble gases are completely filled. No more electrons can be added to them and hence their electron affinities are zero.

44. Which of these values does not depend on electronegativity?

a) Bond energy

b) Ionization potential

c) Electron affinity

d) Valence electrons

Explanation

Electronegativity is based on various experimental data such as bond energy, ionization potential, electron affinity, etc.

45. Assertion (A): The Pauling scale is used to determine the electronegativity value.

Reasoning(R): The nature of bonding of the atoms is predicted by the Pauling scale.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Pauling scale is the widely used scale to determine the electronegativity, which in turn predicts the nature of bonding (ionic or covalent) between the atoms in a molecule.

46. Match the electronegativity value of elements.

A. Bromine i) 1

B. Sodium ii) 2.8

C. Chlorine iii) 4.0

D. Fluorine iv) 3.0

a) iv, iii, i, ii

b) ii, i, iv, iii

c) iii, i, iv, ii

d) ii, i, iii, iv

Explanation

Electronegativity of some of the elements are given below

F = 4.0, Cl = 3.0, Br = 2.8, I = 2.5, H = 2.1, Na = 1

47. What is the minimum electronegativity threshold value used to identify the character of elements?

a) 1

b) 1.7

c) 2.1

d) 7

Explanation

If the difference in electronegativity between two elements is 1.7, the bond has 50% ionic character and 50% covalent character.

48. What is the character of an element if the electronegativity difference value is greater than 1.7?

a) Alkali

b) Compound

c) Ionic

d) Covalent

Explanation

Elements with electronegativity difference less than 1.7, the bond is considered to be more covalent and if the difference is greater than 1.7 the bond is considered to be more ionic.

49. Choose the Incorrect statements.

i) The value of electronegativity along the period is increases from left to right.

ii) The electrons attracts more strongly as the nuclear charge value decreases along the period.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Along the period, from left to right in the periodic table, the electronegativity increases because of the increase in the nuclear charge which in turn attracts the electrons more strongly.

50. Which of this value is decreased by the increasing number of valence shell?

a) Electronegativity

b) Atomicity

c) Radioactivity

d) Conductivity

Explanation

On moving down a group the electronegativity of the elements decreases because of the increased number of valence shells.

51. Which of the following metals is not found in a human body?

a) Sodium

b) Mercury

c) Potassium

d) Calcium

Explanation

We use metals in our day to day activities. It is the utmost need to have some metals like sodium, potassium, calcium, iron, etc. in the human body. Deficiency of these metals affects the metabolic activities thereby causing diseases

52. Which of these properties of metals are analyzed by the metallurgical process?

a) Physical properties

b) Atom structure

c) Metal extraction methods

d) All the above

Explanation

Metallurgy is a science of extracting metals from their ores and modifying the metals into alloys for various uses, based on their physical and chemical properties and their structural arrangement of atoms.

53. Which of these is not involved in the metallurgical process?

a) Separation of ore

b) Metal production

c) Classification of ore

d) Metal refining

Explanation

A metallurgical process involves three main steps as follows:

(i) Concentration or Separation of the ore: It is the process of removal of impurities from the ore.

(ii) Production of the metal: It is the conversion of the ore into metal.

(iii) Refining of the metal: It is the process of purification of the metal.

54. Assertion (A): Ore is the mineral form of metal which can be economically extracted on a large scale.

Reasoning(R): Minerals may be a single compound or a complex mixture of metals.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Minerals: A mineral may be a single compound or a complex mixture of various compounds of metals found in the Earth.

Ore: The mineral from which a metal can be readily and economically extracted on a large scale is said to be an ore.

55. Which is referred as the impurity in a metal ore?

a) Gangue (Matrix)

b) Alkali

c) Slug

d) Flux

Explanation

Gangue or Matrix: The rocky impurity associated with an ore is called gangue or matrix.

56. Which of these is used to remove the impurities in metal extraction process?

a) Steam

b) Pure ore

c) Flux

d) All the above

Explanation

Flux: It is the substance added to the ore to reduce the fusion temperature and to remove the impurities. E.g. Calcium oxide (basic), Silica (acidic). If the gangue is acidic, then basic flux is added and vice versa.

57. Which of this product is formed by the reaction of flux and gangue?

a) Slag

b) Ore

c) Pure metal

d) Solvents

Explanation

Slag: It is the fusible product formed when a flux reacts with a gangue during the extraction of metals. Flux + Gangue → Slag

58. Which is added to remove the impurities as slag in smelting process?

a) Flux

b) Positive charge

c) Valence electron

d) Heat

Explanation

Smelting is the process of reducing the roasted metallic oxide from the metal in its molten condition. In this process impurities are removed as slag by the addition of flux.

59. How many types of separation methods are categorized based on the nature of ore?

a) 5

b) 3

c) 7

d) 4

Explanation

There are four major types of separation of ores based on the nature of the ore.

60. Choose the incorrect statements regarding the Hydraulic method?

a) Used for the heavier ores.

b) Based on the density difference principle.

c) Oxide ores use the hydraulic method.

d) Tinstone ore is separated by gravity separation method.

Explanation

Hydraulic (Gravity Separation) method

Principle: The difference in the densities or specific gravities of the ore and the gangue is the main principle behind this method.

Oxide ores are purified by this method. e.g. Hematite Fe2O3 the ore of iron. When the ore is heavier than the impurity, this method can be used.

61. Which of these ore is separated by the magnetic separation method?

a) Tinstone

b) Sulphides

c) Zinc blende

d) Haematite

Explanation

Magnetic separation method

Principle: The magnetic properties of the ores form the basis of separation. When either the ore or the gangue is magnetic this method is employed. e.g., Tinstone SnO2 the ore of tin.

62. Which of these is not true regarding the froth floatation method?

a) Depends on the wettability of ore with oil.

b) The ore or the gangue is magnetic.

c) Used for lighter metals.

d) Sulphide ores are concentrated by this method.

Explanation

Froth floatation

Principle: This process depends on the preferential wettability of the ore with oil (pine oil) and the gangue particles by water. Lighter ores such as Sulphide ores are concentrated by this method. e.g., Zinc blende (ZnS).

63. Which of this method is used for the pure form of ores?

a) Froth floatation method

b) Magnetic separation method

c) Leaching method

d) Gravity separation method

Explanation

Chemical method or Leaching method is employed when the ore is in a very pure form.

64. Identify the incorrect match.

A. Oxide Ore i) Cuprite

B. Sulphide Ore ii) Iron pyrite

C. Carbonate Ore iii) Galena

D. Halide Ore iv) Rock salt

a) i only

b) ii only

c) iii only

d) iv only

Explanation

Types of ores

65. How many types of metal extraction is categorized from metal oxides?

a) 2

b) 4

c) 3

d) 5

Explanation

Extraction of metal from metal oxide can be categorized into three types.

66. Match

A. Chromite i) Madurai

B. Lime stone ii) Tirunelveli

C. Tungsten iii) Cuddalore

D. Gypsum iv) Salem

E. Titanium v) Tiruchirappalli

a) iv, iii, i, v, ii

b) iii, v, ii, iv, i

c) ii, iv, iii, i, v

d) iii, v, iv, ii, i

Explanation

Lime stone: Coimbatore, Cuddalore, and Dindugul

Gypsum: Tiruchi and Coimbatore Districts

Titanium minerals: Kanyakumari, Tirunelveli and Tuticorin.

Chromite: Coimbatore and Salem district.

Magnetite:. Dharmapuri, Erode, Salem, Thiruvannamalai.

Tungsten: Madurai and Dindugal.

(Reference: mineral resources of Tamil Nadu-ENVIS Centre, Tamil Nadu)

67. Assertion (A): Metals possess a high lustre value.

Reasoning(R): All metals are solids at room temperature.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Physical properties

Physical state: All metals are solids at room temperature except mercury and gallium.

Lustre: Metals possess a high lustre (called metallic lustre).

68. Which of these metals have low density and hardness?

a) Potassium

b) Silver

c) Gallium

d) Zinc

Explanation

Hardness: Most of the metals are hard and strong (exceptions: sodium and potassium can be cut with a knife)

Density: Metals have a high density (exceptions: sodium and potassium are less dense than water).

69. Which of these metals vaporize at high temperature?

a) Gallium

b) Tungsten

c) Sodium

d) Mercury

Explanation

Melting point and Boiling point: Usually metals possess high melting and boiling points and vaporize only at high temperatures (exceptions: gallium, mercury, sodium and potassium).

70. Which of these metals cannot be beaten into sheets?

a) Silver

b) Copper

c) Mercury

d) Tungsten

Explanation

Malleability: Metals are usually malleable they can be beaten into thin sheets without cracking (except zinc and mercury).

71. Which of this metal is not a good conductor?

a) Silver

b) Gold

c) Copper

d) Tungsten

Explanation

Conduction of heat and electricity: Metals are good conductors of heat and electricity; silver and copper excel in this property (exception: tungsten)

Solubility: Usually, metals do not dissolve in liquid solvents.

72. Which of the following is not a chemical property?

a) Atomicity

b) Solubility

c) Valence electrons

d) Ions formation

Explanation

Chemical Properties

• Valence electrons: Atoms of metals usually have 1,2 or 3 electrons in their outermost shell.

• Formation of ions: Metals form Positive ions by the loss of electrons and hence they are electro positive.

• Discharge of ions: Metals are discharged at the cathode during the electrolysis of their compounds.

• Atomicity: Molecules of metals in their vapor state are usually monoatomic.

• Nature of oxides: Oxides of metals are usually basic.

73. Which of the statements are not true regarding aluminium?

a) Reactive metal.

b) It occurs in combined state.

c) Most abundant metal in earth’s crust.

d) Non-reactive metal.

Explanation

Aluminium is the metal found most abundantly in the Earth’s crust. Since it is a reactive metal, it occurs in the combined state.

74. Which of these is not an ore of aluminium?

a) Bauxite

b) Cryolite

c) Zinc

d) Corundum

Explanation

The important ores of aluminium are as follows

Ores of Aluminium Formula

Bauxite Al2O3.2H2O

Cryolite Na3AlF6

Corundum Al2O3

75. Which is the chief ore of aluminium?

a) Bauxite

b) Aluminate

c) Alumina

d) Graphite

Explanation

Bauxite is the chief ore of aluminium. The extraction of aluminium from bauxite involves two steps.

76. Which of this element is not involved in separation process of aluminium from bauxite?

a) Graphite

b) Caustic soda

c) Aluminium hydroxide

d) Sodium Meta aluminate

Explanation

The extraction of aluminium from bauxite involves the following steps:

Bauxite ore is finely ground and heated under pressure with a solution of concentrated caustic soda solution at 150° C to obtain sodium meta aluminate. On diluting sodium meta aluminate with water, a precipitate of aluminium hydroxide is formed. The precipitate is filtered, washed, dried and ignited at 1000°C to get alumina. 2Al (OH)3 Al2O3 + 3H2O

77. Which of this reduction produces aluminium in Hall’s process?

a) Oxygen

b) Electrolyte reduction

c) Electrochemical

d) Aqua reduction

Explanation

Electrolytic reduction of alumina –Hall’s Process

Aluminium is produced by the electrolytic reduction of fused alumina (Al2O3) in the electrolytic cell.

78. Which of this element is not related to the Hall’s process?

a) Graphite rods

b) Pure alumina

c) Steam

d) Fluorspar

Explanation

Cathode: Iron tank lined with graphite

Anode: A bunch of graphite rods suspended in molten electrolyte.

Electrolyte: Pure alumina+ molten cryolite + fluorspar (fluorspar lowers the fusion temperature of electrolyte)

79. What is the overall reaction of the Halls process?

a) 2 Al₂O ₃ → 4 Al +3 O2↑

b) Al + H₂O → Al + H₂↑

c) Al ₂ + N ₂ → 4 Al + NO₂↑

d) Al₂O₄→ 4 Al +3 H₂O↑

Explanation

Temperature: 900 – 950 °C

Voltage used: 5-6 V

Overall reaction: 2 Al2O3 → 4 Al +3 O2↑

80. Which of these combines with graphite to form CO2?

a) Hydrogen

b) Nitrogen

c) Oxygen

d) Carbon

Explanation

Aluminium is deposited at the cathode and oxygen gas is liberated at the anode. Oxygen combines with graphite to form CO2.

81. Which is not a physical property of aluminium?

a) Low density

b) Heat and Electricity conductor

c) Melting point is 100°C

d) White silvery metal

Explanation

Physical Properties of Aluminium

• It is a silvery white metal

• It has low density (2.7) and it is light

• It is malleable and ductile

• It is a good conductor of heat and electricity.

• Its melting point is 660 °C.

• It can be polished to produce a shiny attractive appearance.

82. Choose the correct statements.

i) Aluminium reacts with dry air and produces hydrogen.

ii) Aluminium forms its oxide and nitride when heated at 800 °C

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Reaction with air: It is not affected by dry air. On heating at 800 °C, aluminium burns very brightly forming it’s oxide and nitride.

4 Al + 3 O2 → 2 Al2O3 (Aluminium oxide)

2 Al + N2 → 2 AlN (Aluminium nitride)

83. Assertion (A): Aluminium reacts with steam and produces hydrogen.

Reasoning(R): Water does not react with aluminium because of the oxide layer.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Reaction with water: Water does not react with aluminium due to the layer of oxide on it. When steam is passed over red hot aluminium, hydrogen is produced.

2 Al + 3 H2O → Al2O3 + 3 H2↑

84. Which of these reacts with aluminium and produces aluminates?

a) Acids

b) Alkalis

c) Base

d) Metals

Explanation

Reaction with alkalis: It reacts with strong caustic alkalis forming aluminates.

2 Al + 2 NaOH +2 H2O → 2 NaAlO2 + 3 H2↑

(Sodium meta aluminate)

85. Which of this gas is liberated by the reaction of aluminium with acids?

a) Hydrogen

b) Oxygen

c) Nitrogen

d) Carbon dioxide

Explanation

Reaction with acids: With dilute and con.HCl it liberates H2 gas.

2 Al + 6 HCl → 2 AlCl3 + 3 H2↑

(Aluminium chloride)

Aluminium liberates hydrogen on reaction with dilute sulphuric acid and liberates sulphur dioxide on reaction with hot concentrated sulphuric acid.

86. Which of this acid reacts with aluminium and makes it as passive?

a) Hydrochloric acid

b) Nitric acid

c) Sulphuric acid

d) Carbonic acid

Explanation

Dilute or concentrated nitric acid does not attack aluminium but it renders aluminium passive due to the formation of an oxide film on its surface.

87. What is the result of the aluminothermic process?

a) Metal

b) Acid

c) Alkali

d) Oxygen

Explanation

As reducing agent: Aluminium is a powerful reducing agent. When a mixture of aluminium powder and iron oxide is ignited the latter is reduced to metal. This process is known as aluminothermic process. Fe2O3 + 2 Al → 2 Fe + Al2O3 + Heat.

88. Which is not a usage of Aluminium?

a) Electrical cables

b) Industrial machineries

c) Gold Jewelry

d) Household utensils

Explanation

Aluminium is used in household utensils, electrical cable industry, making aero planes and other industrial machine parts.

89. In which of this form copper is found naturally?

a) Native state only

b) Combined state only

c) Compounds only

d) Both a and b

Explanation

It was named as cuprum by the Romans because they got it from the Island of Cyprus. Copper is found in the native state as well as combined state.

90. Which of the following is not an ore of copper?

a) Cuprite

b) Ruby copper

c) Cu2O

d) CuSO4

Explanation

Ores of copper Formula

Copper pyrites CuFeS2

Cuprite or ruby copper Cu2O

Copper glance Cu2S

91. Which of this is the chief ore of copper?

a) Copper pyrite

b) Ruby copper

c) Copper glance

d) Cuprite

Explanation

The chief ore of copper is copper pyrite. It yields nearly 76% of the world production of copper.

92. How many steps are involved in the preparation of copper from its ore?

a) 4

b) 3

c) 5

d) 7

Explanation

Concentration of ore: The ore is crushed and the concentrated by froth floatation process and Roasting, Smelting, Bessemerisation and Refining

93. In which part impure copper metal is used in copper production technique?

a) Cathode

b) Anode

c) Electrolyte

d) All the above

Explanation

Cathode: A thin plate of pure copper metal.

Anode: A block of impure copper metal.

Electrolyte: Copper sulphate solution acidified with Sulphuric acid.

When electric current is passed through the electrolytic solution, pure copper gets deposited at the cathode and the impurities settle at the bottom of the anode in the form of sludge called anode mud.

94. Which of the following is not a quality of copper?

a) High melting point

b) High density

c) Low lustre

d) Brown metal

Explanation

Copper is a reddish brown metal with high lustre high density and high melting point (1356°C).

95. Which of these causes the copper to form its carbonates?

a) CO2

b) Sulphur

c) Impurities

d) Steam

Explanation

Chemical Properties of Copper

Action of Air and Moisture: Copper gets covered with a green layer of basic copper carbonate in the presence of CO2 and moisture.

2 Cu + O2 + CO2 + H2O → CuCO3.Cu(OH)2

96. Which of these are formed by reaction of heat and copper?

a) Oxide

b) Sulphide

c) Nitrite

d) Carbonate

Explanation

Action of Heat: On heating at different temperatures in the presence of oxygen, copper forms two types of oxides CuO and Cu2O.

2 Cu + O2 below 1370K 2 CuO (copper II oxide- black)

4 Cu + O2 above 1370K 2 Cu2O (copper I oxide – red)

97. Assertion (A): Copper dissolves in dilute HCl and H2SO4 in the presence of air.

Reasoning(R): Without air the dilute acids does not react with copper.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

With dilute HCl and dilute H2SO4: Dilute acids such as HCl and H2SO4 have no action on these metals in the absence of air. Copper dissolves in these acids in the presence of air.

2 Cu + 4 HCl + O2 (air) 2 CuCl2 + 2 H2O

98. Which of these following gas is liberated in the reaction of copper and HNO3?

a) Nitric oxide

b) Hydrogen Sulphide

c) Carbon monoxide

d) Helium

Explanation

With dil. HNO3: Copper reacts with dil. HNO3 with the liberation of Nitric Oxide gas.

3 Cu + 8 HNO3 → 3 Cu (NO3)2 + 2 NO ↑ + 4H2O

99. What is the end product of copper reacting with chlorine?

a) Copper nitrate

b) Copper Sulphide

c) Copper II chloride

d) Cupric acid

Explanation

Action of Chlorine: Chlorine reacts with copper resulting in the formation of copper (II) chloride. Cu + Cl2 CuCl2

100. Which of these does not affect the composition of copper?

a) Alkalis

b) Chlorine

c) Acids

d) Heat

Explanation

Action of Alkalis: Copper is not attacked by alkalis

101. What are the uses of copper?

a) Electroplating

b) Gold and silver jewels

c) Electric cables and appliances

d) All the above

Explanation

Uses of Copper: It is extensively used in manufacturing electric cables and other electric appliances. It is used for making utensils, containers, calorimeters and coins. It is used in electroplating. It is alloyed with gold and silver for making coins and jewels.

102. What are the natural forms of iron?

a) Oxides

b) Sulphides

c) Carbonates

d) All the above

Explanation

Iron is the second most abundant metal available next to aluminium. It occurs in nature as oxides, sulphides and carbonates.

103. Match

A. Iron pyrite i) Fe2O3

B. Haematite ii) Fe3O4

C. Magnetite iii) FeS2

a) iii, i, ii

b) i, iii, ii

c) ii, iii, i

d) ii, i, iii

Explanation

The ores of iron are as follows: Ores of iron Formula

Haematite Fe2O3

Magnetite Fe3O4

Iron pyrite FeS2

104. Which of these ore is the chief source of iron?

a) Haematite

b) Magnetite

c) Iron Pyrite

d) All the above

Explanation

Iron is chiefly extracted from haematite ore (Fe2O3)

105. Which of these is used in gravity separation to clean powdered ore?

a) Water steam

b) Low pressure air

c) High pressure air

d) Cold water

Explanation

Concentration by Gravity Separation: The powdered ore is washed with a steam of water. As a result, the lighter sand particles and other impurities are washed away and the heavier ore particles settle down.

106. Which of these iron impurities are oxidized in the roasting and calcination method?

a) Sulphur

b) Arsenic

c) Phosphorus

d) All the above

Explanation

Roasting and Calcination: The concentrated ore is strongly heated in a limited supply of air in a reverberator furnace. As a result, moisture is driven out and sulphur, arsenic and phosphorus impurities are oxidized off.

107. Which of the region is known as the fusion zone?

a) Middle region

b) Upper region

c) Lower region

d) All the above

Explanation

The Middle Region (Fusion Zone) – The temperature prevails at 1000°C. In this region, CO2 is reduced to CO. CO2 + C 2 CO – Heat

Limestone decomposes to calcium oxide and CO2. CaCO3 CaO + CO2 – Heat

These two reactions are endothermic due to absorption of heat. Calcium oxide combines with silica to form calcium silicate slag. CaO + SiO2 CaSiO3

108. Which of this iron is formed in the reduction zone?

a) Spongy iron

b) Pig iron

c) Cast iron

d) All the above

Explanation

The Upper Region (Reduction Zone)- The temperature prevails at 400°C . In this region carbon monoxide reduces ferric oxide to form a fairly pure spongy iron.

Fe2O3 + 3CO 400°C 2Fe + 3CO2 ↑

The molten iron is collected at the bottom of the furnace after removing the slag. The iron thus formed is called pig iron. It is remelted and cast into different moulds. This iron is called cast iron.

109. Which of these physical properties of iron is not true?

a) A lustrous metal.

b) Low tensility and ductility.

c) Can be magnetized.

d) Greyish white color.

Explanation

Physical properties of Iron: It is a lustrous metal, greyish white in color. It has high tensility, malleability and ductility. It can be magnetized.

110. Which of these results in heating iron with air or oxygen?

a) Hydrated ferric sulphate

b) Ferric Sulphide

c) Ferrous oxide

d) Carbon monoxide

Explanation

Reaction with air or oxygen: Only on heating in air iron forms magnetic oxide.

3 Fe + 2 O2 Fe3O4 (black)

111. Assertion (A): The Brown hydrated ferric oxide forming on the surface of iron is called as rust.

Reasoning(R): Exposing iron to moist air forms rust and the phenomenon is known as rusting.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Reaction with moist air: When iron is exposed to moist air, it forms a layer of brown hydrated ferric oxide on its surface. This compound is known as rust and the phenomenon of formation of rust is known as rusting.

4 Fe+ 3 O2 + x H2O 2 Fe2O3 . x H2O(rust)

112. Which of these results in magnetic oxide with iron?

a) Cool water

b) Hydrogen gas

c) Steam

d) High pressure water

Explanation

Reaction with steam: When steam is passed over red hot iron, magnetic oxide is formed.

3 Fe + 4 H2O (steam) Fe3O4 + 4 H2 ↑

113. What is the result of the chemical reaction of iron and chlorine?

a) Ferric Chloride

b) Ferrous oxides

c) Ferrous nitrates

d) None of the above

Explanation

Reaction with chlorine: Iron combines with chlorine to form ferric chloride.

2Fe + 3Cl2 2FeCl3 (ferric chloride)

114. Which of this gas is liberated in the chemical reaction of Iron and acids?

a) Carbon dioxide

b) Hydrogen

c) Nitrogen

d) Helium

Explanation

Reaction with acids: With dilute HCl and dilute H2SO4 it liberates H2 gas.

Fe + 2HCl FeCl2 + H2 ↑

Fe + H2SO4 FeSO4 + H2 ↑

115. Which acid reacts with iron results in its nitrates?

a) HNO3

b) H2SO4

c) HCl

d) H2S

Explanation

With dilute HNO3 in cold condition iron gives ferrous nitrate and ammonium nitrate.

116. Which of these is not a usage of pig iron?

a) Pipes

b) Railings

c) Television towers

d) Drain pipes

Explanation

Pig iron (Iron with 2.0% – 4.5% of carbon): It is used in making pipes, stoves, radiators, railings, manhole covers and drain pipes.

117. Assertion (A): Steel is used in the constructions, machineries and for transmission cables.

Reasoning (R): Iron with 0.25%- 2.0% of carbon is used for steel.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Steel (Iron with 0.25% – 2.0% of carbon): It is used in the construction of buildings, machinery, transmission cables and T.V towers and in making alloys.

118. What percentage of carbon makes a wrought iron?

a) < 0.50%

b) =0.25%

c) >0.15%

d) <0.25%

Explanation

Wrought iron (Iron with < 0.25% of carbon): It is used in making springs, anchors and electromagnets.

119. Assertion (A): Alloy is a heterogeneous mixture of two or more metals.

Reasoning (R): The alkali elements of metals are used to form an alloy.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

An alloy is a homogeneous mixture of two or more metals or of one or more metals with certain non-metallic elements.

120. Which of this metal is used to increase the strength and utility of gold?

a) Copper

b) Zinc

c) Silver

d) Brass

Explanation

The properties of alloys are often different from those of its components. Pure gold is brittle to be used. The addition of small percentage of copper enhances its strength and utility.

121. Which of these is used with metals in an amalgam?

a) Gold

b) Iron

c) Copper

d) Mercury

Explanation

An amalgam is an alloy of mercury with another metal. These alloys are formed through metallic bonding with the electrostatic force of attraction between the electrons and the positively charged metal ions. Silver tin amalgam is used for dental filling.

122. Which of these metals are used to make brass?

a) Zinc, Copper

b) Iron, Tin

c) Copper, Gold

d) Silver, Zinc

Explanation

Method of making alloys : By fusing the metals together. E.g. Brass is made by melting zinc and copper.

123. Which of these metals does not included in making wood metal?

a) Lead

b) Bismuth

c) Copper

d) Cadmium powder

Explanation

Method of making alloys: By compressing finely divided metals. E.g. Wood metal: an alloy of lead, tin, bismuth and cadmium powder is a fusible alloy.

124. Which of these is used as solvent in solid alloy solutions?

a) High concentration metals

b) High density metals

c) Low concentration metals

d) Low density metals

Explanation

Alloys as solid solutions: Alloys can be considered as solid solutions in which the metal with high concentration is solvent and other metals are solute. For example, brass is a solid solution of zinc (solute) in copper (solvent).

125. Choose the correct statements.

i) Iron alloys can be classified into ferrous and Non-ferrous alloys.

ii) Ferrous alloys contain iron as major component.

iii) Aluminum alloy is an example of Non-ferrous alloys.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Based on the presence of Iron alloys can be classified into

Ferrous alloys: Contain Iron as a major component. A few examples of ferrous alloys are Stainless Steel, Nickel Steel etc.

Non-ferrous alloys: These alloys do not contain Iron as a major component. For example, Aluminium alloy, Copper alloy etc.

126. What type of alloy is Brass?

a) Copper Alloy

b) Ferrous Alloy

c) Aluminium Alloy

d) Iron Alloy

Explanation

127. Which of these alloys are used in aircrafts and scientific instruments?

a) Magnalium

b) Bronze

c) Tin

d) Nickel steel

Explanation

Aluminium Alloys (Non- ferrous)

128. Which of these constitute the nickel steel?

a) Iron

b) Carbon

c) Nickel

d) All the above

Explanation

Iron Alloys (Ferrous)

129. Which of these is not the reason for alloying?

a) Modify appearance and color.

b) Lower melting point.

c) Increase hardness and tensile strength.

d) Decreases resistance to electricity.

Explanation

Reasons for alloying: To modify appearance and color, To modify chemical activity, To lower the melting point, To increase hardness and tensile strength, To increase resistance to electricity.

130. Assertion (A): Alloying is destruction of materials by electrochemical and chemical reaction with environment.

Reasoning(R): The natural process of alloying converts metals into its oxides, hydroxide or Sulphide.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Alloying is the gradual destruction of metals by chemical or electrochemical reaction with the environment. It is a natural process which converts a metal into its oxide, hydroxide or Sulphide so that it loses its metallic characteristics.

131. Which of these are chemically known as rust?

a) Hydrated Ferric oxide

b) Ferrous oxide

c) Fe2O3.H2O

d) Both a and c

Explanation

Rust is chemically known as hydrated ferric oxide (it is formulated as Fe2O3 .xH2O).Rusting results in the formation of scaling reddish brown hydrated ferric oxide on the surface of iron and iron containing materials.

132. Which of these does not cause dry corrosion?

a) O₂

b) H₂O

c) H₂S

d) N₂

Explanation

Dry Corrosion or Chemical Corrosion: The corrosive action in the absence of moisture is called dry corrosion. It is the process of a chemical attack on a metal by a corrosive liquids or gases such as O2, N2, SO2, H2S etc. It occurs at high temperature. Of all the gases mentioned above O2 is the most reactive gas to impart the chemical attack.

133. Assertion (A): Wet corrosion occurs due to the presence of moisture in metals.

Reasoning (R): The electrochemical reaction of metal with water or aqueous solution of salt, acids and bases.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Wet Corrosion or Electrochemical Corrosion: The corrosive action in the presence of moisture is called wet corrosion. It occurs as a result of electrochemical reaction of metal with water or aqueous solution of salt or acids or bases.

134. Which of this metal uses alloying method to prevent from corrosion?

a) Stainless steel

b) Iron

c) Copper

d) Sodium

Explanation

Methods of preventing corrosion

Alloying: The metals can be alloyed to prevent from the process of corrosion. E.g: Stainless Steel

135. Which is not a surface coating method for protecting metals?

a) Galvanization

b) Alloying

c) Anodizing

d) Electroplating

Explanation

Surface Coating: It involves application of a protective coating over the metal. It is of the following types: Galvanization, Electroplating, and Anodizing and Cathodic protection.

136. Which of these is used in galvanization method?

a) Zinc on iron sheets

b) Tin on iron rods

c) Copper on Gold

d) Electro chemical coating

Explanation

Galvanization: It is the process of coating zinc on iron sheets by using electric current.

137. Which of this process uses electric current to coat a metal?

a) Alloying

b) Anodizing

c) Cathodic protection

d) Electroplating

Explanation

Electroplating: It is a method of coating one metal over another metal by passing electric current.

138. Which of this metal is used for anodizing process?

a) Zinc

b) Tin

c) Aluminium

d) Copper

Explanation

Anodizing: It is an electrochemical process that converts the metal surface into a decorative, durable and corrosion resistant. Aluminium is widely used for anodizing process.

139. What metal is used for cathodic protection?

a) Sacrificial metal

b) Non-metals

c) Alloys

d) Alkalis

Explanation

Cathodic Protection: It is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible. The easily corrodible metal is called sacrificial metal to act as anode ensuring cathodic protection.

140. When Pamban Bridge was opened in India?

a) 1930

b) 1945

c) 1914

d) 1887

Explanation

Pamban is a railway bridge which connects the town of Rameshwaram on Pamban Island to mainland India. Opened on 1914, it was India’s first sea bridge in India until the opening of the Bandra Worli Sea Link in 2010.

10th Science Lesson 9 Questions in English

9] Solutions

1. Assertion (A): Smoke released from wood burning is a mixture of carbon and gases like CO2 and CO.

Reasoning (R): A mixture may exist in one or more than one physical state.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

The substances present in a mixture may exist in one or more physical state. For example, when we burn wood, the smoke released is a mixture of solid carbon and gases like CO2, CO, etc.

2. What type of mixtures is called as solutions?

a) Non-dilute

b) Heterogeneous

c) Compound

d) Homogenous

Explanation

The kind of homogenous mixtures are termed as “solutions”.

3. What is the important characteristic of a solute?

a) Lesser weighing component

b) Easily Dilatable

c) Compounds

d) More than one physical state

Explanation

A solution is a homogeneous mixture of two or more substances. In a solution the component which is present in lesser amount (by weight), is called solute and the component, which is present in a larger amount (by weight) is called solvent.

4. Which of the following acts as a dissolving medium in a solution?

a) Solute

b) Heterogeneous compounds

c) Solvent

d) Salts

Explanation

The solute gets distributed uniformly throughout the solvent and thus forming the mixture homogeneous. So, the solvent acts as a dissolving medium in a solution.

5. Define dissolution.

a) Complete dissolvent in solutions.

b) Uniform distribution of solute into solvent.

c) Partial solute into solvent.

d) Dissolving process of solute.

Explanation

The process of uniform distribution of solute into solvent is called dissolution.

6. What is the name of solutions containing two components?

a) Binary solutions

b) Mono solutions

c) Dual solutions

d) All the above

Explanation

A solution must at least be consisting of two components (a solute and a solvent). Such solutions which are made of one solute and one solvent (two components) are called binary solutions.

7. How many solvents are present in ternary solutions?

a) One

b) Three

c) Two

d) More than two

Explanation

A solution may contain more than two components. For example if salt and sugar are added to water, both dissolve in water forming a solution. Here two solutes are dissolved in one solvent. Such kinds of solutions which contain three components are called ternary solutions.

8. Which of these determine the characteristics of the binary solution?

a) Solute

b) Physical state

c) Solvent

d) Dissolution

Explanation

In binary solutions, both the solvent and solute may exist in any of these physical states. But the solvent constitutes the major part of the solution. Its physical state is the primary factor which determines the characteristics of the solution.

9. Match

A. Gaseous solutions i) Mercury with Sodium

B. Liquid solutions ii) Water vapor in air

C. Solid solutions iii) Sodium chloride in water

a) ii, iii, i

b) i, iii, ii

c) ii, i, iii

d) iii, ii, i

10. What is the state of solvent in Copper dissolved in gold?

a) Solid

b) Liquid

c) Gas

d) All the above

Explanation

Types of Binary Solutions

11. Which is called as the Universal solvent?

a) Water

b) Air

c) Carbon dioxide

d) Water vapor

Explanation

Most of the substances are soluble in water. That is why, water is called as ‘Universal solvent”.

12. How many types of solutions are classified based on solvent?

a) 3

b) 5

c) 2

d) 4

Explanation

On the basis of type of solvent solutions are classified into two types. They are aqueous solutions and non-aqueous solutions.

13. Which of the following is not an aqueous solution?

a) Copper sulphate in water

b) Water vapor in air

c) Common salt in water

d) Sugar in water

Explanation

The solution in which water acts as a solvent is called aqueous solution. E.g. Common salt in water, Sugar in water and Copper sulphate in water.

14. Assertion (A): Non-aqueous solution has liquids other than water as solvent.

Reasoning (R): Solvent other than water is referred as non-aqueous solvent.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

The solution in which any liquid other than water acts as a solvent is called non-aqueous solution. Solvent other than water is referred to as non-aqueous solvent.

15. What are the non-aqueous solvents?

a) Ethers

b) Acetone

c) Benzene

d) All the above

Explanation

Generally alcohols, benzene, ethers, carbon disulphide, acetone, etc., are used as non-aqueous solvents.

16. Which of these is an example for non-aqueous solutions?

a) Ethyl alcohol in water

b) Iodine dissolved in carbon tetrachloride

c) Soda water

d) Sodium chloride dissolved in water

Explanation

Examples for non-aqueous solutions: Sulphur dissolved in carbon disulphide, Iodine dissolved in carbon tetrachloride.

17. How many types of solutions are classified based on the amount of solvent?

a) 5

b) 2

c) 4

d) 3

Explanation

Based on the amount of solute in the given amount of solvent, solutions are classified into the following types as, saturated solution, unsaturated solution and Super saturated solution.

18. What are the characteristics and conditions for a saturated solution?

a) No more solute

b) Definite amount of solvent

c) Temperature

d) All the above

Explanation

Saturated solution: A solution in which no more solute can be dissolved in a definite amount of the solvent at a given temperature is called saturated solution. e.g. 36 g of sodium chloride in 100 g of water at 25°C forms saturated solution.

19. Which of the following statement is correct for an unsaturated solution?

a) Less solvent and solute in room temperature.

b) Less solute than the super saturated solution.

c) Less solute than the saturated solution at given temperature.

d) Less solute and major solvent in ideal temperature.

Explanation

Unsaturated solution: Unsaturated solution is one that contains less solute than that of the saturated solution at a given temperature. e.g. 10 g or 20 g or 30 g of Sodium chloride in 100 g of water at 25°C forms an unsaturated solution.

20. Name the solution which has more solute than the saturated solution?

a) Dissolution

b) Non-aqueous solution

c) Unsaturated solution

d) Super saturated solution

Explanation

Super saturated solution is one that contains more solute than the saturated solution at a given temperature. e.g. 40 g of sodium chloride in 100 g of water at 25°C forms super saturated solution.

21. Choose the Incorrect statements regarding the super saturated solution.

i) Temperature and pressure conditions are altered.

ii) Super saturated solutions are stable.

iii) The solute reappears as crystals if the solution is disturbed.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Super saturated solution state can be achieved by altering any other conditions liken temperature, pressure. Super saturated solutions are unstable, and the solute is reappearing as crystals when the solution is disturbed.

22. Which of the following is the classification of unsaturated solutions?

a) Ternary, Binary solutions

b) Concentrated, Dilute solutions

c) Compounds, Mixture solutions

d) Percentage, Volume solutions

Explanation

Concentrated and dilute solutions: It is another kind of classification of unsaturated solutions. It expresses the relative concentration of two solutions with respect to their solutes present in the given amount of the solvent.

23. Which of the solution has higher amount of solute per given solvent?

a) Concentrated solution

b) Dilute solutions

c) Saturated solutions

d) Super saturated solutions

Explanation

When we compare two solutions having same solute and solvent the one which contains higher amount of solute per the given amount of solvent is said to be ‘concentrated solution’.

24. Assertion (A): Dilute and concentration solution does not decide the quality of the solute.

Reasoning (R): Dilute solution or concentration solution is the quantitative representation.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Differentiating solutions as dilute and concentrated is a qualitative representation. It does not imply the quantity of the solute. This difference is observed by means of some physical characteristics such as color, density, etc.

25. Which of these factors is measured by the solubility?

a) Extent of dissolution

b) Quality of solution

c) Quantity of solvent

d) Physical characteristics of solution

Explanation

The extent of dissolution of a solute in a solvent can be better explained by its solubility. Solubility is a measure of how much of a solute can be dissolved in a specified amount of a solvent.

26. Choose the correct statements.

i) Solubility is defined as the number of grams of a solute dissolved in 100g of a solvent.

ii) Solubility is measured at a given temperature and pressure.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Solubility is defined as the number of grams of a solute that can be dissolved in 100 g of a solvent to form its saturated solution at a given temperature and pressure.

27. What is the mathematical expression for solubility?

a) (Mass of the solute / Mass of the solvent) * 100

b) Mass of the solvent / Mass of the concentration

c) Total concentration of solvent / Total mass of the solution

d) (Mass of the concentration / Mass of solvent) * 100

Explanation

The solubility is mathematically expressed as,

28. Match

A. Sodium hydroxide i) 91

B. Ammonia ii) 48

C. Calcium carbonate iii) 80

D. Glucose iv) 0.0013

a) iv, i, iii, ii

b) ii, i, iii, iv

c) iii, ii, iv, i

d) i, iii, ii, iv

29. What is the solubility of sodium iodide in water at 25°C?

a) 184

b) 36

c) 95

d) 89

Explanation

Solubility’s of some common substances in water at 25°C

30. What are the governing factors for solubility of a solute?

a) Temperature

b) Nature of solvent

c) Pressure

d) All the above

Explanation

There are three main factors which govern the solubility of a solute. They are Nature of the solute and solvent, Temperature and Pressure.

31. Choose the correct statements.

i) Water dissolves all substances.

ii) The nature of solvent is an important factor in solubility.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Nature of the solute and solvent: The nature of the solute and solvent plays an important role in solubility. Although water dissolves an enormous variety of substances both ionic and covalent, it does not dissolve everything.

32. Assertion (A): Non-polar compounds are soluble in non-polar solvents.

Reasoning (R): Polar compounds do not dissolve in non-polar solvents.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Non-polar compounds are soluble in non-polar solvents. For example, Fat dissolved in ether. But non-polar compounds do not dissolve in polar solvents; polar compounds do not dissolve in non-polar solvents.

33. Which of these increase the solubility of solute in liquid solvents?

a) Temperature rise

b) Mass of solvent

c) Concentration of solute

d) All the above

Explanation

Generally solubility of a solid solute in a liquid solvent increases with increase in temperature. For example, a greater amount of sugar will dissolve in warm water than in cold water.

34. In which of these process solubility decrease with increase in temperature?

a) Endothermic

b) Equilibrium

c) Exothermic

d) Ideal process

Explanation

The solubility of the endothermic process increases with increase in temperature. Exothermic process solubility decreases with increase in temperature.

35. What is the effect of temperature rise in liquids?

a) Increase of concentration of solvent

b) Decrease in solubility of gas

c) Increase in pressure

d) Decrease of solvents

Explanation

The Solubility of gases in liquid decrease with increase in temperature. Generally, water contains dissolved oxygen. If water is heated the solubility of oxygen in water decreases so oxygen escapes in the form of bubbles.

36. Assertion (A): Aquatic animals use the dissolved oxygen in cold water.

Reasoning (R): Oxygen has high solubility at low temperatures.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

Aquatic animals live more in cold regions because more amount of dissolved oxygen is present in the water of cold regions. This shows that the solubility of oxygen in water is more at low temperatures.

37. Which of these factor increases the solubility of a gas in liquid?

a) Mass of solute

b) Surface tension

c) Pressure

d) Concentration of solution

Explanation

Effect of pressure is observed only in the case of solubility of a gas in a liquid. If the pressure is increased the solubility of a gas in liquid increases.

38. What are the examples for gas solubility in liquids?

a) Carbonated beverages

b) Household cleaners

c) Formalin aqueous solution

d) All the above

Explanation

The common examples for solubility of gases in liquids are carbonated beverages, i.e. Soft drinks, household cleaners containing aqueous solution of ammonia, formalin aqueous solution of formaldehyde, etc.

39. Define the Henry’s law of solubility of gas in liquid.

a) Solubility of gas is directly proportional to the pressure of gas at definite temperature.

b) Solubility of liquid is directly proportional to the temperature of solvent.

c) Solubility of gas is equal to the solubility of liquid.

d) Solubility of gas and liquid are inversely proportional.

Explanation

The effect of pressure on the solubility of a gas in liquid is given by Henry’s law. It states that, the solubility of a gas in a liquid is directly proportional to the pressure of the gas over the solution at a definite temperature.

40. Which is used to quantify the solute in a solution?

a) Temperature

b) Solubility

c) Concentration

d) All the above

Explanation

Most of the chemical reactions take place in solutions form. So it is essential to quantify the solute in solvent to study the reactions. To quantify the solute in a solution, we can use the term “concentration”.

41. Define concentration of a solution.

a) Amount of solute in given amount of solution or solvent.

b) Mass of the solvent in a solution.

c) Ratio of mass of solvent and solution.

d) Amount of solute in a solution.

Explanation

Concentration of a solution may be defined as the amount of solute present in a given amount of solution or solvent.

42. Which of these is used to represent the quantity of the concentration of a solution?

a) % Pressure

b) % Mass

c) % Kilogram

d) % Quality

Explanation

Quantitatively, concentration of a solution may be expressed in different methods. But here we shall discuss percentage by mass (% mass) and percentage by volume (% volume).

43. What percentage value is used to describe the liquid solvent and solutes?

a) Surface tension

b) Mass

c) Pressure

d) Temperature

Explanation

Mass percentage of a solution is defined as the percentage by mass of the solute present in the solution. It is mostly used when solute is solid and solvent is liquid.

Mass Percentage = (Mass of the solute / Mass of the solution) * 100

44. Which of this property is independent of mass percentage?

a) Temperature

b) Pressure

c) Solvent

d) Liquidity

Explanation

Usually, mass percentage is expressed as w/w (weight / weight); mass percentage is independent of temperature.

45. Calculate the volume percentage of a solution made from 35 ml of ethanol and 65 ml of water.

a) 70%

b) 35%

c) 100%

d) 30%

Explanation

Volume of the ethanol = 30 ml and Volume of the water = 70 ml

Volume percentage = (Volume of the solute / Volume of the solution)* 100

= Volume of the solute / (Volume of the solute + Volume of the solvent) * 100

Volume percentage = 30 / (30+ 70) * 100 = 30%

46. Find the mass percentage of solute and solvent for 16 grams of NaOH dissolved in 100 grams of water at 25°C to form a saturated solution.

a) 16.67%, 83.33%

b) 83.33%, 23.45%

c) 16.67%, 87.33%

d) 12.67%, 88.21%

Explanation

Mass of the solute (NaOH) = 20 g and Mass of the solvent H2O = 100 g

Mass percentage of the solute = Mass percentage of solute / (Mass of the solute +Mass of the

Solvent)*100

= 20 * 100 / (20+100) = 16.67 %

Mass percentage of solvent = 100 – (Mass percentage of the solute) = 100- 16.67 = 83.33%

47. Which of this factor is decreased in liquids with increase in temperature?

a) Volume percentage

b) Pressure percentage

c) Concentration percentage

d) Mass percentage

Explanation

Usually volume percentage is expressed as v/v (volume / volume). It is used when both the solute and solvent are liquids. Volume percentage decreases with increases in temperature, because of expansion of liquid.

48. Which of these commercial products concentration is expressed as w/w?

a) Ointments

b) Soaps

c) Antacid

d) All the above

Explanation

In the commercial products that we come across in our daily life such as a solution of syrups, mouth wash, antiseptic solution, household disinfectants etc., the concentration of the ingredients is expressed as v/v. Similarly, in ointments, antacid, soaps etc., the concentration of solutions are expressed as w/w.

49. Which of this solution is involved in hydration process?

a) Unsaturated solution

b) Saturated aqueous solution

c) Super saturated gaseous solution

d) Saturated gaseous solution

Explanation

When ionic substances are dissolved in water to make their saturated aqueous solution, their ions attract water molecules which then attached chemically in certain ratio. This process is called hydration.

50. Choose the correct statements.

i) Hydrated salts have indefinite number of water molecules.

ii) The number of water molecules in the crystalline substance is called as the water of crystallization.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

The ionic substances crystallize out from their saturated aqueous solution with a definite number of molecules of water. The number of water molecules found in the crystalline substance is called water of crystallization. Such salts are called hydrated salts.

51. Assertion (A): Hydrated crystalline salts lose their water of crystallization on heating.

Reasoning (R): On heating the hydrated crystalline salts it become amorphous and loses its color.

a) Both A and R is True and R is the correct explanation of A.

b) Both A and R is True but R is not the correct explanation of A.

c) A is True but R is False.

d) Both A and R is False.

Explanation

On heating these hydrated crystalline salts they lose their water of crystallization and become amorphous or lose their color (if they are colored).

52. Identify the Incorrect match.

A. Green vitriol i) Iron sulphate hepta hydrate

B. Gypsum ii) Calcium sulphate dihydrate

C. White vitriol iii) Magnesium sulphate hepta hydrate

D. Blue vitriol iv) Copper sulphate pentahydrate

a) i only

b) ii only

c) iii only

d) iv only

Explanation

Hydrated salts

53. What is the number of water molecules in blue vitriol?

a) 5

b) 7

c) 9

d) 11

Explanation

The number of water molecules in blue vitriol is five. So its water of crystallization is 5. When blue colored copper sulphate crystals are gently heated, it loses its five water molecules and becomes colorless anhydrous copper sulphate.

54. Which of these has seven water molecules?

a) Epsom salt

b) Blue vitriol

c) Copper Chloride

d) Sodium Hydroxide

Explanation

Magnesium sulphate hepta-hydrate MgSO4.7H2O (Epsom salt) water of crystallization is 7. When magnesium sulphate hepta-hydrate crystals are gently heated, it loses seven water molecules and becomes anhydrous magnesium sulphate.

55. What are the conditions for the hygroscopic substances?

a) Ordinary temperature

b) No change in physical state

c) Absorbs air moisture

d) All the above

Explanation

Certain substances when exposed to the atmospheric air at ordinary temperature absorb moisture without changing their physical state. Such substances are called hygroscopic substances and this property is called hygroscopy.

56. Which of these is not a hydroscopic agent?

a) H₂SO₄

b) P₂O₅

c) HCl

d) SiO₂

Explanation

Hygroscopic substances are used as drying agents. Example: Con Sulphuric acid (H2SO4), Phosphorus Pentoxide (P2O5), Quick lime (CaO) and Silica gel (SiO2).

57. Which of this solution is obtained by the dissolved deliquescent substances?

a) Unsaturated solution

b) Heterogeneous solution

c) Saturated solution

d) Concentrated solution

Explanation

Deliquescent substances lose their crystalline shape and ultimately dissolve in the absorbed water forming a saturated solution.

58. In which of this condition deliquescence property has maximum value?

a) Low temperature

b) Low pressure

c) Humid atmosphere

d) Both a and c

Explanation

Deliquescence is at its maximum when the temperature is low and the atmosphere is humid.

59. Which of these are the examples of deliquescence?

a) Caustic potash

b) Caustic soda

c) Ferric chloride

d) All the above

Explanation

Examples for deliquescence are Caustic soda (NaOH), Caustic potash (KOH) and Ferric chloride (FeCl3).

60. Choose the Incorrect statements.

i) The hygroscopic substances do not change its physical state on air exposure.

ii) Deliquescent substances absorb moisture and dissolve if exposed to atmospheric air.

iii) Hygroscopic substances are crystalline solids.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

10th Science Lesson 10 Questions in English

10] Types Of Chemical Reactions

1. Which of the following are involved in chemical reaction?

1. Breaking of old chemical bonds
2. Formation of a substance which has a property other than that of reactants
3. Formation of new chemical bonds
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

A chemical reaction involves breaking of old chemical bonds and formation of new chemical bonds. This change may happen spontaneously or it may be facilitated by external forces or energy. A chemical reaction does not involve in formation of a substance which has a property other than that of reactants.

2. Match the following:

1. Human getting energy 1. Combustion of a fuel
2. Plants growing 2. Digestion of food
3. Moving car 3. Oxidation of iron
4. Rusting 4. Absorbing nutrients from soil
5. 3, 1, 2, 4
6. 2, 4, 1, 3
7. 2, 4, 3, 1
8. 2, 1, 3, 4

Explanation

Human gets energy from the digestion of the food you eat. Plants grow by absorbing nutrients from the Earth and get their food by photosynthesis. The combustion of a fuel makes the car to move. Oxidation of iron causes rusting.

3. Which of the following are the resultants of burning of petrol?

1. Water
2. Carbon Monoxide
3. Carbon Di-oxide
4. 1, 3
5. 1, 2
6. 2, 3
7. All the above

Explanation

In chemical reaction process chemical changes i.e. the materials, which undergo changes are converted into some other new materials. For example, by burning petrol, the hydrocarbons present in it are converted into carbon dioxide and water.

4. Which of the following happens during a chemical reaction?

1. In a chemical reaction, the atoms of the reacting molecules or elements are rearranged to form new molecules.
2. Old chemical bonds between atoms are broken and new chemical bonds are formed
3. Bond breaking absorbs energy whereas bond formation releases energy
4. All the above

Explanation

In a chemical reaction following changes happen:

• In a chemical reaction, the atoms of the reacting molecules or elements are rearranged to form new molecules.
• Old chemical bonds between atoms are broken and new chemical bonds are formed.
• Bond breaking absorbs energy whereas bond formation releases energy

5. In a chemical reaction compounds which undergo reactions are called as_______

1. Products
2. Reactants
3. Catalyst
4. None

Explanation

In the chemical equation, the chemicals of the reaction are represented by their chemical formulas. Compounds or elements, which undergo reactions (reactants) are shown to the left of an arrow and the compounds formed (products) are shown to the right of the arrow. The arrow indicates the direction of the reaction.

6. A + B 🡪 C + D

1. A 1. Oxygen
2. B 2. Methane
3. C 3. Water
4. D 4. CO2

Match the following correctly:

1. 3, 1, 2, 4
2. 2, 1, 4, 3
3. 4, 1, 2, 3
4. 4, 3, 2, 1

Explanation

When methane reacts with oxygen, it forms carbon dioxide and water. How can you represent this reaction? It can be written as a word equation as shown below:

Methane + Oxygen → Carbon dioxide + Water

7. CH4 + O2 → CO2 + H2 O

Assertion(A): This is an incomplete chemical equation

Reason(R): The law of conservation of matter states that matter cannot be created or destroyed.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

CH4 + O2 → CO2 + H2 O

This is also an incomplete chemical equation. Because, the law of conservation of matter states that matter cannot be created or destroyed. You cannot create new atoms by a chemical reaction. In contrast, they are rearranged in different ways by a chemical reaction to form a new compound. So, in a chemical equation, the number of atoms of the reactants and that of the products must be equal.

8. Which of the following is the correct balanced chemical reaction?

1. CH4 + 2O2 → CO2 + 2H2 O
2. CH4 + 2O2 → CO2 + H2 O
3. CH4 + O2 → CO2 + 2H2 O
4. 2CH4 + 2O2 → CO2 + 2H2 O

Explanation

On balancing the number of atoms, the following equation can be obtained:

CH4 + 2O2 → CO2 + 2H2 O

A balanced chemical equation is the simplified representation of a chemical reaction which describes the chemical composition, physical state of the reactants and the products, and the reaction conditions.

9. The physical state of the substances in a chemical reaction are denoted in short form within a

bracket, as the _____ of the formula

1. Super subscript
2. Subscript
3. Mega subscript
4. None

Explanation

The phases or the physical state of the substances in a chemical reaction are denoted in short form within a bracket, as the subscript of the formula, of the respective substances.

10. Match the following substances with their state when potassium reacts with water?

1. Potassium 1. Liquid
2. Water 2. Gas
3. Hydrogen 3. Aqueous solution
4. Potassium hydroxide 4. Solid
5. 2, 1, 4, 3
6. 4, 1, 2, 3
7. 1, 3, 2, 4
8. 4, 2, 1, 3

Explanation

When solid potassium reacts with liquid water, it produces hydrogen gas and potassium hydroxide solution. All the information of the reaction is given in the chemical equation as shown below:

2K(s) + 2H2 O(I) → 2KOH (aq) + H2(g)

11. ___________ is a reaction in which two or more reactants combine to form a compound

1. Combination reaction
2. De-combination reaction
3. Redox reaction
4. None

Explanation

A combination reaction is a reaction in which two or more reactants combine to form a compound. It is otherwise called ‘synthesis reaction’ or ‘composition reaction’.

12. Hydrogen gas combines with chlorine gas to form______

1. Hydrogen chloride gas
2. HCl acid
3. Aqueous solution of HCl
4. None

Explanation

Hydrogen gas combines with chlorine gas to form hydrogen chloride gas.

H2(g) + Cl2(g) → 2HCl(g)

13. Depending on chemical nature of the reactant, combination reaction is classified into___ types

1. 3
2. 2
3. 5
4. 4

Explanation

Depending on the chemical nature of the reactants, there are three classes of combination reactions:

• Element + Element → Compound
• Compound + Element → Compound
• Compound + Compound → Compound

14. When Solid sulphur reacts with oxygen forms_____

1. Sulphur dioxide
2. Sulphur oxide
3. Sulphuric oxide
4. Hydrogen Sulphide

Explanation

When solid sulphur reacts with oxygen, it produces sulphur dioxide. Here both the reactants are non-metals.

S(s) + O2(g) → SO2(g)

15. What is the colour of Sodium and Chlorine gas?

1. White, green
2. White, Pale yellow green
3. Pale yellow, white
4. White, White

Explanation

Sodium, a silvery-white metal, combines with chlorine, a pale-yellow green gas, to form sodium chloride, an edible compound. Here one of the reactants is a metal (sodium) and the other (chlorine) is a nonmetal.

2Na(s) + Cl2(g) → 2NaCl(s)

16. Which of the following is a Compound + Element reaction?

1. H2 + Cl2 → 2HCl
2. PCl3 + Cl2 → PCl5
3. SiO2 + CaO → CaSiO3
4. None

Explanation

A compound reacts with an element to form a new compound. For instance, phosphorous trichloride reacts with chlorine gas and forms phosphorous pentachloride.

PCl3(I) + Cl2(g) → PCl5(s)

17. Most of the combination reactions are_____ in nature

1. Exothermic
2. Endothermic
3. Redox
4. None

Explanation

In the following reaction, silicon dioxide reacts with calcium oxide to form calcium silicate.

SiO2(s) + CaO(s) → CaSiO3(s)

Most of the combination reactions are exothermic in nature. Because, they involve the formation of new bonds, which releases a huge amount of energy in the form of heat.

18. Which of the following statement about decomposition reaction is/are incorrect?

1. In a decomposition reaction, a single compound splits into two or more simpler substances under suitable conditions
2. It is the opposite of the combination reaction
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

In a decomposition reaction, a single compound splits into two or more simpler substances under suitable conditions. It is the opposite of the combination reaction. Th e generalised scheme of a decomposition reaction is given below:

19. Depending on the nature of energy used in decomposition reaction it is classified into____ types

1. 2
2. 5
3. 3
4. 4

Explanation

Breaking of bonds is the major phenomenon in a decomposition reaction and hence it requires energy to break the bonds, depending on the nature of the energy used in the decomposition reaction. There are three main classes of decomposition reactions. They are

• Thermal Decomposition Reactions
• Electrolytic Decomposition Reactions
• Photo Decomposition Reactions

20. Which of the following is used in white washing walls?

1. Calcium oxide
2. Calcium carbonate
3. Slaked lime
4. None

Explanation

A solution of slaked lime is used for white washing walls. Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls.

21. What is the chemical formula of marble?

1. CaCO3
2. CaO
3. Ca (OH)2
4. NaCl

Explanation

Calcium carbonate is formed aft er two to three days of white washing and gives a shiny finish to the walls. It is interesting to note that the chemical formula for marble is also CaCO3.

22. What is the product of the reaction?

Ca (OH)2(aq) + CO2(g) →____ +______

1. CaO, H2O
2. CaCO3, H2O
3. Ca (OH)2, H2O
4. CaCO3, O2

Explanation

23. What happens when mercury (II) oxide is heated?

1. Mercury metal and oxygen gas is formed
2. Mercury Dioxide is formed
3. Mercury Trioxide is formed
4. None

Explanation

In Thermal Decomposition Reactions, the reactant is decomposed by applying heat. For example, on heating mercury (II) oxide is decomposed into mercury metal and oxygen gas. As the molecule is dissociated by the absorption of heat, it is otherwise called ‘Thermolysis’. It is a class of compound to element/element decomposition. i.e. a compound (Hg O) is decomposed into two elements (Hg and Oxygen).

24. What happens when calcium carbonate is heated?

1. Calcium oxide and carbon dioxide formed
2. Calcium Hydroxide and carbon dioxide
3. Calcium and water
4. Calcium Carboxylic acid formed

Explanation

When calcium carbonate is heated, it breaks down in to calcium oxide and carbon dioxide. It is a type of compound to compound/compound decomposition.

25. Thermal decomposition is_______ reaction

1. Exothermic
2. Endothermic
3. Redox
4. Reduction

Explanation

In thermal decomposition reaction, heat is supplied to break the bonds. Such reactions, in which heat is absorbed, are called ‘Endothermic reactions’

26. Assertion(A): Decomposition of sodium chloride occurs on passing electric current through its

aqueous solution

Reason(R): In some of the decomposition reactions, electrical energy is used to bring about the

Reaction

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

In some of the decomposition reactions, electrical energy is used to bring about the reaction. For example, decomposition of sodium chloride occurs on passing electric current through its aqueous solution. Sodium chloride decomposes in to metallic sodium and chlorine gas. Th is process is termed as ‘Electrolysis’.

27. The decomposition reaction is called as_____

1. Thermolysis
2. Photolysis
3. Electrolysis
4. Photosynthesis

Explanation

Light is another form of energy, which facilitates some of the decomposition reactions. As the decomposition is caused by the light, this kind of reaction is also called ‘Photolysis’.

28. What will be the colour of silver bromide in absence of sunlight?

1. Grey colour
2. Light yellow
3. Light green
4. Silver brown

Explanation

Th e yellow coloured silver bromide turns into grey coloured silver metal when placed in sunlight. It is also a compound to element/element decomposition.

29. Which of the following is single displacement reaction?

1. Ca(OH)2(aq) + CO2(g) → CaCO3(s) + H2 O(I)
2. 2AgBr(s) → 2Ag(s) + Br2(g)
3. Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)
4. Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)
5. 1, 2
6. 1, 3
7. 2, 3
8. 2, 4

Explanation

Single Displacement Reactions is a reaction between an element and a compound. When they react, one of the elements of the compound-reactant is replaced by the element-reactant to form a new compound and an element.

Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)

Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)

30. Arrange the most reactive elements in order:

1. Potassium
2. Zinc
3. Hydrogen
4. Platinum
5. 1, 3, 4, 2
6. 2, 3, 4, 1
7. 4, 3, 2, 1
8. 1, 2, 3, 4

Explanation

31. 2NaCl(aq) + F2(g) →

1. NaF, Cl2
2. 2NaF, Cl2
3. 2NaF, Cl3
4. NaF2, 2Cl

Explanation

2NaCl(aq) + F2(g) → 2NaF(aq) + Cl2(g)

2NaF(aq) + Cl2(g) → 2NaCl(aq) + F2(g) Th e first reaction involves the displacement of chlorine from NaCl, by fluorine. In the second reaction, chlorine displaces fluorine from NaF. Out of these two, the second reaction will not occur. Because, fluorine is more active than chlorine and occupies the upper position in the periodic table.

32. Which of the following statement is correct?

1. When two compounds react, if their ions are interchanged, then the reaction is called double displacement reaction.
2. The ion of one compound is replaced by the ion of another compound
3. This reaction is also called ‘Metathesis Reaction’
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

When two compounds react, if their ions are interchanged, then the reaction is called double displacement reaction. Th e ion of one compound is replaced by the ion of another compound. Ions of identical charges are only interchanged, i.e., a cation can be replaced by other cations. Th is reaction is also called ‘Metathesis Reaction’

33. For a double displacement reaction to take place_____

1. Both products must be precipitate alone
2. One of the products, must be water alone
3. One of the products must be a precipitate or water
4. None

Explanation

For a double displacement reaction to take place, one of the products must be a precipitate or water. By this way, there are major classes of double displacement reactions. They are:

• Precipitation Reactions
• Neutralization Reactions

34. Which of the following statement about decomposition reaction is correct?

1. A single reactant is decomposed to form one or more products
2. Energy is released
3. Single compound is the reactant
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

35. What is the colour of lead (II) iodide?

1. Blue
2. Yellow
3. Red
4. Green

Explanation

When the clear aqueous solutions of potassium iodide and lead (II) nitrate are mixed, a double displacement reaction takes place between them.

Pb(NO3 )2(aq) + 2KI(aq) → PbI2(s)↓ + 2KNO3(aq)

Potassium and lead displace or replace one other and form a yellow precipitate of lead (II) iodide

36. The product of Neutralization Reaction is always______

1. Acid
2. Base
3. Salt
4. None

Explanation

In your lower classes, you have learned the reaction between an acid and a base. It is another type of displacement reaction in which the acid reacts with the base to form a salt and water. It is called ‘neutralization reaction’ as both acid and base neutralize each other.

37. NaOH(aq) + HCl(aq) →

1. NaH2, OH
2. NaCl, H2O
3. HCl, Na (OH)2
4. HOCl, Na

Explanation

Reaction of sodium hydroxide with hydrochloric acid is a typical neutralization reaction. Here, sodium replaces hydrogen from hydrochloric acid forming sodium chloride, a neutral soluble salt.

NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

38. Which of the following statement is correct?

1. A combustion reaction is one in which the reactant rapidly combines with oxygen to form one or more oxides and energy
2. Combustion reactions are majorly used as heat energy sources in many of our day to day activities.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

A combustion reaction is one in which the reactant rapidly combines with oxygen to form one or more oxides and energy (heat). So, in combustion reactions one of the reactants must be oxygen. Combustion reactions are majorly used as heat energy sources in many of our day to day activities. For instance, we use LPG gas for domestic cooking purposes.

39. Which of the following are the mixture of LPG?

1. Propane
2. Butane
3. Propylene
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

LPG is a mixture of hydrocarbon gases like propane, butane, propylene, etc. All these hydrocarbons burn with oxygen to form carbon dioxide and water.

C3 H8(g) + 5O2(g) → 3CO2(g) + 4H2 O(g) + Heat

40. Which of the following statement is correct?

1. All combustion reactions are oxidation reaction
2. All oxidation reactions are not combustion
3. Combustion reaction is an exothermic reaction
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Since heat is evolved, it is an exothermic reaction. As oxygen is added, it is also an oxidation. So, combustion may be called as an exothermic oxidation.

41. Which of the following is a combustion?

1. Digestion of Food
2. Rusting of iron
3. Evaporation of water
4. 1, 2
5. 1, 3
6. 2, 3
7. None

Explanation

(i) Digestion of Food

(ii) Rusting of iron

None of the reaction is combustion reaction, because digestion food is endothermic reaction and rusting of iron does not produce energy.

42. Assertion(A): Liquid water freezes into ice, it is a permanent change

Reason(R): Physical changes can be reversed easily.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is wrong and (R) is correct

Explanation

You know that innumerable changes occur every day around us. For example, liquid water freezes into ice, but then ice melts into liquid water. In other words, freezing is reversed. So, it is not a permanent change. Moreover, it is a physical change. Physical changes can be reversed easily.

43. Which of the following statement is correct?

1. The carbon compounds present in the wood are burnt into carbon dioxide gas and water.
2. Some chemical reactions can be reversed
3. On recharging the mobile, these chemical reactions are reversed.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Let us consider the burning of a wood. The carbon compounds present in the wood are burnt into carbon dioxide gas and water. Can we get back the wood immediately from carbon dioxide and water? We cannot. So, it is a permanent change. In most of the cases, we cannot. But, some chemical reactions can be reversed. Our mobile phone gets energy from its lithium-ion battery by chemical reactions. It is called discharging. On recharging the mobile, these chemical reactions are reversed. Thus, chemical reactions may be reversed under suitable conditions. Hence, they are grouped into two categories such as reversible and irreversible reactions.

44. Which of the following statement about reversible reaction is correct?

1. It is a reaction that can be reversed
2. A reversible reaction is represented by a double arrow with their heads in the direction opposite to each other
3. The products can be converted back to the reactants
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

A reversible reaction is a reaction that can be reversed, i.e., the products can be converted back to the reactants. A reversible reaction is represented by a double arrow with their heads in the direction opposite to each other.

45. Which of the following statement about forward reaction is the decomposition of PCl5 and the

backward reaction is the combination of PCl3 and Cl2 is correct?

1. Initially, the forward reaction proceeds faster than the backward reaction
2. After sometimes, the speed of both the reactions become equal.
3. PCl5 cannot be completely converted into the products as the reaction is reversed
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The forward reaction is the decomposition of PCl5 and the backward reaction is the combination of PCl3 and Cl2. Initially, the forward reaction proceeds faster than the backward reaction. Aft er sometimes, the speed of both the reactions become equal. So, PCl5 cannot be completely converted into the products as the reaction is reversed. It is a reversible reaction. Th e actual measurements of the given reaction show that the reaction is at equilibrium, but the amount of PCl5 is more than that of PCl3 and Cl2.

46. If hydrogen peroxide is poured on a wound, it decomposes into______

1. Water and oxygen
2. Hydrogen and oxygen
3. Hydrochloric acid
4. Hydrogen and water

Explanation

If hydrogen peroxide is poured on a wound, it decomposes into water and oxygen. Th e gaseous oxygen bubbles away as it is formed and thus prevent the formation of H2 O2. Thus, more amount of product can be obtained in a reversible reaction by the periodical removal of one of the products or the periodical addition of the reactants.

47. Which of the following statement about irreversible reaction is correct?

1. The reaction that cannot be reversed is called irreversible reaction.
2. The combustion of coal into carbon dioxide and water is an example of irreversible reaction
3. Backward reaction is not possible in this case
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The reaction that cannot be reversed is called irreversible reaction. Th e irreversible reactions are unidirectional, i.e., they take place only in the forward direction. Consider the combustion of coal into carbon dioxide and water.

C(s) + O2(g) → CO2(g) + Heat

In this reaction, solid coal burns with oxygen and gets converted into carbon dioxide gas and water. As the product is a gas, as soon as it is formed it escapes out of the reaction container. It is extremely hard to decompose a gas into a solid. Th us, the backward reaction is not possible in this case. So, it is an irreversible reaction.

48. Which of the following statement about reversible reaction is correct?

1. It can be reversed under suitable conditions.
2. It is fast.
3. It attains equilibrium.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

49.

What does the negative sign indicate?

1. Increase in product
2. Decrease in reactant
3. Decrease in both product and reactant
4. None

Explanation

Where, [A] – Concentration of A [B] – Concentration of B

The negative sign indicates the decrease in the concentration of A with time. The positive sign indicates the increase in the concentration of B with time.

50. Which of the following statement is correct?

1. Faster the reaction, more will be the amount of the product in a specified time.
2. Rate of reaction is also important for a food processor who hopes to slow down the reactions that cause food to spoil.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Faster the reaction, more will be the amount of the product in a specified time. So, the rate of a reaction is important for a chemist for designing a process to get a good yield of a product. Rate of reaction is also important for a food processor who hopes to slow down the reactions that cause food to spoil.

51. Iron gets rusted faster in__________

1. Acid
2. Bases
3. Water
4. None

Explanation

The rate of a reaction can be changed. For example, iron gets rusted faster in an acid than in water. Some factors influence the rate of a reaction.

52. Which of the following are the factors that affect rate of a reaction?

1. Catalyst
2. Pressure
3. Nature of the reactants
4. Temperature
5. 1, 2, 3
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

Important factors that affect rate of a reaction are

• Nature of the reactants
• Concentration of the reactants
• Temperature
• Catalyst
• Pressure
• Surface area of the reactants

53. Which of the following reacts faster with sodium?

1. HCl
2. Acetic acid
3. Formic acid
4. None

Explanation

The reaction of sodium with hydrochloric acid is faster than that with acetic acid. Hydrochloric acid is a stronger acid than acetic acid and thus more reactive. So, the nature of the reactant influence the reaction rate.

2Na(s) + 2HCl(aq) → 2NaCl(aq)+ H2 (g) (fast)

2Na(s) + 2CH3 COOH (aq) → 2CH3 COONa (aq)+ H2(g)(slow)

54. Assertion(A): Changing the amount of the reactants also increases the reaction rate

Reason(R): More the concentration, more particles per volume exist in it and hence faster the

reaction.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is wrong and (R) is correct

Explanation

Changing the amount of the reactants also increases the reaction rate. The amount of the substance present in a certain volume of the solution is called ‘concentration’. More the concentration, more particles per volume exist in it and hence faster the reaction. Granulated zinc reacts faster with 2M hydrochloric acid than 1M hydrochloric acid.

55. Assertion(A): Calcium carbonate reacts slowly with hydrochloric acid at room temperature. When heated reaction will be faster.

Reason(R): Most of the reactions go faster at higher temperature.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is wrong and (R) is correct

Explanation

Most of the reactions go faster at higher temperature. Because adding heat to the reactants provides energy to break more bonds and thus speed up the reaction. Calcium carbonate reacts slowly with hydrochloric acid at room temperature. When the reaction mixture is heated the reaction-rate increases.

56. Assertion(A): Food kept at room temperature spoils faster than that kept in the refrigerator

Reason(R): Most of the reactions go faster at higher temperature.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is wrong and (R) is correct

Explanation

Food kept at room temperature spoils faster than that kept in the refrigerator. In the refrigerator, the temperature is lower than the room temperature and hence the reaction rate is less.

57. If the reactants are gases, increasing their pressure______ the reaction rate.

1. Increases
2. Decreases
3. Initially increase then decreases
4. None

Explanation

If the reactants are gases, increasing their pressure increases the reaction rate. This is because, on increasing the pressure the reacting particles come closer and collide frequently.

58. On heating potassium chlorate, it decomposes into_______

1. KCl, O2
2. KOH, Cl2
3. KOCl2
4. KOH, H2

Explanation

A catalyst is a substance which increases the reaction rate without being consumed in the reaction. In certain reactions, adding a substance as catalyst speeds up the reaction. For example, on heating potassium chlorate, it decomposes into potassium chloride and oxygen gas, but at a slower rate. If manganese dioxide is added, it increases the reaction rate.

59. Which of the following statement is correct?

1. When solid reactants are involved in a reaction, their powdered form reacts more readily
2. Because, powdering of the reactants increases the surface area and more energy is available on collision of the reactant particles
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

When solid reactants are involved in a reaction, their powdered form reacts more readily. For example, powdered calcium carbonate reacts more readily with hydrochloric acid than marble chips. Because, powdering of the reactants increases the surface area and more energy is available on collision of the reactant particles. Thus, the reaction rate is increased.

60. Which of the following statement is correct?

1. In a reversible reaction, both forward and backward reactions take place simultaneously
2. When the rate of the forward reaction becomes equal to the rate of backward reaction, then no more product is formed.
3. This stage of the reaction is called ‘equilibrium state’.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

In a reversible reaction, both forward and backward reactions take place simultaneously. When the rate of the forward reaction becomes equal to the rate of backward reaction, then no more product is formed. This stage of the reaction is called ‘equilibrium state’. After this stage, no net change in the reaction can occur and hence in the amount of the reactants and products. Since this equilibrium is attained in a chemical reaction, it is called ‘Chemical Equilibrium’

Rate of forward reaction = Rate of backward reaction

61. Assertion(A): Initially the rate of the backward reaction is greater than the rate of the forward

Reaction

Reason(R): During the course of reaction, the concentration of the reactants decreases and the

concentration of the products increases.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is wrong and (R) is correct

Explanation

Initially the rate of the forward reaction is greater than the rate of the backward reaction. However, during the course of reaction, the concentration of the reactants decreases and the concentration of the products increases. Since the rate of a reaction is directly proportional to the concentration, the rate of the forward reaction decreases with time, whereas the rate of the backward reaction increases.

62. Which of the following statement is correct?

1. Not only chemical changes, physical changes also may attain equilibrium.
2. Physical equilibrium is a state of a physical change at which the volume of all the phases remain unchanged.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Not only chemical changes, physical changes also may attain equilibrium. When water kept in a closed vessel evaporates, it forms water vapour. No water vapour escapes out of the container as the process takes place in a closed vessel. So, it builds up the vapour pressure in the container. At one time, the water vapour condenses back into liquid water and when the rate of this condensation becomes equal to that of vapourisation, the process attains equilibrium. At this stage, the volume of the liquid and gaseous phases remain constant. Since it is a physical change, the equilibrium attained is called ‘Physical Equilibrium’. Physical equilibrium is a state of a physical change at which the volume of all the phases remain unchanged.

63. Which of the following properties remain unchanged in a equilibrium reaction?

1. Colour
2. Viscosity
3. Density
4. Pressure
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

Characteristics of equilibrium:

• In a chemical equilibrium, the rates of the forward and backward reactions are equal.
• The observable properties such as pressure, concentration, colour, density, viscosity etc., of the system remain unchanged with time.
• The chemical equilibrium is a dynamic equilibrium, because both the forward and backward reactions continue to occur even though it appears static externally.
• In physical equilibrium, the volume of all the phases remain constant.

64. In Aerated soft drinks dissolved carbon dioxide in the form of______

1. Carbonic acid
2. Carboxylic acid
3. Epoxy resin
4. Hydrogen chloride

Explanation

Aerated soft drinks contain dissolved carbon dioxide in a pop bottle (Soda). When the bottle is sealed, the dissolved carbon dioxide (in the form of carbonic acid) and gaseous CO2 are in equilibrium with each other. When you open the bottle, the gaseous CO2 can escape. So, the dissolved CO2 begins to un-dissolve back to the gas phase trying to replace the gas that was lost, when you opened the bottle. That’s why if you leave it open long enough, it will goes ‘flat’. All the CO2 will be gone, blown away in the air.

65. Which of the following statement is correct?

1. Although pure water is often considered as a non-conductor of electricity, precise measurements show that it conducts electricity to a little extent
2. This conductivity of water has resulted from the self-ionisation of water
3. The proton gets dissolved in water forming the hydronium ion
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Although pure water is often considered as a non-conductor of electricity, precise measurements show that it conducts electricity to a little extent. This conductivity of water has resulted from the self-ionisation of water. Self-ionisation or auto ionisation is a reaction in which two like molecules react to give ions. In the process of ionisation of water, a proton from one water molecule is transferred to another water molecule leaving behind an OH— ion. The proton gets dissolved in water forming the hydronium ion as shown in the following equation:

66. The hydronium ion formed is a______ acid and the hydroxyl ion is a______ base

1. Strong, Weak
2. Weak, Weak
3. Strong, Strong
4. Weak, Strong

Explanation

The hydronium ion formed is a strong acid and the hydroxyl ion is a strong base. So as fast as they are formed, they react again to produce water. Thus, it is a reversible reaction and attains equilibrium very quickly. So, the extent of ionisation is very little and the concentration of the ions produced is also very less.

67. What is the value if ionic product of water?

1. 1.00 × 10^-14
2. 1.00 × 10^14
3. 2.00 × 10^-14
4. 2.00 × 10^14

Explanation

The product of the concentration of the hydronium ion and the hydroxyl ion is called ‘ionic product of water’. It is denoted as ‘Kw’. It is mathematically expressed as follows:

Kw = [H3 O+] [OH-]

Its unit is mol^2 dm^-6. At 25° C, its value is 1.00 × 10^-14.

68. Which of the following decides whether the aqueous solution is acid or base?

1. Hydrogen ion
2. Hydroxyl ions
3. Either a or b
4. None

Explanation

All the aqueous solutions may contain hydrogen and hydroxyl ions due to self-ionisation of water. In addition to this ionisation, substances dissolved in water also may produce hydrogen ions or hydroxyl ions. The concentration of these ions decides whether the solution is acidic or basic.

69. pH scale is a scale for measuring the_____ ion concentration in a solution

1. Hydrogen
2. Hydroxyl
3. Chlorine
4. None

Explanation

pH scale is a scale for measuring the hydrogen ion concentration in a solution. The ‘p’ in pH stands for ‘Potenz’ in German meaning ‘power’. pH notation was devised by the Danish biochemist Sorensen in 1909.

70. Match the following

1. Acids 1. pH equal to 7
2. Bases 2. pH greater than 7
3. A neutral solution 3. pH less than 7
4. 2, 1, 3
5. 2, 3, 1
6. 3, 2, 1
7. 1, 2, 3

Explanation

pH scale is a set of numbers from 0 to 14 which is used to indicate whether a solution is acidic, basic or neutral.

• Acids have pH less than 7
• Bases have pH greater than 7
• A neutral solution has pH equal to 7

The pH is the negative logarithm of the hydrogen ion concentration.

i.e. pH = –log10[H+]

71. Match the following acids with their pH level:

1. HCl (4%) 1. 4.2
2. Vinegar 2. 0
3. Human saliva 3. 3
4. Tomato juice 4. 6-8
5. 2, 1, 3, 4
6. 2, 3, 4, 1
7. 2, 4, 1, 3
8. 1, 3, 4, 2

Explanation

72. Match the following with their pH level:

1. Blood plasma 1. 5.6
2. Drain cleaner 2. 10
3. Milk of magnesia 3. 13
4. Coffee 4. 7.4
5. 4, 1, 2, 3
6. 4, 3, 2, 1
7. 2, 3, 1, 4
8. 3, 1, 2, 4

Explanation

73. Which of the following statement is correct?

1. The pH of a solution can be determined by using a universal indicator.
2. It comes in the form of a solution or a pH paper
3. The colour of the solution on the pH paper is compared with the colour chart and the pH value is read from it. The pH values thus obtained are only approximate values.
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

The pH of a solution can be determined by using a universal indicator. It contains a mixture of dyes. It comes in the form of a solution or a pH paper. A more common method of measuring pH in a school laboratory is by using the pH paper. A pH paper contains a mixture of indicators. It shows a specific colour at a given pH. A colour guide is provided with the bottle of the indicator or the strips of paper impregnated with it, which are called pH paper strips. Th e test solution is tested with a drop of the universal indicator, or a drop of the test solution is put on the pH paper. The colour of the solution on the pH paper is compared with the colour chart and the pH value is read from it. The pH values thus obtained are only approximate values.

74. Match the following

1. Our body works within the pH range 1] 7.4
2. pH of blood is ranges b/w 2] 7.0 to 7.8
3. Ideal pH for blood 3] 7.35 to 7.45
4. 2, 1, 3
5. 2, 3, 1
6. 3, 1, 2
7. 1, 3, 2

Explanation

Our body works within the pH range of 7.0 to 7.8. Living organisms can survive only in a narrow range of pH change. Different body fluids have different pH values. For example, pH of blood is ranging from 7.35 to 7.45. Any increase or decrease in this value leads to diseases. The ideal pH for blood is 7.4.

75. Which acid is produced by stomach?

1. Formic acid
2. HCl
3. H2SO4
4. HOCl

Explanation

It is very interesting to note that our stomach produces hydrochloric acid. It helps in the digestion of food without harming the stomach.

76. What is the pH of stomach fluid?

1. 2.0
2. 4.2
3. 3.9
4. 1.0

Explanation

During indigestion the stomach produces too much acid and this causes pain and irritation. pH of the stomach fluid is approximately 2.0.

77. Which of the following statement is correct?

1. pH of the saliva normally ranges between 6.5 to 7.5.
2. White enamel coating of our teeth is calcium carbonate, the hardest substance in our body
3. When the pH of the mouth saliva falls below 5.5, the enamel gets weathered
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

pH of the saliva normally ranges between 6.5 to 7.5. White enamel coating of our teeth is calcium phosphate, the hardest substance in our body. When the pH of the mouth saliva falls below 5.5, the enamel gets weathered. Toothpastes, which are generally basic are used for cleaning the teeth that can neutralise the excess acid and prevent tooth decay.

78. Citrus fruits require slightly____ soil

1. Acidic
2. Basic
3. Alkaline
4. Saline

Explanation

In agriculture, the pH of the soil is very important. Citrus fruits require slightly alkaline soil, while rice requires acidic soil and sugarcane requires neutral soil.

79. The pH of rain water is approximately_____

1. 7
2. 9
3. 4
4. 3

Explanation

The pH of rain water is approximately 7, which means that it is neutral and also represents its high purity. If the atmospheric air is polluted with oxide gases of sulphur and nitrogen, they get dissolved in the rain water and make its pH less than 7. Th us, if the pH of rain water is less than 7, then it is called acid rain. When acid rain fl ows into the rivers it lowers the pH of the river water also.

80. Calculate the pH of 0.01 M HNO3?

1. 2
2. 4
3. 1
4. 5

Explanation

81. The hydroxyl ion concentration of a solution is 1 × 10-9 M. What is the pOH of the solution?

1. 10
2. 11
3. 9
4. 2

Explanation

82. Which of the following is correct?

1. pH + pOH = 14
2. pH + pOH = -14
3. pH – pOH = 14
4. pH * pOH = 14

Explanation

The pH and pOH of a water solution at 25 degree C, are related by the following equation.

pH + pOH = 14

If either the pH or the pOH of a solution is known, the other value can be calculated.

83. A solution has a pOH of 11.76. What is the pH of this solution?

1. 2.24
2. 3.9
3. 3.7
4. 4.9

Explanation

84. Calculate the pH of 0.001 molar solution of HCl

1. 8
2. 3
3. 1
4. 9

Explanation

85. What would be the pH of an aqueous solution of sulphuric acid which is 5 × 10–5 mol litre–1 in

Concentration?

1. 1
2. 8
3. 4
4. 2

Explanation

86. If the pH of a solution is 4.5, what is its pOH?

1. 8.5
2. 7.5
3. 4.5
4. 9.5

Explanation

87. Calculate the pH of a solution in which the concentration of the hydrogen ions is 1.0 × 10–8 mol

Litre^–1.

1. 3
2. 9
3. 1
4. 8

Explanation

10th Science Lesson 11 Questions in English

11] Carbon And Its Compounds

1. In which of the following carbon element is incorporated?

1. Food we eat
2. Medicines we take when ill
3. Domestic and automobile fuels
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Carbon is an inseparable element in human life as we use innumerable number of carbon compounds in our day-to-day life. Because, the food we eat, medicines we take when ill, clothes we wear; domestic and automobile fuels, paint, cosmetics, automobile parts, etc., that we use contain carbon compounds.

2. Which of the following is not a unique feature of carbon?

1. Catenation
2. Tetravalency
3. Multiple bonding
4. 1, 2
5. 2, 3
6. 1 alone
7. None

Explanation

The unique nature of carbon, such as catenation, tetravalency and multiple bonding, enables it to combine with itself or other elements like hydrogen, oxygen, nitrogen, sulphur etc., and hence form large number of compounds. All these compounds are made of covalent bonds. These compounds are called organic compounds.

3. Assertion(A): The number of carbon compounds found in nature and man-made, is much higher

than that of any other element in the periodic table

Reason(R): In-fact there are more than 5 million compounds of carbon.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

The number of carbon compounds found in nature and man-made, is much higher than that of any other element in the periodic table. In-fact there are more than 5 million compounds of carbon.

4. Which of the following are the characteristics of Organic compounds?

1. Organic compounds have a high molecular weight and a complex structure
2. They are highly inflammable in nature
3. They are non-volatile in nature.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Organic compounds have a high molecular weight and a complex structure. They are highly inflammable in nature. They are volatile in nature. Organic compounds can be prepared in the laboratory.

5. Assertion(A): The reactions involving organic compounds proceed at slower rates

Reason(R): Organic compounds are less reactive compared to inorganic compounds

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

Organic compounds are less reactive compared to inorganic compounds. Hence, the reactions involving organic compounds proceed at slower rates.

6. In which of the following organic compounds are insoluble?

1. Water
2. Toluene
3. Ether
4. carbon tetrachloride

Explanation

Organic compounds are mostly insoluble in water, but soluble in organic solvents such as ether, carbon tetrachloride, toluene, etc.

7. Which of the following statement is correct about isomerism?

1. A single molecular formula represents several organic compounds that differ in their physical and chemical properties
2. A single molecular formula represents several organic compounds that differ in their physical property alone
3. A single molecular formula represents several organic compounds that differ in their chemical properties alone
4. None

Explanation

Organic compounds exhibit the phenomenon of isomerism, in which a single molecular formula represents several organic compounds that differ in their physical and chemical properties. They have lower melting point and boiling point when compared to inorganic compounds.

8. Which of the following statement is correct?

1. There are millions of organic compounds known and many new organic compounds are discovered every year in nature or synthesized in laboratory
2. In early days, chemists recognised that compounds having similar structural features have identical chemical properties
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

There are millions of organic compounds known and many new organic compounds are discovered every year in nature or synthesized in laboratory. This may mystify organic chemistry to a large extent. However, a unique molecular structure can be assigned to each compound and it can be listed by using systematic methods of classification and eventually named on the basis of its structural arrangements. In early days, chemists recognised that compounds having similar structural features have identical chemical properties. So, they began to classify compounds based on the common structural arrangements found among them.

9. Which of the following statement is correct?

1. Organic chemistry is the chemistry of catenated carbon compounds.
2. The carbon atoms present in organic compounds are linked with each other through inter- molecular force and thus exist as chains.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Organic chemistry is the chemistry of catenated carbon compounds. The carbon atoms present in organic compounds are linked with each other through covalent bonds and thus exist as chains.

10. A compound have triple bonds between them, then it is_______

1. Unsaturated
2. Saturated
3. Partially saturated
4. None

Explanation

If one or more double bonds or triple bonds exist between the carbon atoms, then the compound is said to unsaturated.

11. In Open chain compounds Carbon atoms are linked in a________

1. Cyclic pattern
2. Linear pattern
3. Rectangular pattern
4. Square pattern

Explanation

Acyclic or Open chain compounds: These are the compounds in which the carbon atoms are linked in a linear pattern to form the chain. If all the carbon atoms in the chain are connected by single bonds, the compound is called as saturated.

12. CH3-CH=CH2, what is the name of the compound?

1. Propane
2. Propene
3. Propyne
4. None

Explanation

13. Which of the following is a carbocyclic compound?

1. Cyclo-butanol
2. Furanol
3. Benzene
4. Benzenol

Explanation

Organic compounds in which the chain of carbon atoms is closed or cyclic are called cyclic compounds. If the chain contains only carbon atoms, such compounds are called carbocyclic compounds. e.g. Benzene, Furan.

14. Which of the following compounds presence makes heterocyclic compounds?

1. Oxygen
2. Nitrogen
3. Sulphur
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

If the chain contains carbon and other atoms like oxygen, nitrogen, sulphur, etc., these compounds are called heterocyclic compounds.

15. Which of the following statement is correct?

1. Carbocyclic compounds are further subdivided into alicyclic and aromatic compounds.
2. Alicyclic compounds contain one or more carbocyclic rings which may be saturated or unsaturated
3. Aromatic compounds contain one or more benzene rings
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Carbocyclic compounds are further subdivided into alicyclic and aromatic compounds. Alicyclic compounds contain one or more carbocyclic rings which may be saturated or unsaturated whereas aromatic compounds contain one or more benzene rings (ring containing alternate double bonds between carbon atoms).

16. Match the following:

1. 1. Furan
2. 2. Cyclo-butane
3. 3. Benzene
4. 2, 1, 3
5. 2, 3, 1
6. 1, 3, 2
7. 3, 1, 2

Explanation

17. Match the following:

1. Saturated carbon atom 1. Cyclo-butane
2. Unsaturated Compound 2. Ethene
3. Heterocyclic Compound 3. Ethane
4. Alicyclic Compounds 4. Pyridine
5. 2, 1, 3, 4
6. 3, 2, 4, 1
7. 2, 1, 3, 4
8. 1, 2, 4, 3

Explanation

18. The organic compounds that are composed of only carbon and hydrogen atoms are called_______

1. Carbo-Hydroxide
2. Hydro-carbon
3. Methyl Carbide
4. None

Explanation

Other than carbon, organic compounds contain atoms like hydrogen, oxygen, nitrogen, etc., bonded to the carbon. The organic compounds that are composed of only carbon and hydrogen atoms are called hydrocarbons.

19. Which of the following statement is correct?

1. The carbon atoms join together to form the framework of the compounds.
2. These are regarded as the parent organic compounds and all other compounds are considered to be derived from hydrocarbons by replacing one or more hydrogen atoms with other atoms or group of atoms
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The carbon atoms join together to form the framework of the compounds. These are regarded as the parent organic compounds and all other compounds are considered to be derived from hydrocarbons by replacing one or more hydrogen atoms with other atoms or group of atoms.

20. Which of the following statement is correct?

1. Alkanes are hydrocarbons, which contain only single bonds
2. The simplest alkane (for n=1) is methane (CH4).
3. They are represented by the general formula Cn H2n
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Alkanes are hydrocarbons, which contain only single bonds. They are represented by the general formula CnH2n + 2 (where n = 1,2, 3, ……). The simplest alkane (for n=1) is methane (CH4). Since, all are single bonds in alkanes, they are saturated compounds.

21. Which of the following statement is correct?

1. The hydrocarbons, which contain one or more C=C bonds are called alkenes
2. These are unsaturated compounds
3. They are represented by the general formula CnH2n
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The hydrocarbons, which contain one or more C=C bonds are called alkenes. These are unsaturated compounds. They are represented by the general formula CnH2n. The simplest alkene contains two carbon atoms (n=2) and is called ethylene (C2H4).

22. ______is the simplest alkyne, which contains two carbon atoms

1. Ethane
2. Ethene
3. Acetylene
4. None

Explanation

The hydrocarbons containing c to c triple bond are called alkynes. They are also unsaturated as they contain triple bond between carbon atoms. They have the general formula CnH2n – 2. Acetylene (C2H2) is the simplest alkyne, which contains two carbon atoms.

23. Match the following

1. Ethane 1. C5H8
2. Propene 2. C3H6
3. Propyne 3. C3H4
4. Pentyne 4. C2H6
5. 1, 3, 2, 4
6. 2, 1, 3, 4
7. 4, 2, 3, 1
8. 4, 1, 3, 2

Explanation

24. Which of the following are Characteristics of hydrocarbons?

1. They are colourless and odourless
2. They undergo combustion reaction with oxygen to form CO2 and water.
3. They are soluble in water
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Characteristics of hydrocarbons:

• They are colourless and odourless
• They undergo combustion reaction with oxygen to form CO2 and water.
• Alkanes are saturated whereas alkenes and alkynes are unsaturated.
• They are insoluble in water.

25. The boiling point of hydrocarbons______

1. Increases with an increase in the number of carbon atoms
2. Increases with a decrease in the number of carbon atoms
3. Decreases with an increase in the number of carbon atoms
4. No changes

Explanation

The boiling point of hydrocarbons increases with an increase in the number of carbon atoms. They undergo combustion reaction with oxygen to form CO2 and water.

26. Which of the following are gases at room temperature?

1. Methane
2. Ethane
3. Octane
4. Both 1 and 2

Explanation

Lower hydrocarbons are gases at room temperature e.g methane, ethane are gases. Alkynes are the most reactive due to the presence of the triple bond.

27. Which of the following is a test to identify saturated and unsaturated compounds?

1. Blue litmus
2. Red litmus
3. Bromine water test
4. Saline water test

Explanation

Identify saturated and unsaturated compounds:

• Take the given sample solution in a test tube
• Add a few drops of bromine water and observe any characteristic change in colour
• If the given compound is unsaturated, it will decolourise bromine water.
• Saturated compounds do not decolourise bromine

28. Which of the following does not decolourise bromine water?

1. Alkane
2. Alkyne
3. Alkene
4. All the above

Explanation

29. Which of the following statement is correct?

1. The structural frameworks of organic compounds are made of carbon and hydrogen, which are relatively less reactive
2. The presence of some other atoms or group of atoms makes the compounds more reactive and thus determines the chemical properties of the compound.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The structural frameworks of organic compounds are made of carbon and hydrogen, which are relatively less reactive. But, the presence of some other atoms or group of atoms makes the compounds more reactive and thus determines the chemical properties of the compound. These groups are called functional groups.

30. Which of the following statement is correct?

1. The chemical properties of an organic compound depend on its functional group
2. The physical properties rely on remaining part of the structure
3. For example, ethane is a hydrocarbon having molecular formula C2H6. If one of its hydrogen is replaced by –OH group, you will get an alcohol.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The chemical properties of an organic compound depend on its functional group whereas its physical properties rely on remaining part of the structure. Carbon to carbon multiple bonds (C=C, C C) also are considered as functional groups as many of the properties are influenced by these bonds. Other functional groups include atoms of halogens, –OH, –CHO, –COOH, etc. For example, ethane is a hydrocarbon having molecular formula C2H6. If one of its hydrogen is replaced by –OH group, you will get an alcohol.

31. A series of compounds containing the same functional group is called a_____

1. Group of organic compounds
2. Class of organic compounds
3. Order of organic compounds
4. None

Explanation

A series of compounds containing the same functional group is called a class of organic compounds. Leaving the functional group, the rest of the structure is represented by ‘R’. Thus, an alcohol is represented by ‘R-OH’.

32. Match the following:

1. 1. Ether
2. 2. Alcohol
3. 3. Carboxylic acids
4. 4. Aldehydes
5. 2, 3, 4, 1
6. 2, 4, 3, 1
7. 1, 3, 4, 2
8. 1, 4, 3, 2

Explanation

33. Match the following:

1. Acetaldehyde 1. CH3COCH3
2. Acetone 2. CH3CHO
3. Methyl acetate 3. CH3OCH3
4. Dimethyl ether 4. CH3COOCH3
5. 2, 4, 3, 1
6. 2, 4, 3, 1
7. 2, 3, 4, 1
8. 3, 1, 4, 2

Explanation

34. Which of the following statement is correct?

1. Homologous series is a group or a class of organic compounds having same general formula
2. They have similar chemical properties in which the successive members differ by a – CH2 group
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Homologous series is a group or a class of organic compounds having same general formula and similar chemical properties in which the successive members differ by a – CH2 group

35. Match the following:

1. Methane 1. CH3(CH2)3CH3
2. Propane 2. CH4
3. Pentane 3. CH3(CH2)2CH3
4. Butane 4. CH3CH2CH3
5. 2, 3, 4, 1
6. 2, 4, 3, 1
7. 2, 1, 3, 4
8. 1, 2, 3, 4

Explanation

36. What is the difference in molecular mass of preceding or succeeding member by one methylene

group?

1. 24 amu
2. 14 amu
3. 10 amu
4. 9 amu

Explanation

Each member of the homologous series differs from the preceding or succeeding member by one methylene group (–CH2) and hence by a molecular mass of 14 amu.

37. Which of the following statement about homologous series is correct?

1. All members of a homologous series contain the same elements and functional group
2. Chemical properties of the members of a homologous series are similar.
3. All the members can be prepared by a common method.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

• All members of a homologous series contain the same elements and functional group.
• They are represented by a general molecular formula. e.g. Alkanes, CnH2n + 2.
• The members in each homologous series show a regular gradation in their physical properties with respect to their increase in molecular mass.
• Chemical properties of the members of a homologous series are similar
• All the members can be prepared by a common method.

38. What is the Latin name of the red ant?

1. Erica
2. Formica
3. Calcite
4. Formalin

Explanation

In ancient days, the names of organic compounds were related to the natural things from which they were obtained. For example, the formic acid was initially obtained by distillation of ‘red ants’. Latin name of the red ant is ‘Formica’. So, the name of the formic acid was derived from the Latin name of its source Later, the organic compounds were synthesized from sources other than the natural sources.

39. What is the full-form of IUPAC?

1. International Union of Physical and Applied Chemistry
2. International Union of Pure and Organic Chemistry
3. International Union of Pure and Applied Chemistry
4. International Union of Physical and Applied Physics

Explanation

Scientists framed a systematic method for naming the organic compounds based on their structures. Hence, a set of rules was formulated by IUPAC (International Union of Pure and Applied Chemistry) for the nomenclature of chemical compounds.

40. The IUPAC name of the any organic compound consists of_____ parts

1. 5
2. 3
3. 6
4. 2

Explanation

The IUPAC name of the any organic compound consists of three parts:

i. Root word

ii. Prefix

iii. Suffix

These parts are combined as per the following sequence to get the IUPAC name of the compound:

41. Which of the following statement about Root word is correct?

1. It is the basic unit, which describes the carbon skeleton.
2. Based on the number of carbon atoms present in the carbon skeleton, most of the names are derived from Greek numerals(except first four)
3. It gives the number of carbon atoms present in the parent chain of the compound and the pattern of their arrangement
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Root word: It is the basic unit, which describes the carbon skeleton. It gives the number of carbon atoms present in the parent chain of the compound and the pattern of their arrangement. Based on the number of carbon atoms present in the carbon skeleton, most of the names are derived from Greek numerals (except the first four).

42. Match the following:

1. Hept- 1. Four
2. But- 2. Nine
3. Pent- 3. Seven
4. Non- 4. Five
5. 3, 1, 4, 2
6. 4, 2, 1, 3
7. 2, 1, 3, 4
8. 1, 2, 4, 3

Explanation

43. Atoms or group of atoms, other than hydrogen, attached to carbon of the parent chain are called___________

1. Substituents
2. Presituent
3. Super sonone
4. Sub sonene

Explanation

The prefix represents the substituents or branch present in the parent chain. Atoms or group of atoms, other than hydrogen, attached to carbon of the parent chain are called substituents.

44. Match the following:

1. Amino 1. -I
2. Bromo 2. -Br
3. Ethyl 3. -NH2
4. Iodo 4. -CH2CH3
5. 2, 1, 3, 4
6. 2, 1, 4, 3
7. 3, 2, 4, 1
8. 1, 4, 2, 3

Explanation

45. Which of the following statement is correct?

1. The suffix forms the end of the name. It is divided into two parts such as (a) Primary suffix and (b) Secondary suffix.
2. Suffix ‘ene’ and ‘yne’ are used for the compounds containing double and triple bonds respectively
3. The secondary suffix describes the functional group of the compound
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The suffix forms the end of the name. It is divided into two parts such as (a) Primary suffix and (b) Secondary suffix. The primary suffix comes after the root word. It represents the nature in carbon to carbon bonding of the parent chain. If all the bonds between the carbon atoms of the parent chain are single, then suffix ‘ane’ has to be used. Suffix ‘ene’ and ‘yne’ are used for the compounds containing double and triple bonds respectively. The secondary suffix describes the functional group of the compound.

46. Match the following:

1. Alcohols 1. -oic acid
2. Aldehydes 2. -one
3. Ketones 3. -al
4. Carboxylic acids 4. -ol
5. 4, 3, 2, 1
6. 4, 1, 2, 3
7. 1, 3, 2, 4
8. 3, 1, 2, 4

Explanation

47. Which of the following is not one of the rules for IUPAC naming organic compounds?

1. Identify the longest chain of carbon atoms to get the parent name (root word)
2. Identify the substituent and use a number followed by a dash and a prefix to specify its location and identity.
3. When the primary and secondary suffixes are joined, the terminal ‘e’ of the primary suffix is removed.
4. None

Explanation

IUPAC rules for naming organic compounds:

Rule1: Identify the longest chain of carbon atoms to get the parent name (root word).

Rule 2: Number the carbon atoms of the parent chain, beginning at the closest end of the substituent or functional group. These are called locant numbers. If both functional group and substituent are present, then the priority will be given to the functional group.

Rule 3: In case of alkenes and alkynes, locate the double bond or triple bond and use its locant number followed by a dash and a primary suffix. The carbon chain is numbered in such a way that the multiple bonds have the lowest possible locant number

Rule 4: If the compound contains functional group, locate it and use its locant number followed by a dash and a secondary suffix

Rule 5: When the primary and secondary suffixes are joined, the terminal ‘e’ of the primary suffix is removed

Rule 6: Identify the substituent and use a number followed by a dash and a prefix to specify its location and identity

48. CH3-CH2-CH2-CH2-CH3, What is the IUPAC name?

1. Pentane
2. Butane
3. Propane
4. Hexane

Explanation

CH3-CH2-CH2-CH2-CH3

Step 1: It is a five- carbon chain and hence the root word is ‘Pent’. (Rule 1)

Step 2: All the bonds between carbon atoms are single bonds, and thus the suffix is ‘ane’. So, its name is Pent + ane = Pentane

49. What is the IUPAC name of the following compound?

1. 2-Methylpentane
2. 2-Ethylpentane
3. 2-Methylpropane
4. 2-ethylpropane

Explanation

50. What is the IUPAC name of the following: CH3-CH2-CH2-CH=CH2

1. Pentane
2. Pent-1-yne
3. Pent-1-ene
4. Pent-2-ene

Explanation

51. What is the IUPAC name of the following?

CH3-CH2-CH2-OH

1. Propan-1-ol
2. Propan-2-ol
3. Propan-1-al
4. Propan-2-al

Explanation

52. What is the IUPAC name of the following compound?

CH3COOH

1. Ethanoic acid
2. Methanoic acid
3. Propanoic acid
4. Methyl ethyl ether

Explanation

53. Match the following

1. Propanol 1. CH3CH2CH2CH2 COOH
2. Propanal 2. CH3CH2CH2OH
3. Pentanone 3. CH3COCH2CH2 CH3
4. Pentanoic acid 4. CH3CH2CHO
5. 2, 1, 3, 4
6. 2, 4, 3, 1
7. 2, 4, 1, 3
8. 1, 2, 3, 4

Explanation

54. Which of the following statement is correct?

1. Ethanol is commonly known as alcohol
2. Its molecular formula is C2H5OH.
3. All alcoholic beverages and some cough syrups contain ethanol.
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

Ethanol is commonly known as alcohol. All alcoholic beverages and some cough syrups contain ethanol. Its molecular formula is C2H5OH. Its structural formula is

55. Which of the following statement is correct?

1. Ethanol is manufactured in industries by the fermentation of molasses
2. Molasses is a by-product obtained during the manufacture of sugar from sugarcane
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Ethanol is manufactured in industries by the fermentation of molasses, which is a by-product obtained during the manufacture of sugar from sugarcane.

56. Molasses contain about _____% of sucrose

1. 25
2. 30
3. 75
4. 65

Explanation

Molasses is a dark coloured syrupy liquid left after the crystallization of sugar from the concentrated sugarcane juice. Molasses contain about 30% of sucrose, which cannot be separated by crystallization.

57. Dilution of molasses is done to bring down the concentration of sugar to about____ percent.

1. 6 to 9
2. 8 to 10
3. 3 to 4
4. 1 to 5

Explanation

Dilution of molasses: Molasses is first diluted with water to bring down the concentration of sugar to about 8 to 10 percent.

58. Which of the following can be added to increase the nitrogen content of the molasses?

1. Ammonium sulphate
2. Ammonium phosphate
3. Nitrous oxide
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Molasses usually contains enough nitrogenous matter to act as food for yeast during the fermentation process. If the nitrogen content of the molasses is poor, it may be fortified by the addition of ammonium sulphate or ammonium phosphate.

59. What is the temperature required in the fermentation tank?

1. 100 degree C
2. 303 K
3. 423 K
4. 321 K

Explanation

The solution obtained after the addition of nitrogen source is collected in large ‘fermentation tanks’ and yeast is added to it. The mixture is kept at about 303K for a few days.

60. The fermented liquid is technically called_____

1. Rectified spirit
2. Wash
3. Soap
4. None

Explanation

During fermentation period, the enzymes invertase and zymase present in yeast, bring about the conversion of sucrose into ethanol. The fermented liquid is technically called wash.

61. Which of the following converts sugar into glucose and fructose?

1. Melatonin
2. Invertase
3. Zymase
4. All the above

Explanation

62. What % of alcohol is contained in wash?

1. 15 to 18 %
2. 12 to 18 %
3. 30 to 60 %
4. 25 to 35 %

Explanation

The fermented liquid that is wash, containing 15 to 18 percent alcohol, is now subjected to fractional distillation.

63. What is the water ethanol percentage composition is rectified spirit?

1. 95.5%, 4.5%
2. 4.5%, 95.5%
3. 92%, 8%
4. 85%, 15%

Explanation

The main fraction drawn is an aqueous solution of ethanol which contains 95.5% of ethanol and 4.5% of water. This is called rectified spirit.

64. Rectified spirit can be converted to absolute alcohol by____

1. Caustic potash
2. Quicklime
3. Caustic soda
4. Slaked lime

Explanation

Rectified spirit mixture is then refluxed over quicklime for about 5 to 6 hours and then allowed to stand for 12 hours. On distillation of this mixture, pure alcohol (100%) is obtained. This is called absolute alcohol.

65. Yeast belongs to which of the following class?

1. Virus
2. Fungi
3. Bacteria
4. All the above

Explanation

Yeasts are single–celled microorganisms, belonging to the class of fungi. The enzymes present in yeasts catalyse many complex organic reactions. Fermentation is conversion of complex organic molecules into simpler molecules by the action of enzymes. E.g. Curdling of milk

66. Which of the following property about ethanol is correct?

1. Ethanol is a colourless liquid, having a pleasant smell and a burning taste.
2. Its boiling point is 78 degree C which is less than ethane
3. It is completely miscible with water in all proportions.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Physical properties of Ethanol:

• Ethanol is a colourless liquid, having a pleasant smell and a burning taste
• It is a volatile liquid. Its boiling point is 780 C (351K), which is much higher than that of its corresponding alkane, i.e. ethane (Boiling Point = 184 K).
• It is completely miscible with water in all proportions.

67. At which temperature ethanol is heated with con H2SO4 gets dehydrated?

1. 500K
2. 443K
3. 343K
4. 243K

Explanation

When ethanol is heated with con H2SO4 at 443K, it loses a water molecule i.e. dehydrated to form ethene.

68. What happens when ethanol is heated with Sodium?

1. O2 is liberated
2. O2 is absorbed
3. H2 is liberated
4. H2 is absorbed

Explanation

Ethanol reacts with sodium metal to form sodium ethoxide and hydrogen gas.

69. During oxidation of Ethanol, the colour of alkaline KMnO4 or acidified K2Cr2O7___

1. Changes from orange to green
2. Changes from green to orange
3. Changes from red to blue
4. Changes from blue to red

Explanation

Ethanol is oxidized to ethanoic acid with alkaline KMnO4 or acidified K2Cr2O7. During this reaction, the orange colour of K2Cr2O7 changes to green. Therefore, this reaction can be used for the identification of alcohols.

70. The reaction of an alcohol with a carboxylic acid gives a compound having____ odour

1. Pungent
2. Fruity
3. Fungai
4. Smoky

Explanation

The reaction of an alcohol with a carboxylic acid gives a compound having fruity odour. This compound is called an ester and the reaction is called esterification. Ethanol reacts with ethanoic acid in the presence of conc. H2SO4 to form ethyl ethanoate, an ester.

71. What is used as catalyst dehydrogenation of ethanol?

1. Iron
2. Cu
3. Bromine
4. Nickel

Explanation

When the vapour of ethanol is passed over heated copper, used as a catalyst at 573 K, it is dehydrogenated to acetaldehyde.

72. Ethanol burns to give______

1. Hydrogen
2. Carbon dioxide
3. Nitrogen
4. Sulphur

Explanation

Ethanol is highly inflammable liquid. It burns with oxygen to form carbon dioxide and water.

73. Which of the following statement about ethanol is correct?

1. It in medical wipes, as an antiseptic
2. It is used for effectively killing micro-organisms like bacteria, fungi, etc., by including it in many hand sanitizers.
3. It is used as a solvent for drugs, oils, fats, perfumes, dyes, etc.
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

Uses of ethanol:

Ethanol is used

• in medical wipes, as an antiseptic.
• as an anti-freeze in automobile radiators
• for effectively killing micro-organisms like bacteria, fungi, etc., by including it in many hand sanitizers.
• as an antiseptic to sterilize wounds in hospitals
• as a solvent for drugs, oils, fats, perfumes, dyes, etc
• to enhance the flavour of food extracts, for example vanilla extract; a common food flavour, which is made by processing vanilla beans in a solution of ethanol and water.

74. What is the percentage of ethanol and methanol in methylated spirit?

1. 95, 5
2. 91, 9
3. 96, 4
4. 87, 13

Explanation

Ethanol is used in the preparation of methylated spirit (mixture of 95% of ethanol and 5% of methanol) rectified spirit (mixture of 95.5% of ethanol and 4.5% of water), power alcohol (mixture of petrol and ethanol) and denatured spirit (ethanol mixed with pyridine).

75. Which of the following is the molecular formula of acetic acid?

1. C2H4O2
2. C2H4O4
3. C4H4O2
4. C2H3O2

Explanation

Ethanoic acid or acetic acid is one of the most important members of the carboxylic acid family. Its molecular formula is C2H4O2. Its structural formula is

76. Which of the following is used as catalyst to prepare ethanoic acid in large scale?

1. Alkaline potassium permanganate
2. Acidified potassium permanganate
3. Alkaline potassium dichromate
4. All the above

Explanation
Ethanoic acid is prepared in large scale, by the oxidation of ethanol in the presence of alkaline potassium permanganate or acidified potassium dichromate.

77. Which of the following are the features of ethanoic acid?

1. Ethanoic acid is a colourless liquid having an unpleasant odour
2. It is sour in taste
3. It is miscible with water in all proportions
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Physical Properties of ethanoic acid:

• Ethanoic acid is a colourless liquid having an unpleasant odour.
• It is sour in taste
• It is miscible with water in all proportions.

78. Assertion(A): Ethanoic acid is also known as glacial acetic acid

Reason(R): On cooling, pure ethanoic acid is frozen to form ice like flakes

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

On cooling, pure ethanoic acid is frozen to form ice like flakes. They look like glaciers, so it is called glacial acetic acid. Its boiling point is higher than the corresponding alcohols, aldehydes and ketones.

79. What happens when Ethanoic acid reacts with metals?

1. Oxygen is liberated
2. Hydrogen is liberated
3. Carbon dioxide is liberated
4. Oxygen is absorbed

Explanation

Ethanoic acid reacts with active metals like Na, Zn, etc., to liberate hydrogen and form sodium ethanoate.

2CH3COOH + Zn → (CH3COO)2 Zn + H2 ↑

2CH3COOH + 2Na → 2CH3COONa + H2 ↑

80. What happens when Ethanoic acid reacts with sodium carbonate and sodium bicarbonate?

1. Oxygen is liberated
2. Hydrogen is liberated
3. Carbon dioxide is liberated
4. Oxygen is absorbed

Explanation

Ethanoic acid reacts with sodium carbonate and sodium bicarbonate, which are weaker bases and liberates CO2, with brisk effervescence.

2CH3COOH + Na2CO3 → 2CH3COONa + CO2↑ + H2O

CH3COOH + NaHCO3 → CH3COONa + CO2↑ + H2O

81. What happens when Ethanoic acid reacts with sodium hydroxide?

1. Water is formed
2. Hydroxylic acid is formed
3. Sodium hydroxide is formed
4. Oxygen is absorbed

Explanation

Ethanoic acid reacts with sodium hydroxide to form sodium ethanoate and water.

CH3COOH + NaOH → CH3COONa + H2O

82. Soda lime_____

1. 3 parts of NaOH, 1 part of CaO
2. 1 part of NaOH, 3 parts of CaO
3. 4 parts of NaOH, 1 part of CaO
4. 3 parts of NaOH, 2 parts of CaO

Explanation

When a sodium salt of ethanoic acid is heated with soda lime (solid mixure of 3 parts of NaOH and 1 part of CaO), methane gas is formed.

83. Which of the following are the uses of Acetic acid?

1. Acetic acid, in lower concentration, is used as a food additive
2. In the manufacture of plastic
3. For coagulating rubber from latex.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Acetic acid, in lower concentration, is used as a food additive, a flavoring agent and a preservative.

Ethanoic acid is used:

• in the manufacture of plastic.
• in making dyes, pigments and paint
• in printing on fabrics.
• as a laboratory reagent.
• for coagulating rubber from latex
• in the production of pharmaceuticals.

84. Which of the following are the uses of Hydrocarbons?

1. As a solvent and an antiseptic agent
2. Fuels like LPG, Petrol, Kerosene.
3. Polymeric materials like tyre, plastic containers
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Organic compounds are inseparable in human life. They are used by mankind or associated at all stages of life right from one’s birth to death. Various classes of organic compounds and their uses in our daily life as follows:

Hydrocarbons

• Fuels like LPG, Petrol, Kerosene.
• Raw materials for various important synthetic materials.
• Polymeric materials like tyre, plastic containers

85. Match the following:

1. Alcohols 1. Pain Killer
2. Aldehydes 2. Antiseptic agent
3. Ketones 3. Raw materials for synthetic materials
4. Ethers 4. Stain Remover
5. 1, 4, 2, 3
6. 2, 3, 1, 4
7. 2, 3, 4, 1
8. 1, 2, 3, 4

Explanation

Alcohols

• As a solvent and an antiseptic agent.
• Raw materials for various important synthetic materials.

Aldehydes

• Formaldehyde as a disinfectant
• Raw materials for synthetic materials

Ketones

• As a solvent
• Stain Remover

Ethers

• Anaesthetic agents.
• Pain Killer

Esters

• All the cooking oils and lipids contain esters.

86. Which of the following statement is correct?

1. Soaps and the Detergents are materials that are used by us for cleaning purposes because pure water alone cannot remove all types of dirt or any oily substance from our body or clothes.
2. They perform their cleaning actions in certain specific conditions.
3. They contain ‘surfactants’, which are compounds with molecules that line up around water to break the ‘surface tension’
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Soaps and the Detergents are materials that are used by us for cleaning purposes because pure water alone cannot remove all types of dirt or any oily substance from our body or clothes. They contain ‘surfactants’, which are compounds with molecules that line up around water to break the ‘surface tension’. Both of them having a different chemical nature. They perform their cleaning actions in certain specific conditions.

87. _____ is a cleaning agent that is composed of one or more salts of fatty acids.

1. Salts
2. Detergent
3. Soap
4. Both b and c

Explanation

Soap is a cleaning agent that is composed of one or more salts of fatty acids. Detergent is a chemical compound or a mixture of chemical compounds, which is used as a cleaning agent, also.

88.Which of the following statement is correct?

1. Soaps are sodium or potassium salts of some long chain carboxylic acids, called fatty acids.
2. A potassium-based soap creates a more water-soluble product than a sodium-based soap
3. Soap requires two major raw materials fat and acid
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Soaps are sodium or potassium salts of some long chain carboxylic acids, called fatty acids. Soap requires two major raw materials: i) fat and ii) alkali. The alkali, most commonly used in the preparation of soap is sodium hydroxide. Potassium hydroxide can also be used. A potassium-based soap creates a more water-soluble product than a sodium-based soap

89. Which of the following is used in the preparation of hard soaps?

1. NaOH
2. CaOH
3. CaO
4. Ca(OH)2

Explanation

Soaps, which are prepared by the saponification of oils or fats with caustic soda (sodium hydroxide), are known as hard soaps. They are usually used for washing purpose

90. Which of the following is used in the preparation of hard soaps?

1. Potassium salts
2. Magnesium salts
3. Sodium salts
4. All the above

Explanation

Soaps, which are prepared by the saponification of oils or fats with potassium salts, are known as soft soaps. They are used for cleansing the body.

91. Which of the following process is used to produce manufacturing of soap?

1. Haber’s process
2. Bayer’s process
3. Kettle process
4. None

Explanation

Kettle process is the oldest method. But, it is still widely used in the small scale preparation of soap. There are mainly, two steps to be followed in this process.

92. Which of the following statement is correct about Saponification process?

1. The oil, which is used in this process, is taken in an iron tank (kettle)
2. The alkaline solution (10%) is added into the kettle, a little in excess
3. The alkaline solution (10%) is added into the kettle, a little in excess
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

The oil, which is used in this process, is taken in an iron tank (kettle). The alkaline solution (10%) is added into the kettle, a little in excess. The mixture is boiled by passing steam through it. The oil gets hydrolysed after several hours of boiling. This process is called Saponification.

93. Which of the following are contained in hard water?

1. Calcium ions
2. Sodium ions
3. Magnesium ions
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Hard water contains calcium and magnesium ions (Ca2+ and Mg2+) that limit the cleaning action of soap. Ordinary soaps when treated with hard water, precipitate as salts of calcium and magnesium. They appear at the surface of the cloth as sticky grey scum. Thus, the soaps cannot be used conveniently in hard water.

94. What happens is formed when hard water reacts with soap?

1. Scrum
2. Scum
3. Drum
4. Dump

Explanation

When combined with soap, hard water develops a thin layer (precipitates of the metal ions) called ‘scum’, which leaves a deposit on the clothes or skin and does not easily rinse away. Over time, this can lead to the deterioration of the fabric and eventually ruin the clothes. On the other hand, detergents are made with chemicals that are not affected by hard water.

95. Which of the following statement about synthetic detergents is correct?

1. Development of synthetic detergents is a big achievement in the field of cleansing.
2. These soaps possess the desirable properties of ordinary soaps and also can be used with hard water and in acidic solutions
3. The detergents do not form precipitates with Ca2+ and Mg2+ present in hard water.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Development of synthetic detergents is a big achievement in the field of cleansing. These soaps possess the desirable properties of ordinary soaps and also can be used with hard water and in acidic solutions. These are salts of sulphonic acids or alkyl hydrogen sulphates in comparison to soap, which are salts of carboxylic acids. The detergents do not form precipitates with Ca2+ and Mg2+ present in hard water. So, the cleansing action of detergents is better than that of soaps.

96. Which of the following statement is correct?

1. Detergents are prepared by adding sulphuric acid to the processed hydrocarbon obtained from petroleum
2. This chemical reaction result in the formation of molecules similar to the fatty acid in soap.
3. An alkali is added to the mixture to produce the ‘surfactant molecules’, which do not bond with the minerals present in the hard water, thus preventing the formation of their precipitates
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Detergents are prepared by adding sulphuric acid to the processed hydrocarbon obtained from petroleum. This chemical reaction result in the formation of molecules similar to the fatty acid in soap. Then, an alkali is added to the mixture to produce the ‘surfactant molecules’, which do not bond with the minerals present in the hard water, thus preventing the formation of their precipitates.

97. Which of the following enable the removal of certain stains from the cloth?

1. Sodium chloride
2. Sodium perborate
3. Sodium Per-oxide
4. Sodium hydroxide

Explanation

Oxygen bleaches, such as ‘sodium perborate’, enable the removal of certain stains from the cloth. Sodium sulphate is added to prevent the caking of the detergent powder. Enzymes are added to break down some stains caused by biological substances like blood and vegetable juice.

98. Which of the following in ‘surfactant’ prevent corrosion in washing machine?

1. Sodium chloride
2. Sodium perborate
3. Sodium silicate
4. Sodium hydroxide

Explanation

Sodium silicate, which prevents the corrosion and ensures that the detergent does not damage the washing machine. Fluorescent whitening agents that give a glow to the clothes.

99. Which of the following statement is incorrect?

1. A soap molecule contains two chemically distinct parts that interact differently with water
2. Non-polar end, which is a short head with a carboxylate group (–COONa)
3. Polar end having the long tail made of the hydrocarbon chain
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

A soap molecule contains two chemically distinct parts that interact differently with water. It has one polar end, which is a short head with a carboxylate group (–COONa) and one non-polar end having the long tail made of the hydrocarbon chain.

100. Which of the following statement is incorrect?

1. The polar end is hydrophilic in nature and this end is attracted towards water.
2. The non-polar end is hydrophobic in nature
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The polar end is hydrophilic (Water loving) in nature and this end is attracted towards water. The non-polar end is hydrophobic (Water hating) in nature and it is attracted towards dirt or oil on the cloth, but not attracted towards water. Thus, the hydrophobic part of the soap molecule traps the dirt and the hydrophilic part makes the entire molecule soluble in water.

101. Which of the following statement is correct?

1. When a soap or detergent is dissolved in water, the molecules join together as clusters called ‘micelles’
2. Their long hydrocarbon chains attach themselves to the oil and dirt.
3. The dirt is thus surrounded by the non-polar end of the soap molecules
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

When a soap or detergent is dissolved in water, the molecules join together as clusters called ‘micelles’. Their long hydrocarbon chains attach themselves to the oil and dirt. The dirt is thus surrounded by the non-polar end of the soap molecules. The charged carboxylate end of the soap molecules makes the micelles soluble in water. Thus, the dirt is washed away with the soap.

102. Which of the following statement about advantages of detergents over soaps is correct?

1. They can be used in both hard and soft water and can clean more effectively in hard water than soap.
2. Do not leave any soap scum on the tub or clothes.
3. They can be used for washing woollen garments, whereas soap cannot be used.
4. All the above

Explanation

Detergents are better than soaps because they:

• can be used in both hard and soft water and can clean more effectively in hard water than soap.
• can also be used in saline and acidic water
• do not leave any soap scum on the tub or clothes.
• dissolve freely even in cool water and rinse freely in hard water.
• can be used for washing woollen garments, whereas soap cannot be used.
• have a linear hydrocarbon chain, which is biodegradable.
• are active emulsifiers of motor grease.

103. Which of the following statement about soap is correct?

1. It is prepared from animal fats or vegetable oils
2. It has rich foaming capacity.
3. Soaps are biodegradable
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

104. Which of the following statement about detergent is correct?

1. It is sodium salts of sulphonic acids.
2. It has rich foaming capacity
3. It is prepared from hydrocarbons obtained from crude oil.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

105. Which of the following statement about TFM of soap is correct?

1. TFM means TOTAL FATTY MATTER
2. It is the one of the important factors to be considered to assess the quality of soap
3. A soap, which has lower TFM, is a good bathing soap
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

TFM means TOTAL FATTY MATTER. It is the one of the important factors to be considered to assess the quality of soap. A soap, which has higher TFM, is a good bathing soap.

10th Science Lesson 12 Questions in English

12] Plant Anatomy And Plant Physiology

1. Which of the following is not organised correctly?

1. Molecules into organelles
2. Cells into tissues
3. Tissues into organs
4. 1, 2
5. 1, 3
6. 2, 3
7. None

Explanation

Plants exhibits varying degrees of organization. Atoms are organized into molecules, molecules into organelles, organelles into cells, cells into tissues and tissues into organs.

2. Who among the following is known as Father of Plant Anatomy?

1. Carl Linnaeus
2. William Brown
3. Nehemiah Grew
4. Robert Brown

Explanation

The first account of internal structure of plants was published by English Physician Nehemiah Grew. He is known as Father of Plant Anatomy. Plant anatomy (Gk Ana = as under; Temnein = to cut) is the study of internal structure of plants.

3. Which of the following statement about Tissues is correct?

1. Tissues are the group of cells that are similar in structure and origin alone
2. Plant tissues can be broadly classified into Meristematic tissue and Permanent tissue
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Tissues are the group of cells that are similar or dissimilar in structure and origin, but perform similar function. Plant tissues can be broadly classified into two, based on their ability to divide. They are i) Meristematic tissue ii) Permanent tissue.

4. Who among the following classified tissue system in plants into three types?

1. Carl Linnaeus
2. William Brown
3. Sachs
4. Robert Brown

Explanation

Sachs (1875) classified tissue system in plants into three types:

i) Dermal or Epidermal tissue system

ii) Ground tissue system

iii) Vascular tissue system

5. Which of the following statement about Dermal Tissue System is correct?

1. It consists of epidermis, stomata and epidermal outgrowths
2. Epidermis is the outer most layer
3. Trichomes and root hairs are the epidermal outgrowths
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Dermal or Epidermal Tissue System consists of epidermis, stomata and epidermal outgrowths. Epidermis is the outer most layer. It has many minute pores called stomata. Cuticle is present on the outer wall of epidermis to check evaporation of water. Trichomes and root hairs are the epidermal outgrowths.

6. Which of the following are the functions of Dermal Tissue System?

1. Protection
2. Regeneration
3. Prevention of water loss
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

7. Which of the following are included in Ground Tissue System?

1. Xylem tissue
2. Collenchyma tissue
3. Parenchyma tissue
4. Sclerenchyma tissue
5. 1, 2, 3
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

8. Which of the following are the functions of Vascular Tissue System?

1. Support
2. Transport of water and minerals
3. Transport of food
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

9. _____ helps in transpiration.

1. Cuticle
2. Root hairs
3. Epidermis
4. Stomata

Explanation

Functions of Epidermal Tissue System:

• Epidermis protects the inner tissues
• Stomata helps in transpiration.
• Root hairs help in absorption of water and minerals.

10. Which of the following are not included in Ground Tissue System?

1.  Cortex
2. Endodermis
3. Pith
4. 1, 2
5. 1, 3
6. All the above
7. None

Explanation

Ground Tissue System includes all the tissues of the plant body except epidermal and vascular tissues like (i) Cortex (ii) Endodermis (iii) Pericycle (iv) Pith

11. Which of the following statement is correct?

1. Phloem conducts water and minerals to different parts of the plant
2. Xylem conducts food materials to different parts of the plant.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Vascular Tissue System It consists of xylem and phloem tissues. They are present in the form of bundles called vascular bundles. Xylem conducts water and minerals to different parts of the plant. Phloem conducts food materials to different parts of the plant.

12. How many types of vascular bundles are there in Vascular Tissue System?

1. 5
2. 3
3. 2
4. 6

Explanation

In Vascular Tissue System, there are three different types of vascular bundles namely (i) Radial (ii) Conjoint (iii) Concentric

13. Which of the following statement is correct?

1. In Radial Bundles, Xylem and phloem are present in different radii alternating with each other
2. In Conjoint bundles, Xylem and phloem lie on the same radius.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Radial Bundles:

Xylem and phloem are present in different radii alternating with each other. e.g. roots

Conjoint bundles:

Xylem and phloem lie on the same radius. There are two types of conjoint bundles.

14. Which of the following statement about Collateral conjoint bundles is correct?

1. Xylem lies towards the centre and phloem lies towards the periphery.
2. When cambium is present in collateral bundles, it is called open.
3. When collateral bundle without cambium is called closed.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Collateral conjoint bundles:

Xylem lies towards the centre and phloem lies towards the periphery. When cambium is present in collateral bundles, it is called open. e.g. dicot stem and collateral bundle without cambium is called closed. e.g. monocot stem

15. Which of the following is an example of Bicollateral Conjoint bundles?

1. Onion
2. Rice
3. Cucurbita
4. Garlic

Explanation

In Bicollateral type of bundle, the phloem is present on both outer and inner side of xylem. e.g. Cucurbita

16. Which of the following statement is correct?

1. In Dracaena, Xylem surrounds phloem.
2. In Ferns, Phloem surrounds xylem
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

In Concentric Vascular bundle is one in which xylem completely surrounds the phloem or vice-versa is called concentric vascular bundle. It is of two types:

1. Amphivasal: Xylem surrounds phloem. e.g. Dracaena

2. Amphicribral: Phloem surrounds xylem. e.g. Ferns

17. In which of the following, Protoxylem lies towards the centre and metaxylem lies towards the

periphery?

1. Roots
2. Stem
3. Leaf
4. All the above

Explanation

Endarch: Protoxylem lies towards the centre and metaxylem lies towards the periphery. e.g. stem.

Exarch: Protoxylem lies towards the periphery and metaxylem lies towards the centre. e.g. roots.

18. Which of the following are absent in Epiblema of Dicot Root?

1. Cuticle
2. Stomata
3. Unicellular root hairs
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

A thin transverse section of dicot root shows the following structures:

Epiblema: It is the outermost layer. Cuticle and stomata are absent. Unicellular root hairs are present. It is also known as Rhizodermis or Piliferous layer

19. Which of the following stores food and water?

1. Cortex
2. Endodermis
3. Epiblema
4. Stele

Explanation

Cortex is a multi-layered large zone made of thin-walled parenchymatous cells with intercellular spaces. It stores food and water.

20. Which of the following statement about Endodermis is correct?

1. It is the innermost layer of cortex.
2. It helps in the movement of water and dissolved salts from cortex into xylem
3. The cells are barrel – shaped, closely packed
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Endodermis is the innermost layer of cortex. The cells are barrel – shaped, closely packed, and show band like thickenings on their radial and inner tangential walls called casparian strips. It helps in the movement of water and dissolved salts from cortex into xylem

21. Which of the following includes pericycle and vascular bundle?

1. Cortex
2. Endodermis
3. Epiblema
4. Stele

Explanation

Stele is a part of dicot root. All tissues inner to endodermis constitute stele. It includes pericycle and vascular bundle

22. ______ is the site of origin of lateral roots.

1. Pericycle
2. Vascular bundle
3. Pith
4. All the above

Explanation

Pericycle: Inner to endodermis lies a single layer of pericycle. It is the site of origin of lateral roots.

Pith: Young root contains pith whereas in old root pith is absent.

23. The tissue present between xylem and phloem is called________

1. Piliferous layer
2. Rhizo-dermis
3. Conjunctive tissue
4. None

Explanation

Vascular bundle is radial. Xylem is exarch and tetrach. The tissue present between xylem and phloem is called conjunctive tissue. In dicot root, it is made up of parenchyma.

24. Which of the following statement about Rhizo-dermis of monocot root is correct?

1. It is the outermost layer of the root, and is made up of single layer of thin walled, parenchymatous cell.
2. Stomata and cuticle are present
3. The root hair helps in absorption of water and minerals from the soil
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Epiblema or Rhizo-dermis is the outermost layer of the root, and is made up of single layer of thin walled, parenchymatous cell. Stomata and cuticle are absent. The root hair helps in absorption of water and minerals from the soil. This layer also protects the inner tissues.

25. The cortex of monocot root is composed of______ cells

1. Chlorenchyma
2. Pollenchyma
3. Parenchymatous
4. None

Explanation

Cortex is multi-layered large zone, composed of parenchymatous cells with intercellular spaces. It stores water and food material.

26. Casparian strips of Endodermis are band like thickening made of______

1. Suberin
2. Cutin
3. Stomata
4. Lignin

Explanation

Endodermis is the innermost layer of cortex with characteristic casparian strips and passage cells. Casparian strips are band like thickening made of suberin.

27. Which of the following statement about internal Structure of Monocot Root is correct?

1. Pericycle is a single layer of thin-walled cells
2. Vascular tissues consist of many patches of xylem and phloem arranged radially
3. Stele includes pericycle, vascular tissues and pith.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Stele of Monocot Root: All the tissues inner to endodermis constitute stele. It includes pericycle, vascular tissues and pith.

Pericycle: It is a single layer of thin-walled cells. The lateral roots originate from this layer.

Vascular tissues: It consists of many patches of xylem and phloem arranged radially. The xylem is exarch and poly-arch. The conjunctive tissue is made up of sclerenchyma.

28. _______ contains abundant amount of starch grains

1. Endodermis
2. Stele
3. Pith
4. Cortex

Explanation

Pith is present at the centre. It is made up of parenchyma cells with intercellular spaces. It contains abundant amount of starch grains. It stores food.

29. Which of the following statement is correct about internal Structure of Dicot Stem?

1. Epidermis is the outermost layer
2. It is made up of single layer of Collenchyma cells
3. It is protective in function.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Epidermis in internal Structure of Dicot Stem (Sunflower) is the outermost layer. It is made up of single layer of parenchyma cells, its outer wall is covered with cuticle. It is protective in function.

30. Which of the following statement correct about Cortex of Dicot Stem?

1. It is divided into three regions
2. Hypodermis consists of 3 – 6 layers of collenchyma cells
3. Hypodermis gives mechanical support
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Cortex is divided into three regions.

1. Hypodermis consists of 3 – 6 layers of collenchyma cells. It gives mechanical support.
2. Middle cortex is made up of few layers of chlorenchyma cells. It is involved in photosynthesis due to the presence of chloroplast.
3. Inner cortex is made up of few layers of parenchyma cells. It helps in gaseous exchange and

stores food materials.

31. _______ is the inner most layer of cortex

1. Epidermis
2. Endodermis
3. Ectodermis
4. Hypodermis

Explanation

Endodermis is the inner most layer of cortex it consists of a single layer of barrel shaped cells, these cells contain starch grains. So, it is also called starch sheath.

32. Which of the following are the parts of Stele?

1. Pericycle
2. Vascular bundle
3. Pith
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The central part of the stem inner to endodermis is known as stele. It consists of pericycle, vascular bundle and pith.

33. Pericycle is made of_____ kind of cells

1. Parenchymatous
2. Sclerenchyma
3. Collenchyma
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Pericycle occurs between vascular bundle and endodermis. It is multi-layered, parenchymatous with alternating patches of sclerenchyma.

34. Which of the following statement is correct?

1. Vascular bundles are conjoint, collateral, endarch and open.
2. The large central parenchymatous zone with intercellular spaces is called pith
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Vascular bundles are conjoint, collateral, endarch and open. They are arranged in the form of a ring around the pith. The large central parenchymatous zone with intercellular spaces is called pith. It helps in the storage of food materials.

35. _________ provides mechanical support to plant

1. Parenchyma
2. Collenchyma
3. Sclerenchyma
4. Chlorenchyma

Explanation

Hypodermis of internal Structure of Monocot Stem is made up of few layers of sclerenchyma cells interrupted by chlorenchyma. Sclerenchyma provides mechanical support to plant.

36. Which of the following is absent in Internal Structure of Monocot Stem?

1. Stomata
2. Cuticle
3. Multicellular hairs
4. None

Explanation

Epidermis of internal Structure of Monocot Stem is the outermost layer. It is made up of single layer of parenchyma cells. It is covered with thick cuticle. Multicellular hairs are absent and stomata are also less in number.

37. Xylem vessels in Monocot Stem is arranged in____ shape

1. X
2. V
3. Y
4. X or Y

Explanation

Xylem consists of metaxylem and protoxylem. Xylem vessels are arranged in V or Y shape. In mature vascular bundle, the lower most protoxylem disintegrates and form a cavity. This is called protoxylem lacuna.

38. Which of the following are absent in phloem in Monocot Stem?

1. Sieve tube elements
2. Companion cells
3. Phloem parenchyma
4. Phloem fibers
5. 1, 2
6. 2, 4
7. 3, 4
8. All the above

Explanation

Phloem of monocot stem consists of sieve tube elements and companion cells. Phloem parenchyma, and phloem fibers are absent.

39. Which of the following is not differentiated in monocot stems?

1. Vascular Bundle
2. Cortex
3. Pith
4. Protoxylem lacuna

Explanation

In Ground tissue of the monocot stem, the entire mass of parenchyma cells next to hypodermis and extending to the centre is called ground tissue. It is not differentiated into endodermis, cortex, pericycle and pith. Pith is not differentiated in monocot stems.

40. Which of the following is not correctly matched?

1. Number of Xylem in dicot root is Tetrarch
2. Cambium in dicot root is absent
3. Cambium in monocot root is absent
4. Pith is absent in dicot root

Explanation

41. Match the following tissues with their presence in monocot stem:

1. Hypodermis 1. Present
2. Vascular bundles 2. Collenchymatous
3. Ground tissue 3. Uniform in size
4. Pith 4. Differentiated
5. 2, 1, 3, 4
6. 2, 3, 4, 1
7. 4, 1, 2, 3
8. 3, 1, 2, 4

Explanation

42. Which of the following statement about upper epidermis of Dicot leaf is correct?

1. They are single layered parenchymatous cells without intercellular spaces
2. Stomata are less in number
3. The outer wall of the cells are cuticularized
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Upper epidermis in dicot leaf is the outermost layer made of single layered parenchymatous cells without intercellular spaces. The outer walls of the cells are cuticularized. Stomata are less in number.

43. Which of the following statement about Lower epidermis of dicot leaf is incorrect?

1. It contains numerous stomata.
2. The loss of water vapour is facilitated through this chamber
3. The lower epidermis helps in the exchange of gases
4. 1, 2
5. 1, 3
6. 2, 3
7. None

Explanation

Lower epidermis of dicot leaf is a single layer of parenchymatous cells with a thin cuticle. It contains numerous stomata. Chloroplasts are present only in guard cells. The lower epidermis helps in the exchange of gases. The loss of water vapour is facilitated through this chamber

44. The tissue present between the upper and lower epidermis is called_______

1. Esonophil
2. Mesophyll
3. Epiphyll
4. Exophyll

Explanation

The tissue present between the upper and lower epidermis is called mesophyll. It is differentiated into Palisade parenchyma and Spongy parenchyma.

45. Which of the following statement about Palisade parenchyma is correct?

1. It is found just below the upper epidermis.
2. The cells do not have intercellular spaces and they take part in photosynthesis
3. The cells are elongated
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Palisade parenchyma is found just below the upper epidermis. The cells are elongated. These cells have more number of chloroplasts. The cells do not have intercellular spaces and they take part in photosynthesis

46. Which of the following statement about Spongy parenchyma is correct?

1. It is found below the palisade parenchyma tissue
2. It helps in gaseous exchange
3. Cells are almost spherical or oval and are regularly arranged
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Spongy parenchyma is found below the palisade parenchyma tissue. Cells are almost spherical or oval and are irregularly arranged. Cells have intercellular spaces. It helps in gaseous exchange.

47. In vascular bundle of Dicot leaf xylem lies towards____ and phloem lies towards____

1. Lower epidermis, upper epidermis
2. Upper epidermis, Lower epidermis
3. Lower epidermis, Lower epidermis
4. Upper epidermis, Upper epidermis

Explanation

Vascular bundle (Dicot leaf) of mid-rib is larger. Vascular bundles are conjoint, collateral and closed. Each vascular bundle is surrounded by a sheath of parenchymatous cells called bundle sheath. Each vascular bundle consists of xylem lying towards the upper epidermis and phloem towards the lower epidermis.

48. Which of the following statement about epidermis of monocot leaf is correct?

1. Monocot leaf has upper and lower epidermis.
2. Epidermis is made up of Collenchyma cells.
3. Some cells of upper epidermis are large and thin walled they are known as bulliform cells
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Monocot leaf has upper and lower epidermis. Epidermis is made up of parenchyma cells. Cuticle is present on the outer wall stomata are present on both upper and lower epidermis. Some cells of upper epidermis are large and thin walled they are known as bulliform cells.

49. Which of the following statement about Mesophyll of Monocot leaf is correct?

1. It is the ground tissue that is present between both epidermal layers.
2. These cells contain chloroplasts
3. Mesophyll is not differentiated into palisade and spongy parenchyma
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mesophyll of monocot leaf is the ground tissue that is present between both epidermal layers. Mesophyll is not differentiated into palisade and spongy parenchyma. The cells are irregularly arranged with inter-cellular spaces. These cells contain chloroplasts.

50. Which of the following is Isobilateral leaf?

1. Monocot leaf
2. Dicot leaf
3. Both a and b
4. a or b

Explanation

51. Which of the following is responsible for preparation and storage of food?

1. Mitochondria
2. Plastids
3. Stele
4. Stomata

Explanation

Plastids are double membrane bound organelles found in plants and some algae. They are responsible for preparation and storage of food.

52. Match the following:

1. Chloroplast 1. Colourless
2. Chromoplast 2. Green coloured
3. Leucoplast 3. yellow, red, orange coloured
4. 1, 3, 2
5. 2, 1, 3
6. 2, 3, 1
7. 3, 1, 2

Explanation

There are three types of plastids:

Chloroplast – green coloured plastids

Chromoplast – yellow, red, orange-coloured plastids

Leucoplast – colourless plastids

53. Which of the following statement about Chloroplast is correct?

1. Chloroplasts are green plastids containing green pigment called chlorophyll
2. Their thickness is about 1-2 micro-meter
3. Chloroplasts are oval shaped organelles
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Chloroplasts are green plastids containing green pigment called chlorophyll. Chloroplasts are oval shaped organelles having a diameter of 2-10 micro-meter and a thickness of 1-2 micro-meter.

54. What type of ribosome does Stroma have?

1. 70 S
2. 65 S
3. 50 S
4. 80 S

Explanation

Matrix present inside to the membrane is called stroma. It contains DNA, 70 S ribosomes and other molecules required for protein synthesis.

55. Thylakoids forms a stack of disc like structures called a________

1. Stroma
2. Envelope
3. Grana
4. Stele

Explanation

Thylakoids consists of thylakoid membrane that encloses thylakoid lumen. Thylakoids forms a stack of disc like structures called a grana (singular-granum).

56. Which of the following are the functions of Chloroplast?

1. Photosynthesis
2. Storage of lipids
3. Synthesis of fatty acids
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Functions of Chloroplast:

1. Photosynthesis

2. Storage of starch

3. Synthesis of fatty acids

4. Storage of lipids

5. Formation of chloroplasts

57. Which of the following statement is correct?

1. Photosynthesis (Photo = light; synthesis = to build)
2. It is a process by which autotrophic organisms like green plants, algae and chlorophyll containing bacteria utilize the energy from sunlight to synthesize their own food
3. During this process oxygen is released as a by-product
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Photosynthesis (Photo = light; synthesis = to build) is a process by which autotrophic organisms like green plants, algae and chlorophyll containing bacteria utilize the energy from sunlight to synthesize their own food. In this process, carbon dioxide combines with water in the presence of sunlight and chlorophyll to form carbohydrates. During this process oxygen is released as a by-product.

58. Carbon dioxide + Water 🡪

1. Starch
2. Glucose
3. Water
4. Oxygen
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

59. Which of the following are accessory pigments?

1. Chlorophyll a
2. Chlorophyll b
3. Carotenoids
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Other pigments such as chlorophyll b and carotenoids are called accessory pigments as they pass on the absorbed energy to chlorophyll a (Chl.a) molecule. Reaction centres (Chl. a) and the accessory pigments (harvesting centre) together are called photosystems.

60. Which of the following is/are primary pigment?

1. Chlorophyll a
2. Chlorophyll b
3. Carotenoids
4. Chlorophyll c

Explanation

Pigments involved in photosynthesis are called Photosynthetic pigments. Photosynthetic pigments are of two classes namely, the primary pigments and accessory pigments. Chlorophyll a is the primary pigment that traps solar energy and converts it into electrical and chemical energy. Thus, it is called the reaction centre.

61. The entire process of photosynthesis takes place inside________

1. Mitochondria
2. Ribosome
3. Chloroplast
4. All the above

Explanation

The entire process of photosynthesis takes place inside the chloroplast. The structure of chloroplast is such that the light dependent (Light reaction) and light independent (Dark reaction) take place at different sites in the organelle.

62. Photosynthetic pigments absorb the light energy and convert it into_____

1. ATP
2. ADP
3. NAD
4. NADPH2
5. 1, 3
6. 2, 3
7. 1, 4
8. All the above

Explanation

Photosynthetic pigments absorb the light energy and convert it into chemical energy ATP and NADPH2. These products of light reaction move out from the thylakoid to the stroma of the chloroplast.

63. Who discovered Light reaction?

1. Robert Brown
2. Robert Hill
3. Robert Whitaker
4. Thomas Roe

Explanation

Light dependent photosynthesis was discovered by Robin Hill (1939). This reaction takes place in the presence of light energy in thylakoid membranes (grana) of the chloroplasts.

64. Light independent reactions are carried out in_____

1. Stomata
2. Stroma
3. Chloroplast
4. Ribosome

Explanation

The second steps (dark reaction or biosynthetic pathway) is carried out in the stroma. During this reaction CO2 is reduced into carbohydrates with the help of light generated ATP and NADPH2. This is also called as Calvin cycle and is carried out in the absence of light.

65. What is the input of Calvin cycle?

1. O2
2. CO2
3. H2O
4. COOH

Explanation

In Calvin cycle the inputs are CO2 from the atmosphere and the ATP and NADPH2 produced from light reaction.

66. When was Melvin Calvin awarded with Nobel Prize?

1. 1962
2. 1961
3. 1991
4. 1999

Explanation

Melvin Calvin, an American biochemist, discovered chemical pathway for photosynthesis. The cycle is named as Calvin cycle. He was awarded with Nobel Prize in the year 1961 for his discovery.

67. Which of the following internal factors affect Photosynthesis?

1. Accumulation of carbohydrates
2. Hormones
3. Light
4. Leaf age
5. 1, 2
6. 1, 3
7. 1, 2, 4
8. All the above

Explanation

Factors Affecting Photosynthesis:

a) Internal Factors:

i) Pigments ii) Leaf age iii) Accumulation of carbohydrates iv) Hormones

b) External Factors:

i) Light ii) Carbon dioxide iii) Temperature iv) Water v) Mineral elements

68. Who was awarded Bharat Ratna for his work in Artificial photosynthesis?

1. M.S. Swaminathan
2. C.N.R. Rao
3. Verghese Kurien
4. B.R. Ambedkar

Explanation

Artificial photosynthesis is a method for producing renewable energy by the use of sunlight. Indian scientist C.N.R. Rao who was conferred the Bharat Ratna (2013) is also working on similar technology of artificial photosynthesis to produce – Hydrogen fuel (renewable energy).

69. Which of the following statement about Mitochondria is correct?

1. Mitochondria are filamentous or granular cytoplasmic organelles present in cells.
2. The mitochondria were first discovered by Kolliker in 1857
3. Mitochondria are organelles within eukaryotic cells that produce adenosine triphosphate
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mitochondria are filamentous or granular cytoplasmic organelles present in cells. The mitochondria were first discovered by Kolliker in 1857 as granular structures in striated muscles. Mitochondria (singular: mitochondrion) are organelles within eukaryotic cells that produce adenosine triphosphate (ATP) which form the energy currency of the cell, for this reason, the mitochondria is referred to as the “Power house of the cell”.

70. Match the composition of mitochondria:

1. Protein 1. 5-7%
2. Lipids 2. 60-70%
3. RNA 3. 25-30%
4. 1, 3, 2
5. 2, 1, 3
6. 3, 2, 1
7. 2, 3, 1

Explanation

Mitochondria vary in size from 0.5 µm to 2.0 µm. Mitochondria contain 60-70% protein, 25-30% lipids, 5-7% RNA and small amount of DNA and minerals.

71. Which of the following statement about Mitochondria is correct?

1. It consists two membranes called inner and outer membrane.
2. Each membrane is 60-70A˚ thick
3. It has porin molecules (proteins) which form channels for passage of molecules through it.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mitochondrial Membranes consists two membranes called inner and outer membrane. Each membrane is 60-70A˚ thick. Outer mitochondrial membrane is smooth and freely permeable to most small molecules. It contains enzymes, proteins and lipids. It has porin molecules (proteins) which form channels for passage of molecules through it.

72. What % of proteins and lipids does Inner mitochondrial membrane has?

1. 40
2. 80
3. 99
4. 30

Explanation

Inner mitochondrial membrane is semi permeable membrane and regulates the passage of materials into and out of the mitochondria. It is rich in enzymes and carrier proteins. It consists of 80% proteins and lipids.

73. The finger like projections of inner mitochondrial membrane are called as__________

1. Stelle
2. Pith
3. Cristae
4. Stroma

Explanation

The inner mitochondrial membrane gives rise to finger like projections called cristae. These cristae increase the inner surface area (fold in inner membrane) of the mitochondria to hold variety of enzymes.

74. Which of the following statement about Oxysomes is incorrect?

1. They involve in ATP synthesis.
2. They are present in outer mitochondrial membrane
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The inner mitochondrial membrane bear minute regularly spaced tennis racket shaped particles known as oxysomes (F1particle). They involve in ATP synthesis

75. Which of the following are the functions of Mitochondria?

1. ATP factory of the cell.
2. It helps the cells to maintain normal concentration of calcium ions
3. It regulates the metabolic activity of the cell.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Functions of Mitochondria:

• Mitochondria is the main organelle of cell respiration. They produce a large number of ATP molecules. So, they are called as power houses of the cell or ATP factory of the cell.
• It helps the cells to maintain normal concentration of calcium ions.
• It regulates the metabolic activity of the cell.

76. Which of the following statement is correct?

1. Respiration involves exchange of gases between the organism and the external environment
2. Biochemical process occurs within cells where the food is oxidized to obtain energy, this is known as cellular respiration
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Respiration involves exchange of gases between the organism and the external environment. The plants obtain oxygen from their environment and release carbon dioxide and water vapour. This exchange of gases is known as external respiration. It is a physical process. Biochemical process occurs within cells where the food is oxidized to obtain energy, this is known as cellular respiration.

77. What is the by-product of Aerobic respiration?

1. Carbon dioxide
2. Water
3. Oxygen
4. ATP
5. 1, 2, 3
6. 1, 3, 4
7. 1, 2, 4
8. None

Explanation

Aerobic respiration is the type of cellular respiration in which organic food is completely oxidized with the help of oxygen into carbon dioxide, water and energy. It occurs in most plants and animals.

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

78. Breaking down of glucose into pyruvic acid is called as____

1. Glycolysis
2. Krebs Cycle
3. Calvin cycle
4. None

Explanation

Glycolysis (Glucose splitting) is the breakdown of one molecule of glucose (6 carbon) into two molecules of pyruvic acid (3 carbon). Glycolysis takes place in cytoplasm of the cell. It is the first step of both aerobic and anerobic respiration.

79. Which of the following is also known as Tricarboxylic Acid Cycle?

1. Glycolysis
2. Krebs Cycle
3. Calvin cycle
4. Photochemical cycle

Explanation

Krebs Cycle occurs in mitochondria matrix. At the end of glycolysis, 2 molecules of pyruvic acid enter into mitochondria. The oxidation of pyruvic acid into CO2 and water takes place through this cycle. It is also called Tricarboxylic Acid Cycle (TCA).

80. What is the by-product of Anaerobic respiration glucose?

1. Acetic acid
2. Formic acid
3. Lactic acid
4. Lactate

Explanation

Anaerobic respiration takes place without oxygen. Glucose is converted into ethanol (in plants) or lactate (in some bacteria)

C6H12O6 → 2CO2 + 2C2H5OH + Energy (ATP)

81. Respiratory quotient =

1. Volume of CO2 liberated/ Volume of O2 consumed
2. Volume of O2 liberated/ Volume of CO2 consumed
3. Volume of CO liberated/ Volume of O2 consumed
4. Volume of CO2 liberated Volume of H2O consumed

Explanation

Respiratory quotient is the ratio of volume of carbon dioxide liberated and the volume of oxygen consumed during respiration. It is expressed as

RQ = Volume of CO2 liberated/ Volume of O2 consumed

82. Which of the following statement about Electron Transport Chain is correct?

1. This is accomplished through a system of electron carrier complex called electron transport chain (ETC) located on the inner membrane of the mitochondria
2. NADH2 and FADH2 molecules formed during glycolysis and Krebs cycle are oxidised to NAD+ and FAD+ to release the energy via electrons
3. This is accomplished through a system of electron carrier complex called electron transport chain (ETC) located on the inner membrane of the mitochondria
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Electron Transport Chain is accomplished through a system of electron carrier complex called electron transport chain (ETC) located on the inner membrane of the mitochondria. NADH2 and FADH2 molecules formed during glycolysis and Krebs cycle are oxidised to NAD+ and FAD+ to release the energy via electrons. The electrons, as they move through the system, release energy which is trapped by ADP to synthesize ATP. This is called oxidative phosphorylation. In this process, O₂ the ultimate acceptor of electrons gets reduced to water.

10th Science Lesson 13 Questions in English

13] Structural Organisation Of Animals

1. Kingdom Animalia is divided into____ groups

1. 3
2. 2
3. 5
4. 4

Explanation

The variety in nature and habits of animals in the biosphere are quite amazing and interesting. t ‘Kingdom Animalia’ is divided into two groups, Invertebrates and Chordates.

2. Which of the following is correctly matched?

1. Invertebrate – Leech
2. Vertebrate – Rabbit
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Kingdom Animalia has a great diversity in the habit, habitat, structural organisation and mode of reproduction between the animals existing on earth. In this chapter, you will understand the structural morphology and anatomy of an Invertebrate (Leech) and a Vertebrate (Rabbit).

3. The scientific name of the Indian cattle leech is_______

1. Bos nomadicus
2. Bos elephantis
3. Hirudinaria granulosa
4. Oryctolagus cuniculus

Explanation

The scientific name of the Indian cattle leech is Hirudinaria granulosa which belongs to Phylum Annelida. Annelids are metamerically segmented worms with well-developed organ systems.

4. The scientific name of the common rabbit is____

1. Bos nomadicus
2. Bos elephantis
3. Hirudinaria granulosa
4. Oryctolagus cuniculus

Explanation

The scientific name of the common rabbit is Oryctolagus cuniculus. It represents Phylum Chordata and Class Mammalia.

5. Which of the following statement about mammals is correct?

1. Mammals occupy the highest group in the animal kingdom and show advancement over the other groups of animals
2. Mammary gland in females is the most striking feature of a mammal
3. They are cold blooded and possess covering of hair on the body
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mammals occupy the highest group in the animal kingdom and show advancement over the other groups of animals. They are warm blooded and possess covering of hair on the body. Mammary gland in females is the most striking feature of a mammal.

6. Match the Taxonomic Position of Indian Cattle Leech:

1. Phylum 1. Hirudinaria
2. Order 2. Annelida
3. Genus 3. Hirudinea
4. Class 4. Gnathobdellida
5. 1, 2, 3, 4
6. 3, 2, 1, 4
7. 2, 4, 1, 3
8. 2, 3, 1, 4

Explanation

7. Hirudinaria granulosa (Indian Cattle Leech) is found in_____

1. India
2. Pakistan
3. Sri Lanka
4. All the above

Explanation

Hirudinaria granulosa (Indian Cattle Leech) is found in India, Bangladesh, Pakistan, Myanmar and Sri Lanka. It lives in freshwater ponds, lakes, swamps and slow streams.

8. Indian Cattle Leech is______

1. Endoparasite
2. Ectoparasite
3. Omiparasite
4. None

Explanation

Hirudinaria granulosa (Indian Cattle Leech) are ectoparasitic and feed on the blood of fishes, frogs, cattle and human. It is sanguivorous (blood sucking) in nature.

9. Which of the following statement about leech is correct?

1. The body of a leech is soft, vermiform, elongated and segmented.
2. Dorsal surface is blue in colour and the ventral surface is orange yellow or orange red in colour
3. It becomes ribbon shaped when extended and almost cylindrical when contracted
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The body of a leech is soft, vermiform, elongated and segmented. It becomes ribbon shaped when extended and almost cylindrical when contracted. Leeches may grow to a length of 35cm. Dorsal surface is olive green in colour and the ventral surface is orange yellow or orange red in colour.

10. The body of leech is metamerically divided into____ segments

1. 22
2. 33
3. 19
4. 55

Explanation

Metamerism is the segmentation of the body. The body of leech is metamerically divided into 33 segments. The segments are arranged one behind the other.

11. How many pairs of eyes does leech have?

1. 10
2. 2
3. 1
4. 5

Explanation

On the dorsal side there are five pairs of eyes on the first five segments. Each segment bears a number of sensory projections called receptors.

12. A temporary clitellum is formed on which segment is meant to produce a cocoon?

1. 10 – 11
2. 9 – 11
3. 13 – 15
4. 7 – 11

Explanation

Each segment is further superficially subdivided into rings or annuli. A temporary clitellum is formed on segments 9-11, which is meant to produce a cocoon during the breeding season.

13. Which of the following statement about leech is correct?

1. Leech has two suckers
2. Posterior suckers help in attachment and locomotion.
3. The sucker located at the anterior end is called anterior sucker or oral sucker
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Leech has two suckers. The sucker located at the anterior end is called anterior sucker or oral sucker which is ventral in position occupying the first five segments. The posterior sucker is formed by the fusion of the last seven segments. The anterior sucker helps in feeding, while both the suckers help in attachment and locomotion.

14. Anus of leech opens at ____ segment

1. 12^th
2. 26^th
3. 22^nd
4. 13^th

Explanation

Mouth is located in the middle of anterior sucker. Anus is a small aperture that opens on the mid-dorsal side of 26th segment.

15. Nephridia open to the exterior by ____ pairs of nephridiopores

1. 25
2. 17
3. 29
4. 15

Explanation

Nephridia open to the exterior by 17 pairs of nephridiopores. They lie ventrally on the last annulus of each segment from 6 to 22.

16. Match the following with respective segments

1. Cephalic region 1. 27^th – 33rd
2. Clitellar region 2. 1^st – 5^th
3. Middle region 3. 9^th, 10^th and 11^th
4. Posterior sucker 4. 12^th – 22^nd
5. 2, 1, 3, 4
6. 2, 3, 4, 1
7. 3, 1, 2, 4
8. 4, 1, 2, 3

Explanation

17. Which of the following statement about body wall of leech is correct?

1. Body wall of leech includes three layers
2. Cuticle is the outermost layer
3. Dermis which lies below the epidermis formed of connective tissue
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Body wall of leech includes five layers: (i) cuticle (outermost layer) (ii) epidermis which lies below the cuticle (iii) dermis which lies below the epidermis formed of connective tissue (iv) muscular layer formed of circular and longitudinal muscles (v) botryoidal tissue lies beneath longitudinal muscles and fills the entire coelom around the gut.

18. How many types of movements take place in leech?

1. 2
2. 4
3. 5
4. 3

Explanation

Locomotion in leech takes place by two methods: (i) looping or crawling movement (ii) Swimming movement.

19. Which of the following statement is correct?

1. Looping or Crawling movement is brought about by the contraction and relaxation of muscles
2. Leeches swim very actively and perform undulating movements in water.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Looping or Crawling movement is brought about by the contraction and relaxation of muscles. The two suckers serve for attachment during movement on a substratum. Leeches swim very actively and perform undulating movements in water.

20. Mouth of leech is ______ aperture situated in the middle of the anterior sucker.

1. Biradiated
2. Triradiated
3. Monoradited
4. Pentaradiated

Explanation

The alimentary canal of leech is a straight tube running from the mouth to the anus. Mouth is a triradiate aperture situated in the middle of the anterior sucker that leads into the small buccal cavity.

21. The wall of the buccal cavity of leech bears ________ jaws with single row of minute teeth

1. 3
2. 4
3. 7
4. 2

Explanation

The wall of the buccal cavity of leech bears three jaws with single row of minute teeth. The jaws are provided with papillae which bear the openings of salivary glands. Mouth and buccal cavity occupy the first five segments.

22. Pharynx of leech leads into crop through a short and narrow_____

1. Bronchus
2. Larynx
3. Oesophagus
4. Bronchioles

Explanation

The buccal cavity leads into muscular pharynx. It is surrounded by salivary glands. The secretion of saliva contains hirudin which prevents the coagulation of blood. Pharynx leads into crop through a short and narrow oesophagus

23. Which of the following statement is correct in leech?

1. The last chamber of crop opens into stomach.
2. Crop is the largest portion of the alimentary canal.
3. The rectum opens to the exterior by anus.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Crop is the largest portion of the alimentary canal. It is divided into a series of 10 chambers. The chambers communicate with one another through circular apertures surrounded by sphincters. The last chamber of crop opens into stomach. The stomach leads into intestine which is a small straight tube that opens into rectum. The rectum opens to the exterior by anus.

24. During feeding the leech attaches itself to its victim strongly by _________ sucker

1. Anterior
2. Posterior
3. Both a and b
4. None

Explanation

The leech feeds by sucking the blood of cattle and other domestic animals. During feeding the leech attaches itself to its victim strongly by the posterior sucker.

25. In leech the blood is sucked by_____

1. Jaw
2. Pharynx
3. Larynx
4. Tongue

Explanation

The leech makes a triradiate or Y shaped incision in the skin of the host by the jaws protruded through the mouth. The blood is sucked by muscular pharynx and the salivary secretion is poured.

26. Digestion in leech takes place in stomach by the action of____ enzyme

1. Lipase
2. Proteolytic
3. Amylase
4. Pepsin

Explanation
The blood passes from the crop into the stomach. Digestion takes place in stomach by the action of proteolytic enzyme. The digested blood is then absorbed slowly by the intestine. Undigested food is stored in rectum and egested through anus.

27. Leeches prevent blood clottng by secreting a protein called_____

1. Lipase
2. Leucocyte
3. Hirudin
4. Haemoglobin

Explanation

Leeches prevent blood clotting by secreting a protein called hirudin. They also inject an anaesthetic substance that prevents the host from feeling their bite.

28. Assertion(A): Leeches can sense vibrations through their skin.

Reason(R): Leeches do not have ear

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

Leeches do not have ear, hence can sense vibrations through their skin. Leeches have 2 to 10 tiny eyes, which helps them to locate their food.

29. Leeches can suck blood ____ times more than their body weight

1. 9
2. 5
3. 10
4. 15

Explanation

Leeches can suck blood five times more than their body weight. It may take more than a year for the complete digestion and absorption of a full meal.

30. Respiration takes place through the ____ in leech

1. Nostril
2. Jaw
3. Anus
4. Skin

Explanation

Respiration takes place through the skin in leech. Dense network of tiny blood vessels called as capillaries containing the haemocoelic fluid extend in between the cells of the epidermis.

31. The exchange of respiratory gases in leech takes place by_____

1. Osmosis
2. Diffusion
3. Pressure
4. None

Explanation

The exchange of respiratory gases takes place by diffusion. Oxygen dissolved in water diffuses through the skin into haemocoelic fluid, while carbon dioxide diffuses out. The skin is kept moist and slimy due to secretion of mucus which also prevents it from drying.

32. In leech, circulation is brought about by ____ system

1. Respiratory
2. Haemocoelic
3. Haemophrage
4. None

Explanation

In leech, circulation is brought about by haemocoelic system. There are no true blood vessels. The blood vessels are replaced by channels called haemocoelic channels or canals filled with blood like fluid.

33. How many longitudinal channels are there in leech Circulatory System?

1. 6
2. 4
3. 1
4. 3

Explanation

In leech, there are four longitudinal channels. One channel lies above (dorsal) the alimentary canal, one below (ventral) the alimentary canal. The other two channels lie on either (lateral) side of the alimentary canal which serve as heart and have inner valves. All the four channels are connected together posteriorly in the 26th segment.

34. In leech, excretion takes place by segmentally arranged paired tubules called____

1. Neurodia
2. Nephridia
3. Nervodia
4. None

Explanation

In leech, excretion takes place by segmentally arranged paired tubules called nephridia. There are 17 pairs of nephridia which open out by nephridiopores from 6th to 22nd segments.

35. Which of the following statement is correct?

1. Leech is hermaphrodite
2. They have male and female reproductive organs are present in the same animal
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Leech is hermaphrodite because both the male and female reproductive organs are present in the same animal.

36. How many pair of testes are there in leech?

1. 7
2. 11
3. 13
4. 14

Explanation

There are eleven pairs of testes in leech, one pair in each segment from 12 to 22 segments. They are in the form of spherical sacs called testes sacs.

37. Which of the following are contained in Female Reproductive System of leech?

1. Ovaries
2. Oviducts
3. Epididymis
4. Vagina
5. 1, 2, 4
6. 1, 3, 4
7. 2, 3, 4
8. All the above

Explanation

Female Reproductive System consists of ovaries, oviducts and vagina. There is a single pair of ovary in the 11th segment on the ventral side. Each ovary is a coiled ribbon-shaped structure.

38. In leech, vagina which lies mid-ventrally in the posterior part of the________ segment

1. 11^th
2. 12^th
3. 19^th
4. 21^st

Explanation

The ova are budded off from the ovary. From each ovary runs a short oviduct. The oviducts of the two sides joins together, to form a common oviduct. The common oviduct opens into a pear-shaped vagina which lies mid-ventrally in the posterior part of the 11th segment.

39. Cocoon is also known as egg case which is formed around______ segments

1. 3^rd
2. 9^th
3. 10^th
4. 11^th
5. 1, 2
6. 2, 3, 4
7. 2, 3
8. 1, 3, 4

Explanation

Internal fertilization takes place. This is followed by cocoon formation. Cocoon is also known as egg case which is formed around the 9th, 10th and 11th segments.

40. How many embryos are found in cocoon?

1. 1 to 10
2. 12 to 18
3. 1 to 24
4. 15 to 25

Explanation

Development is direct and proceeds in cocoon which contain one to 24 embryos. Young leech resembling the adult emerges.

41. Which of the following statement is incorrect?

1. Leeches are effective in increasing blood circulation and breaking up blood clots
2. Biochemical substances derived from leech saliva are used for preparation of pharmaceutical drugs that can treat hypertension
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Leeches are effective in increasing blood circulation and breaking up blood clots. It is surprising that they can be used to treat cardiovascular diseases. Biochemical substances derived from leech saliva are used for preparation of pharmaceutical drugs that can treat hypertension.

42. Match the following of Rabbit correctly:

1. Phylum 1. Oryctolagus
2. Order 2. Chordata
3. Class 3. Mammalia
4. Genus 4. Lagomorpha
5. 1, 2, 3, 4
6. 2, 4, 3, 1
7. 2, 3, 1, 4
8. 2, 3, 4, 1

Explanation

43. The pygmy rabbit was listed as a threatened species in Washington in_____

1. 1991
2. 1990
3. 1970
4. 1979

Explanation

The pygmy rabbit was listed as a threatened species in Washington in 1990, because of decline in its population size and distribution due to habitat loss. In March 2003, the Columbia Basin Pygmy Rabbit was federally listed as an endangered species.

44. Which of the following statement is correct about Rabbit?

1. It has an elongated and cylindrical body
2. They grow about 45 cm in length and weigh about 2.25 kg as adult.
3. Body is covered with fur which serves to keep it warm.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Rabbit has an elongated and cylindrical body. Males and females are of the same size. They grow about 45 cm in length and weigh about 2.25 kg as adult. The colour varies from white to black and white. Body is covered with fur which serves to keep it warm.

45. Which of the following statement rabbit is correct?

1. The body of the rabbit is divisible into the head, neck, trunk and tail
2. Head is ovoid, flattened and bears a truncate snout
3. The mouth is a longitudinal slit-like bounded by upper lip and lower lip.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The body of the rabbit is divisible into the head, neck, trunk and tail. Head is ovoid, flattened and bears a truncate snout. It contains mouth, external nares, eyes, ears and vibrissae. The mouth is a transverse slit-like bounded by upper lip and lower lip. Just above the mouth are two oblique openings called nostrils. From each side of the upper lip tactile hairs or vibrissae (whiskers) project outwards.

46. The trunk of rabbit is divisible into an anterior ________ and a posterior_____

1. Thorax, Abdomen
2. Abdomen, Thorax
3. Trachea, Thorax
4. Thorax, Abdomen

Explanation

The trunk of rabbit is divisible into an anterior thorax and a posterior abdomen. In females, four or five teats or nipples are present on the ventral surface between the thorax and abdomen.

47. The trunk of rabbit bears two pairs of____ limbs

1. Pentadactyl
2. Pectadactyl
3. Hexactyl
4. Tridactyl

Explanation

The trunk of rabbit bears two pairs of pentadactyl limbs. The forelimbs are shorter than the hind limbs. All the digits bear claws.

48. The anus of the rabbit is present at the____ end of the abdomen at the base of tail

1. Anterior
2. Posterior
3. Dorsal
4. Ventral

Explanation

The anus of the rabbit is present at the posterior end of the abdomen at the base of tail. In females on the ventral side a slit like vulva is present. In males, penis is present in the ventral side of anus. The male has a pair of testes enclosed by scrotal sacs.

49. Which of the following are present in rabbit?

1. Sweat gland
2. Sebaceous gland
3. Mammary glands
4. All the above

Explanation

The integument forms the outer covering of the body. The structures of rabbit which are derived from it are hairs, claws, nails and glands like sweat glands, sebaceous glands and mammary glands.

50. Which of the following statement is correct?

1. Mammary glands are modified glands of the skin.
2. They secrete milk and help in nourishing young ones.
3. The sweat glands and sebaceous glands embedded in the skin regulate the body temperature
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mammary glands are modified glands of the skin. They secrete milk and help in nourishing young ones. The sweat glands and sebaceous glands embedded in the skin regulate the body temperature.

51. Which of the following statement is correct?

1. The body of rabbit is divisible into thoracic cavity and abdominal cavity
2. Lungs and heart lie in the thoracic cavity
3. Abdominal cavity encloses digestive and urinogenital system.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Rabbit is a coelomate animal. The body is divisible into thoracic cavity and abdominal cavity separated by transverse partition called diaphragm. Lungs and heart lie in the thoracic cavity, whereas, abdominal cavity encloses digestive and urinogenital system.

52. _____is the characteristic feature of mammals

1. Arms
2. Anus
3. Diaphragm
4. Bones

Explanation

Diaphragm is the characteristic feature of mammals. Breathing movements are brought by the movement of the diaphragm.

53. Which of the following is not included in alimentary canal?

1. Pharynx
2. Oesophagus
3. Larynx
4. Caecum

Explanation

The digestive system includes the alimentary canal and the associated digestive glands. The alimentary canal consists of mouth, buccal cavity, pharynx, oesophagus, stomach, small intestine, caecum, large intestine and anus.

54. Which of the following statement is correct?

1. Mouth is a longitudinal slit bounded by upper and lower lips
2. The floor of the buccal cavity is occupied by a muscular tongue.
3. Jaws bear teeth.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mouth is a transverse slit bounded by upper and lower lips. It leads into the buccal cavity. The floor of the buccal cavity is occupied by a muscular tongue. Jaws bear teeth.

55. In rabbit, Oesophagus opens into the stomach followed by_____

1. Large intestine
2. Caecum
3. Anus
4. Small intestine

Explanation

Oesophagus opens into the stomach followed by small intestine. Caecum is a thin-walled sac present at the junction of small intestine and large intestine. It contains bacteria that helps in digestion of cellulose. The small intestine opens into the large intestine which has colon and rectum. The rectum finally opens outside by the anus.

56. Which of the following glands are included in digestive glands?

1. Liver
2. Pancreas
3. Salivary glands
4. All the above

Explanation

The digestive glands are salivary glands, gastric glands, liver, pancreas and intestinal glands. The secretions of digestive glands help in digestion of food in the alimentary canal.

57. Which of the following statement is correct?

1. Teeth are hard bone-like structures used to cut, tear and grind the food materials
2. The existence of two sets of teeth in the life of an animal is called diphyodont dentition
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Teeth are hard bone-like structures used to cut, tear and grind the food materials. The rabbit has two sets of teeth. The existence of two sets of teeth in the life of an animal is called diphyodont dentition. The two types of teeth are milk teeth (young ones) and permanent teeth (in adults).

58. How many kinds of teeth are there in mammal?

1. 3
2. 4
3. 6
4. 2

Explanation

In rabbit the teeth are of different types. Hence, the dentition is called heterodont. There are four kinds of teeth in mammals viz. the incisors (I), canines (C), premolars (PM) and molars (M). This is expressed in the form of a dental formula.

59. The gap between the incisors and premolar is called_______

1. Precisors
2. Molars
3. Canines
4. Diastema

Explanation

Canines are absent in rabbit. The gap between the incisors and premolar is called diastema. It helps in mastication and chewing of food in herbivorous animals.

60. Which of the following statement is correct?

1. Respiration takes place by a pair of lungs, which are light spongy tissues enclosed in the thoracic cavity
2. On the lower side of the thoracic cavity is the dome shaped diaphragm.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Respiration takes place by a pair of lungs, which are light spongy tissues enclosed in the thoracic cavity. The thoracic cavity is bound dorsally by the vertebral column and ventrally by the sternum, laterally by the ribs. On the lower side of the thoracic cavity is the dome shaped diaphragm.

61. Each lung is enclosed by a double membranous_____

1. Alveoli
2. Pleura
3. Neuron
4. None

Explanation

Each lung is enclosed by a double membranous pleura. Atmospheric air passes through the external nostril and nasal passages into the pharynx.

62. _____ is known as voice box

1. Pharynx
2. Larynx
3. Trachea
4. Buccal cavity

Explanation

The anterior part of the wind pipe is enlarged to form the larynx or voice box with its wall supported by four cartilaginous plates. Inside the larynx lies the vocal cord and its vibrations result in the production of sound. The larynx leads into trachea or wind pipe.

63. ____ prevents the entry of food into the trachea through the glottis

1. Larynx
2. Trachea
3. Bronchi
4. Epiglottis

Explanation

Tracheal walls are supported by rings of cartilage which help in the free passage of air. The epiglottis prevents the entry of food into the trachea through the glottis.

64. Inspiration is an _________ process

1. Active
2. Passive
3. Both a and b
4. None

Explanation

The respiratory events consist of inspiration (breathing in) and expiration (breathing out) allowing exchange of gases (oxygen and carbon dioxide). Inspiration is an active process while expiration is a passive process.

65. The heart is pear shaped and lies in the thoracic cavity in between_____

1. Kidneys
2. Lungs
3. Pancreas
4. None

Explanation

The circulatory system is formed of blood, blood vessels and heart. The heart is pear shaped and lies in the thoracic cavity in between the lungs. It is enclosed by pericardium, a double layered membrane.

66. The heart of rabbit is _______ chambered

1. Three
2. Four
3. Two
4. Five

Explanation

The heart of rabbit is four chambered with two auricles and two ventricles. The right and left auricles are separated by inter-auricular septum, similarly right and left ventricles are separated by interventricular septum.

67. The right auricle opens into the right ventricle by right auriculoventricular aperture, guarded by_________

1. Bicuspid valve
2. Tricuspid valve
3. Pentacuspid valve
4. Monocuspid valve

Explanation

The right auricle opens into the right ventricle by right auriculoventricular aperture, guarded by a tricuspid valve. The left auricle opens into the left ventricle by left auriculoventricular aperture guarded by a bicuspid valve or mitral valve.

68. The right auricle receives deoxygenated blood through_____

1. Arteries
2. Veins
3. Both a and b
4. None

Explanation

The right auricle receives deoxygenated blood through two precaval (superior vena cava) and one post-caval (inferior vena cava) veins from all parts of the body. The left auricle receives oxygenated blood from the pulmonary veins from the lungs.

69. ______ carries the deoxygenated blood to the lungs

1. Aorta
2. Pulmonary trunk
3. Superior vena cava
4. Inferior vena cava

Explanation

From the right ventricle arises pulmonary trunk which carries the deoxygenated blood to the lungs and from the left ventricle arises the systemic arch (aorta) which supplies oxygenated blood to all parts of the body.

70. PNS is formed of____ pairs of cranial nerves

1. 37
2. 12
3. 18
4. 24

Explanation

The nervous system in rabbit is formed of the central nervous system (CNS), peripheral nervous system (PNS) and autonomic nervous system (ANS). CNS consists of brain and spinal cord. PNS is formed of 12 pairs of cranial nerves and 37 pairs of spinal nerves. ANS comprises sympathetic and parasympathetic nerves

71. Brain is situated in the cranial cavity and covered by_____ membranes

1. 3
2. 5
3. 2
4. 6

Explanation

Brain is situated in the cranial cavity and covered by three membranes called an outer duramater, an inner piamater and a middle arachnoid membrane.

72. Match the following

1. Forebrain 1. rhombencephalon
2. Midbrain 2. prosencephalon
3. Hindbrain 3. Mesencephalon
4. 2, 3, 1
5. 1, 2, 3
6. 3, 1, 2
7. 1, 3, 2

Explanation

The brain is divided into forebrain (prosencephalon), midbrain (mesencephalon) and hindbrain (rhombencephalon).

73. ______ consists of a pair of olfactory lobes, cerebral hemispheres and diencephalon

1. Forebrain
2. Midbrain
3. Hindbrain
4. All the above

Explanation

Forebrain consists of a pair of olfactory lobes, cerebral hemispheres and diencephalon. The right and left cerebral hemispheres are connected by transverse band of nerve tissue called corpus callosum.

74. _____ includes the optic lobes.

1. Forebrain
2. Midbrain
3. Hindbrain
4. All the above

Explanation

The midbrain includes the optic lobes. The hindbrain consists of the cerebellum, pons varolii and medulla oblongata. You will study about the details of mammalian brain in the chapter on nervous system.

75. Each kidney is made of several_____

1. Alveoli
2. Neurons
3. Nephrons
4. None

Explanation

Each kidney is made of several nephrons. It separates the nitrogenous wastes from blood and excretes it in the form of urea.

76. What is the colour of kidney in rabbit?

1. Red
2. Pale red
3. Dark red
4. Brown

Explanation

Kidneys in rabbit are dark red, bean shaped organs situated in the abdominal cavity. From each kidney arises the ureters which open posteriorly into the urinary bladder and leads into a thick-walled muscular duct called urethra.

77. Which of the following statement is correct?

1. Sexual dimorphism is exhibited in rabbits.
2. The male and female sexes are separate and are morphologically different.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Sexual dimorphism is exhibited in rabbits. The male and female sexes are separate and are morphologically different.

78. How many accessary glands are there in male rabbit?

1. 2
2. 4
3. 3
4. 5

Explanation

There are three accessory glands in male rabbit namely prostate gland, cowper’s gland and perineal gland. Their secretions are involved in reproduction

79. The anterior part of the oviduct is________

1. Vestibule
2. Vagina
3. Uterus
4. Vulva

Explanation

The anterior part of the oviduct is the fallopian tube. It leads into a wider tube called the uterus. The uterus join together to form a median tube called vagina. The common tube is formed by the union of urinary bladder and the vagina and is called the urinogenital canal or vestibule

80. How many pair of accessory glands are there in female rabbit?

1. 2
2. 5
3. 4
4. 3

Explanation

A pair of Cowper’s gland and perineal gland are the accessory glands present in the female reproductive system. The female reproductive system of rabbit consists of a pair of ovaries which are small ovoid structures.

10th Science Lesson 14 Questions in English

14] Transportation In Plants And Circulation In Animals

1. Which of the following statement is correct?

1. Multicellular organisms possess millions of cells in their body
2. Every cell needs a constant supply of essential substances like nutrients and oxygen to maintain life and survival
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Multicellular organisms possess millions of cells in their body. Every cell needs a constant supply of essential substances like nutrients and oxygen to maintain life and survival.

2. Every cell gets its energy by the breakdown of____

1. Fats
2. Minerals
3. Vitamins
4. Glucose

Explanation

Food is the only source of energy and every cell gets its energy by the breakdown of glucose. The cells utilise this energy and govern various vital activities of life.

3. Water and mineral salts absorbed by the roots reach all parts of the plant through______

1. Phloem
2. Xylem
3. Both a and b
4. None

Explanation

Water absorbed by the roots have to reach entire plant and the food synthesised by the leaves have to be distributed to all the parts of the plant. Water and mineral salts absorbed by the roots reach all parts of the plant through the xylem

4. The bulk movement of substances through the vascular tissue is called ______

1. Transportation
2. Translocation
3. Transplantation
4. None

Explanation

The food synthesised by the leaves are translocated to all parts of the plant through the phloem. The bulk movement of substances through the vascular tissue is called Translocation.

5. Which of the following are transported by Circulatory system?

1. Salts
2. Hormones
3. Oxygen
4. All the above

Explanation

In larger organisms, transport of nutrients, salts, oxygen, hormones and waste products around the body are performed by the ‘Circulatory system’

6. Which of the following are included in circulatory system?

1. Blood
2. Lymph
3. Heart
4. Blood vessels
5. 1, 2, 4
6. 2, 3, 4
7. 1, 2, 3
8. All the above

Explanation

The circulatory system consists of the circulating fluids, the blood and lymph and the heart and blood vessels which form the collecting and transporting system.

7. Which of the following statement is correct?

1. The movement of molecules from a region of higher concentration to a region of their lower concentration without the utilization of energy is called diffusion
2. It is an active process
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Th e movement of molecules in liquid and solids from a region of higher concentration to a region of their lower concentration without the utilization of energy is called diffusion. This is a passive process.

8. Active transport is carried out by membrane bound________

1. Carbohydrates
2. Proteins
3. Minerals
4. Salts

Explanation

Active transport utilizes energy to pump molecules against a concentration gradient. Active transport is carried out by membrane bound proteins.

9. Transport substances from a low concentration to a high concentration is called as_____ transport

1. Uphill
2. Downhill
3. Both a and b
4. None

Explanation

Proteins use energy to carry substances across the cell membrane hence they are oft en referred to as pumps. These pumps can transport substances from a low concentration to a high concentration (‘uphill’ transport)

10. Which of the following statement is correct?

1. Osmosis is the movement of solvent or water molecules from the region of higher concentration to the region of lower concentrate
2. This process is carried out till an equilibrium is reached
3. It is active process
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Osmosis is the movement of solvent or water molecules from the region of higher concentration to the region of lower concentration through a semi-permeable membrane. This process is carried out till an equilibrium is reached. Osmosis is the passive movement of water or any other solvent molecules.

11. ______ is a type of diffusion in which a solid absorbs water and gets swelled up

1. Imbibition
2. Plasmolysis
3. Diffusion
4. None

Explanation

Imbibition is a type of diffusion in which a solid absorbs water and gets swelled up. eg. absorption of water by seeds and dry grapes. If it were not for imbibition, seedlings would not have been able to emerge out of the soil.

12. Which of the following characteristics of root hairs are correct?

1. Thin walled
2. Slender extension of epidermal cells
3. 1 alone
4. 2 alone
5. Both 1 and 2
6. None

Explanation

There are millions of root hairs on the tip of the root which absorb water and minerals by diffusion. Root hairs are thin walled, slender extension of epidermal cell that increase the surface area of absorption.

13. Which of the following statement is correct?

1. Once the water enters the root hairs, the concentration of water molecules in the root hair cells become more than that of the cortex
2. Water from the root hair moves to the cortical cells by diffusion and then reaches the xylem
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Once the water enters the root hairs, the concentration of water molecules in the root hair cells become more than that of the cortex. Thus, water from the root hair moves to the cortical cells by osmosis and then reaches the xylem. From there the water is transported to the stem and leaves.

14. How many distinct pathways are there for water from root hairs to move deeper into root layers?

1. 3
2. 2
3. 5
4. 4

Explanation

Water is absorbed along with minerals, by the root hairs, purely by diffusion. Once water is absorbed by the root hairs, it can move deeper into root layers by two distinct pathways:

• Apoplast pathway
• Symplast pathway

15. Which of the following statement is correct?

1. The apoplastic movement of water occurs exclusively through the intercellular spaces and the walls of the cells
2. This movement does not dependent on the gradient
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The apoplastic movement of water occurs exclusively through the intercellular spaces and the walls of the cells. Apoplastic movement does not involve crossing the cell membrane. This movement is dependent on the gradient.

16. Which of the following statement is correct?

1. In symplastic movement, the water travels through the cells i.e. their cytoplasm; intercellular movement is through the plasmodesmata
2. Water enters the cells through the cell membrane, hence the movement is relatively slower
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

In symplastic movement, the water travels through the cells i.e. their cytoplasm; intercellular movement is through the plasmodesmata. Water enter the cells through the cell membrane, hence the movement is relatively slower. Movement is again down a potential gradient.

17. Transpiration is the evaporation of water in plants through_____ in the leaves

1. Chloroplast
2. Stomata
3. Mitochondria
4. Guard cells

Explanation

Transpiration is the evaporation of water in plants through stomata in the leaves. Stomata are open in the day and closed at night.

18. Which of the following statement is correct?

1. The opening and closing of the stomata is due to the change in turgidity of the guard cells.
2. When turgidity increases within the two guard cells the stoma closes
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The opening and closing of the stomata is due to the change in turgidity of the guard cells. When turgidity increases within the two guard cells the stoma open. When the guard cells lose water, it becomes flaccid and the stoma closes.

19. Water evaporates from_______ cells of leaves through the open stomata

1. Epidermal
2. Mesophyll
3. Echinodermal
4. None

Explanation

Water evaporates from mesophyll cells of leaves through the open stomata, this lowers water concentration in mesophyll cells.

20. Assertion(A): As water is lost from the leaves, pressure is created at the top to pull more water

from the xylem to the mesophyll cells

Reason(R): Transpiration pull extends up to the roots causing the roots to absorb more water

from the soil to ensure continuous flow of water from the roots to the leaves.

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

As a result of water loss through stomata, more water is drawn into these cells from the xylem present in the veins through the process of osmosis. As water is lost from the leaves, pressure is created at the top to pull more water from the xylem to the mesophyll cells, this process is called transpiration pull. This extends up to the roots causing the roots to absorb more water from the soil to ensure continuous flow of water from the roots to the leaves.

21. Which following affects Transpiration?

1. Humidity
2. Light
3. Wind speed
4. Temperature
5. 1, 2, 3
6. 1, 3, 4
7. 1, 2, 4
8. All the above

Explanation

Transpiration is affected by several external factors such as temperature, light, humidity, and wind speed. Internal factors that affect transpiration include number and distribution of stomata, percentage of open stomata, water status of the plant, canopy structure etc.

22. Which of the following are the importance of Transpiration?

1. Creates transpirational pull for transport of water
2. Cools the surface of the leaves by evaporation.
3. Supplies water for photosynthesis
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Importance of Transpiration:

• Creates transpirational pull for transport of water
• Supplies water for photosynthesis
• Transports minerals from soil to all parts of the plant
• Cools the surface of the leaves by evaporation
• Keeps the cells turgid; hence, maintains their shape

23. Assertion(A): Root pressure is responsible for pushing water to smaller height of the stem

Reason(R): As ion from the soil are actively transported into the vascular tissue of the root,

water moves along and increases the pressure inside the xylem

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

As ion from the soil are actively transported into the vascular tissue of the root, water moves along and increases the pressure inside the xylem. This pressure is called root pressure and is responsible for pushing water to smaller height of the stem.

24. Which of the following statement is correct?

1. Plants depend on minerals from soil for its nutritional requirements.
2. All minerals cannot be passively absorbed by the roots
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Plants depend on minerals from soil for its nutritional requirements. All minerals cannot be passively absorbed by the roots.

25. Which of the following statement is correct?

1. The concentration of minerals in the soil is usually lower than the concentration of minerals in the root.
2. Most minerals enter the root by active absorption through the cytoplasm of epidermal cells.
3. Minerals are present in the soil as charged particles (ions) that cannot move across cell membranes
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Two factors account for this:

• minerals are present in the soil as charged particles (ions) that cannot move across cell membranes and
• The concentration of minerals in the soil is usually lower than the concentration of minerals in the root.

Therefore, most minerals enter the root by active absorption through the cytoplasm of epidermal cells. This needs energy in the form of ATP. Then it is transported to all parts by transpiration pull.

26. Remobilising of minerals from older dying leaves to younger leaves can be seen in____

1. Deciduous plants
2. Tropical evergreen trees
3. Temperate trees
4. All the above

Explanation

Minerals are remobilised from older dying leaves to younger leaves. This phenomenon can be seen in deciduous plants.

27. Which of the following minerals are not remobilised?

1. Phosphorous
2. Calcium
3. Sulphur
4. Nitrogen

Explanation

Elements like phosphorus, sulphur, nitrogen and potassium are easily mobilised, while elements like calcium are not remobilised. Small amounts of material exchange takes place between xylem and phloem.

28. Which of the following statement is correct?

1. The food synthesised by the leaves are transported by the phloem either to the area of requirement or stored
2. Phloem tissue is composed of sieve tubes which have sieve plates
3. Cytoplasmic strands pass through the pores in the sieve plates.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The food synthesised by the leaves are transported by the phloem either to the area of requirement or stored. Phloem tissue is composed of sieve tubes which have sieve plates. Cytoplasmic strands pass through the pores in the sieve plates.

29. _____ transports food (sucrose) from a source to a sink

1. Xylem
2. Phloem
3. Both a and b
4. None

Explanation

Phloem transports food (sucrose) from a source to a sink. The source is part of the plant that synthesize food, i.e., the leaf, and sink, is the part that needs or stores the food. But, the source and sink may be reversed depending on the season, or the plant’s need.

30. Movement in xylem is always____

1. Bidirectional
2. Unidirectional
3. Tri-directional
4. None

Explanation

Since the source-sink relationship is variable, the direction of movement in the phloem can be upwards or downwards, i.e., bidirectional. In contrast, the movement is always unidirectional in xylem i.e., upwards.

31. Which of the following statement is incorrect?

1. The mechanism of translocation of sugars from source to sink is through pressure flow hypothesis
2. Glucose prepared at source (by photosynthesis) is converted to sucrose.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The mechanism of translocation of sugars from source to sink is through pressure flow hypothesis Glucose prepared at source (by photosynthesis) is converted to sucrose.

32. Sucrose moves into the companion cells, then into the living phloem sieve tube cells by___

1. Active transport
2. Passive transport
3. Both a and b
4. None

Explanation

Sucrose moves into the companion cells, then into the living phloem sieve tube cells by active transport. This process produces a hypertonic condition in the phloem.

33. Water in the adjacent xylem moves into the phloem by_____

1. Diffusion
2. Translocation
3. Osmosis
4. Peristatic waves

Explanation

Water in the adjacent xylem moves into the phloem by osmosis. As osmotic pressure builds up, the phloem sap moves to areas of lower pressure. By active transport sucrose moves into the cells where it is utilised or stored. As sugars are removed, the osmotic pressure decreases and water moves out of the phloem.

34. Which of the following statement is correct?

1. The upward movement of water and minerals from roots to different plant parts is called ascent of sap
2. A number of factors play a role in ascent of sap
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The upward movement of water and minerals from roots to different plant parts is called ascent of sap. A number of factors play a role in ascent of sap and it takes places in following steps.

35. Which of the following statement is correct?

1. Water from soil enters the root hairs due to osmosis
2. Root pressure is responsible for movement of water up to the base of the stem
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Root Pressure: Water from soil enters the root hairs due to osmosis. Root pressure is responsible for movement of water up to the base of the stem.

36. Water or any liquid rises in a capillary tube because of_____ forces

1. Chemical
2. Physical
3. Biological
4. None

Explanation

Water or any liquid rises in a capillary tube because of physical forces, this phenomenon is called capillary action. In the same way, in stem water rises up to certain height because of capillary action.

37. Water molecules form a continuous column in the xylem because of forces of______ forces

1. Adhesive
2. Cohesive
3. Both a and b
4. None

Explanation

Water molecules form a continuous column in the xylem because of forces of adhesion and cohesion among the molecules.

38. The force of attraction between molecules of water is called_____

1. Cohesion
2. Adhesion
3. Both a and b
4. None

Explanation

The force of attraction between molecules of water is called cohesion. The force of attraction between molecules of different substances is called adhesion.

39. Water molecules stick to a xylem because of force of______

1. Cohesion
2. Adhesion
3. Both a and b
4. None

Explanation

The force of attraction between molecules of different substances is called adhesion. Water molecules stick to a xylem because of force of adhesion.

40. Assertion(A): Dews are water droplets on the leaves of grass seen in the early mornings, when the climate is humid and excess of water in the soil

Reason(R): This is due to root pressure and this phenomenon is called Guttation

1. Both (A) and (R) are correct, but (R) does not explain (A)
2. Both (A) and (R) are wrong
3. Both (A) and (R) are correct and (R) explains (A)
4. (A) is Correct and (R) is wrong

Explanation

Dews are water droplets on the leaves of grass seen in the early mornings, when the climate is humid and excess of water in the soil. This is due to root pressure and this phenomenon is called Guttation which takes place through specialized cells called Hydathodes.

41. Which of the following statement is incorrect?

1. Transpiration through stomata creates vacuum which creates a suction. called transpiration pull.
2. The transpiration pull sucks the water column from the xylem tubes and thus water is able to rise to great heights even in the tallest plants.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Transpiration through stomata creates vacuum which creates a suction. called transpiration pull. The transpiration pull sucks the water column from the xylem tubes and thus water is able to rise to great heights even in the tallest plants.

42. The blood consists of____ main components.

1. 2
2. 4
3. 3
4. 1

Explanation

Blood is the main circulatory medium in the human body. It is a red coloured fluid connective tissue. The blood consists of two main components. The fluid plasma and the formed elements (blood cells) which are found suspended in the plasma.

43. Plasma is slightly_____

1. Acidic
2. Alkaline
3. Both a and b
4. None

Explanation

Plasma is slightly alkaline, non-living intercellular substance which constitutes about 55% of the blood.

44. Which of the following are present in plasma?

1. Minerals
2. Proteins
3. Hormones
4. All the above

Explanation

Organic substances like proteins, glucose, urea, enzymes, hormones, vitamins and minerals are present in the plasma.

45. What is the other name of Blood platelets?

1. Erythrocytes
2. Leucocytes
3. Thrombocytes
4. All the above

Explanation

Blood corpuscles are of three types:

1. Red blood corpuscles (RBC) or Erythrocytes

2. White blood corpuscles (WBC) or Leucocytes

3. Blood platelets or Thrombocytes

46. _____ are the most abundant cells in the human body

1. RBC
2. WBC
3. Blood platelets
4. Nephrons

Explanation

Red blood corpuscles (Erythrocytes) are the most abundant cells in the human body. RBC’s are formed in the bone marrow.

47. Which of the following statement is correct?

1. The RBC’s impart red colour to the blood due to presence of respiratory pigment haemoglobin.
2. Their life span is about 180 days.
3. Matured mammalian RBC’s do not have cell organelles and nucleus.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The RBC’s impart red colour to the blood due to presence of respiratory pigment haemoglobin. Matured mammalian RBC’s do not have cell organelles and nucleus. They are biconcave and disc-shaped. Their life span is about 120 days. RBC is involved in the transport of oxygen from lungs to tissues.

48. Which of the following statement is correct?

1. Mammalian RBC lack nucleus and makes the cells biconcave and increase surface area for oxygen binding
2. Loss of mitochondria allows the RBC to transport all the oxygen to tissues
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Mammalian RBC lack nucleus and makes the cells biconcave and increase surface area for oxygen binding, loss of mitochondria allows the RBC to transport all the oxygen to tissues, and loss of endoplasmic reticulum allows more flexibility for RBC to move through the narrow capillaries.

49. In which of the following WBC are found?

1. Spleen
2. Bone marrow
3. Thymus
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

WBC are colourless. They do not have haemoglobin and are nucleated cells. It is found in the bone marrow, spleen, thymus and lymph nodes.

50. The white blood corpuscles can be grouped into___ categories

1. 3
2. 2
3. 4
4. 5

Explanation

White blood corpuscles (Leucocytes) are capable of amoeboid movement. White blood corpuscles can be grouped into two categories:

• Granulocytes
• Agranulocytes

51. Which of the following statement about Granulocytes?

1. They contain granules in their cytoplasm.
2. Their nucleus is irregular or lobed
3. The granulocytes are of two types
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Granulocytes contain granules in their cytoplasm. Their nucleus is irregular or lobed. The granulocytes are of three types:

• Neutrophils
• Eosinophils
• Basophils

52. Neutrophils are large in size and have a____ lobed nucleus

1. 3 to 4
2. 2 to 7
3. 1 to 4
4. 5 to 10

Explanation

Neutrophils are large in size and have a 2 – 7 lobed nucleus. These corpuscles form 60% – 65% of the total leucocytes. Their numbers are increased during infection and inflammation.

53. Eosinophils has a bilobed nucleus and constitute___% -___% of the total leucocytes.

1. 4 to 8
2. 2 to 3
3. 3 to 4
4. 5 to 10

Explanation

Eosinophils has a bilobed nucleus and constitute 2% – 3% of the total leucocytes. Their number increases during conditions of allergy and parasitic infections. It brings about detoxification of toxins.

54. ______ release chemicals during the process of inflammation

1. Basophils
2. Eosinophils
3. Neutrophils
4. All the above

Explanation

Basophils have lobed nucleus. They form 0.5-1.0% of the total leucocytes. They release chemicals during the process of inflammation.

55. How many types of Agranulocytes are there?

1. 3
2. 2
3. 4
4. 5

Explanation

Granules are not found in the cytoplasm of these cells. The agranulocytes are of two types: (i) Lymphocytes (ii) Monocytes

56. Lymphocytes are about____ % of the total leucocytes

1. 20 to 30
2. 30 to 40
3. 35 to 45
4. 20 to 25

Explanation

Lymphocytes are about 20-25% of the total leucocytes. They produce antibodies during bacterial and viral infections.

57. ______ are phagocytic and can engulf bacteria

1. Lymphocyte
2. Monocyte
3. Basophils
4. Neutrophils

Explanation

Monocytes are the largest of the leucocytes and are amoeboid in shape. These cells form 5 – 6 % of the total leucocytes. They are phagocytic and can engulf bacteria

58. Which of the following statement about blood platelets is correct?

1. These are small and colourless
2. There are about 2,50,000 – 4,00,000 platelets / cubic mm of blood
3. Life span of platelets in only 2–3 weeks
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Blood Platelets or Thrombocytes are small and colourless. They do not have nucleus. There are about 2,50,000 – 4,00,000 platelets / cubic mm of blood. Life span of platelets in only 2–3 days. They play an important role in clotting of blood. Platelets form clot at the site of injury and prevent blood loss.

59. Match the following

1. Anemia 1. Decrease in the number of thrombocytes
2. Leucocytosis 2. Decrease in number of erythrocytes
3. Leukopenia 3. Decrease in number of leukocytes
4. Thrombocytopenia 4. Increase in the number of leukocytes
5. 2, 1, 3, 4
6. 2, 4, 3, 1
7. 3, 1, 2, 4
8. 2, 3, 4, 1

Explanation

Anemia: Decrease in number of erythrocytes.

Leucocytosis: Increase in the number of leukocytes.

Leukopenia: Decrease in number of leukocytes.

Thrombocytopenia: Decrease in the number of thrombocytes.

60. Which of the following are the functions of blood?

1. Transport of respiratory gases (Oxygen and CO2)
2. Transport of digested food materials to the different body cells
3. Transport of hormones
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Functions of blood:

• Transport of respiratory gases (Oxygen and CO2)
• Transport of digested food materials to the different body cells
• Transport of hormones.
• It acts as buffer and also helps in regulation of pH and body temperature.
• It maintains proper water balance in the body

61. How many types of blood vessels are there?

1. 2
2. 4
3. 3
4. 5

Explanation

Blood vessels are a network of branched tubes that transport blood. There are three types of blood vessels namely arteries, veins and capillaries.

62. Which of the following statement about Arteries is correct?

1. They are thick and elastic vessels that carry blood away from the heart to various organs of the body
2. All arteries carry oxygenated blood except the pulmonary artery which carry deoxygenated blood to the lungs
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Arteries are thick and elastic vessels that carry blood away from the heart to various organs of the body. All arteries carry oxygenated blood except the pulmonary artery which carry deoxygenated blood to the lungs.

63. Which of the following statement is correct?

1. Veins are thick and non-elastic vessels that transport blood to the heart from the different organs.
2. All veins carry deoxygenated blood except the pulmonary vein which carry oxygenated blood from the lungs to the heart
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Veins are thin and non-elastic vessels that transport blood to the heart from the different organs. All veins carry deoxygenated blood except the pulmonary vein which carry oxygenated blood from the lungs to the heart

64. Which of the following statement about Capillaries is correct?

1. Capillaries are narrow tubes formed by branching of arterioles which then unite to form the venules and veins
2. They are about 8 µm in diameter
3. Capillaries are formed of single layer of leydig cells
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Capillaries are narrow tubes formed by branching of arterioles which then unite to form the venules and veins. They are about 8 µm in diameter. Capillaries are formed of single layer of endothelial cells.

65. Which of the following have open type Circulatory System?

1. Arthropods
2. Ascidians
3. Vertebrates
4. Molluscs
5. 1, 2, 3
6. 1, 2, 4
7. 2, 3, 4
8. All the above

Explanation

In open type the blood is pumped by heart into blood vessels that open into blood spaces called as sinuses. These sinuses are the body cavities which are called haemocoel. Capillary system is absent. e.g. Arthropods, Molluscs and Ascidians

66. Which of the following statement about closed type system is correct?

1. In closed type the blood flows in a complete circuit around the body through specific blood vessels
2. The blood flows from arteries to veins through small blood vessels called capillaries
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

In closed type the blood flows in a complete circuit around the body through specific blood vessels. The blood flows from arteries to veins through small blood vessels called capillaries. e.g Vertebrates.

67. Closed circulatory system was discovered by_____

1. Theocratus
2. Darwin
3. William Harvey
4. Thomas Harvey

Explanation

Closed circulatory system was discovered by William Harvey (1628) who is regarded the Father of Modern Physiology

68. Which of the following statement about heart is correct?

1. Heart is a muscular pumping organ that pumps out the blood into the blood vessels.
2. Human heart is situated between the lungs, slightly tilted toward the left and above the diaphragm in the thoracic cavity.
3. The heart is made of specialized type of muscle called the cardiac muscle.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Heart is a muscular pumping organ that pumps out the blood into the blood vessels. Human heart is situated between the lungs, slightly tilted toward the left and above the diaphragm in the thoracic cavity. The heart is made of specialized type of muscle called the cardiac muscle.

69. _____ fluid which reduces friction during heart beat and protects it from mechanical injuries

1. Cardiovascular
2. Pericardium
3. Cardium
4. None

Explanation

The heart is enclosed in a double walled sac called pericardium. It contains lubricating pericardial fluid which reduces friction during heart beat and protects it from mechanical injuries.

70. The human heart is____ chambered

1. 1
2. 2
3. 4
4. 3

Explanation

The human heart is four chambered. The two upper thin-walled chambers of the heart are called auricle or atria (sing: atrium) and two lower thick walled chambers are called ventricles.

71. The heart chambers are separated by partition called____

1. Pectum
2. Septum
3. Septa
4. Centa

Explanation

The chambers are separated by partition called septum. The septum between auricles and ventricles prevents the mixing of oxygenated and deoxygenated blood.

72. Which of the following statement is correct?

1. The two auricles are separated from each other by interatrial septum
2. The left atrium is larger than the right atrium
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The two auricles are separated from each other by interatrial septum. The left atrium is smaller than the right atrium.

73. The right atrium receives deoxygenated blood from different parts of the body through_____

1. Superior vena cava
2. Pulmonary veins
3. Inferior vena cava
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The right atrium receives deoxygenated blood from different parts of the body through the main veins superior vena cava, inferior vena cava and coronary sinus.

74. ______bring oxygenated blood to the left atrium from the lungs

1. Pulmonary veins
2. Pulmonary artery
3. Superior vena cava
4. Inferior vena cava

Explanation

Pulmonary veins bring oxygenated blood to the left atrium from the lungs. The right and left auricles pump blood into the right and left ventricles respectively.

75. Which of the following statement is correct?

1. The ventricles form the upper part of the heart.
2. The two ventricles are separated from each other by an interventricular septum
3. The left and right ventricles have thick walls because the ventricles have to pump out blood with force away from the heart
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The ventricles form the lower part of the heart. The two ventricles are separated from each other by an interventricular septum. The left and right ventricles have thick walls because the ventricles have to pump out blood with force away from the heart.

76. Which of the following statement is correct?

1. The right ventricle gives rise to aorta
2. From the right ventricle arises the pulmonary trunk which bifurcates to form right and left pulmonary arteries
3. The right and left pulmonary arteries supply deoxygenated blood to the lungs of the respective side.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

From the right ventricle arises the pulmonary trunk which bifurcates to form right and left pulmonary arteries. The right and left pulmonary arteries supply deoxygenated blood to the lungs of the respective side. The left ventricle is longer and narrower than the right ventricle. The walls are about three times thicker than the right ventricle. The left ventricle gives rise to aorta. The oxygenated blood is supplied by the aorta to various organs of the body. The coronary arteries supply blood to the heart.

77. How many types of valve are there in heart?

1. 2
2. 3
3. 4
4. 5

Explanation

The valves are the muscular flaps that regulate the flow of blood in a single direction and prevent back flow of blood. The heart contains three types of valves.

78. Right atrioventricular valve is located between_______

1. Right ventricle
2. Left ventricle
3. Right auricle
4. Left auricle
5. 1, 2
6. 1, 3
7. 2, 3
8. 3, 4

Explanation

Right atrioventricular valve is located between the right auricle and right ventricle. It has three thin triangular leaf like flaps and therefore called tricuspid valve. The apices of the flaps are held in position by chordae tendinae arising from the muscular projection of the ventricle wall known as papillary muscles.

79. Left atrioventricular valve is also known as_____ valve

1. Tricuspid
2. Bicuspid
3. Mitral
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Left atrioventricular valve is located between the left auricle and left ventricle. It has two cusps and therefore called bicuspid or mitral valve

80. Match the following

1. Two chambered 1. Aves
2. Three chambered 2. Fishes
3. Four chambered 3. Amphibians
4. Incomplete four chambered 4. Reptiles
5. 2, 3, 1, 4
6. 2, 1, 3, 4
7. 1, 2, 3, 4
8. 4, 2, 1, 3

Explanation

81. The major arteries (pulmonary artery and aorta) which leave the heart have____ to prevent

backward flow.

1. Tricuspid
2. Bicuspid
3. Semilunar
4. Mitral

Explanation

The major arteries (pulmonary artery and aorta) which leave the heart have semilunar valves which prevent backward flow of blood into the ventricles. They are the pulmonary and aortic semilunar valves.

82. _______ carries oxygenated blood to all the organs of the body

1. Superior vena cava
2. Inferior vena cava
3. Aorta
4. Pulmonary Vein

Explanation

Circulation of oxygenated blood from the left ventricle of the heart to various organs of the body and return of deoxygenated blood to the right atrium. Aorta carries oxygenated blood to all the organs of the body.

83. The path of pulmonary circulation starts in_______

1. Right auricle
2. Right Ventricle
3. Left Ventricle
4. Left Auricle

Explanation

The path of pulmonary circulation starts in the right ventricle. Pulmonary artery arises from the right ventricle and reaches the lungs with deoxygenated blood.

84. _____collect the oxygenated blood from the lungs and supplies it to the left atrium

1. Superior vena cava
2. Inferior vena cava
3. Aorta
4. Pulmonary Vein

Explanation

Pulmonary veins collect the oxygenated blood from the lungs and supplies it to the left atrium of the heart.

85. Which of the following statement is correct?

1. The supply of blood to the heart muscles (cardiac muscles) is called as coronary circulation.
2. Cardiac muscles receive oxygenated blood from coronary arteries that originate from the aortic arch.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The supply of blood to the heart muscles (cardiac muscles) is called as coronary circulation. Cardiac muscles receive oxygenated blood from coronary arteries that originate from the aortic arch. Deoxygenated blood from the cardiac muscles drains into the right atrium by the coronary sinuses.

86. Which of the following statement is incorrect?

1. When the blood circulates twice through the heart in one complete cycle it is called double circulation.
2. In double circulation the oxygenated blood do not mix with the deoxygenated blood
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

When the blood circulates twice through the heart in one complete cycle it is called double circulation. In double circulation the oxygenated blood do not mix with the deoxygenated blood.

87.In which of the following Single circulation is found?

1. Fishes
2. Reptiles
3. Amphibians
4. All the above

Explanation

In some animals the oxygenated and deoxygenated blood are mixed and pass through the heart only once. This type of circulation is called single circulation. e.g., fishes, amphibians and certain reptiles.

88. The heart normally beats____ times per minute

1. 72 to 80
2. 72 to 75
3. 73 to 77
4. 80 to 88

Explanation

One complete contraction (systole) and relaxation (diastole) of the atrium and ventricles of the heart constitute heartbeat. The heart normally beats 72 – 75 times per minute.

89. Which of the following statement is correct?

1. The human heart is myogenic in nature.
2. The SA node is broader at the top and tapering below
3. It is made up of thin fibres
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The human heart is myogenic in nature. Contraction is initiated by a specialized portion of the heart muscle, the Sino-atrial (SA) node which is situated in the wall of the right atrium near the opening of the superior vena cava. The SA node is broader at the top and tapering below. It is made up of thin fibres.

90. _____ acts as the ‘pacemaker’ of the heart

1. Myogenic node
2. Neurogenic node
3. Sino-atrial node
4. None

Explanation

Sino-atrial node acts as the ‘pacemaker’ of the heart because it is capable of initiating impulse which can stimulate the heart muscles to contract.

91. Atrioventricular bundle was discovered by_____

1. Thomas Hardy
2. Thomas Harvey
3. William Harvey
4. His

Explanation

The wave of contraction from SA node reaches the atrioventricular (AV) node which is stimulated to emit an impulse of contraction spreading to the ventricular muscle via the atrioventricular bundle and the Purkinje fibres. Atrioventricular bundle was discovered by His (1893). So is called Bundle of His.

92. Normal pulse rate ranges from___ / min

1. 80 to 120
2. 70 to 90
3. 60 to 80
4. 70 to 110

Explanation

When the heart beats the blood is forced into the arteries. The expansion of the artery every time the blood is forced into it is called pulse. It can be felt by placing the fingertip on the artery near the wrist. Normal pulse rate ranges from 70 – 90 / min.

93. Each cardiac cycle lasts about______ sec

1. 0.3
2. 0.8
3. 0.11
4. 0.5

Explanation

The sequence of events occurring from the beginning to the completion of one heart beat is called cardiac cycle. During cardiac cycle blood flows through the chambers of the heart in a specific direction. Each cardiac cycle lasts about 0.8 second.

94. Match the following

1. Atrial systole 1. 0.4 sec
2. Ventricular systole 2. 0.1 sec
3. Ventricular diastole 3. 0.3 sec
4. 2, 1, 3
5. 2, 3, 1
6. 3, 1, 2
7. 1, 3, 2

Explanation

• Atrial systole: Contraction of auricles (0.1 sec)
• Ventricular systole: Contraction of ventricles (0.3 sec)
• Ventricular diastole: Relaxation of ventricles (0.4 sec)

95. Which of the following statement is correct?

1. The rhythmic closure and opening of the valves cause the sound of the heart
2. The first sound LUBB is short duration
3. The second sound DUPP is of a shorter duration
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The rhythmic closure and opening of the valves cause the sound of the heart. The first sound LUBB is of longer duration and is produced by the closure of the tricuspid and bicuspid valves after the beginning of ventricular systole. The second sound DUPP is of a shorter duration and produced by the closure of semilunar valves at the end of ventricular systole.

96. Which of the following statement is correct?

1. Blood pressure is the force exerted during the flow of blood against the lateral walls of arteries
2. Blood pressure is usually expressed in terms of the systolic pressure and diastolic pressure
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Blood pressure is the force exerted during the flow of blood against the lateral walls of arteries. The blood pressure is high in the arteries gradually drops in the arterioles and capillaries and become very low in the veins. Blood pressure is usually expressed in terms of the systolic pressure and diastolic pressure.

97. Which of the following statement is correct?

1. During ventricular systole, the left ventricle contracts and forces blood into the aorta
2. The pressure rises to a peak which is referred as Diastolic pressure
3. During diastole, the ventricles relax and the pressure falls to the lowest value which is referred as diastolic pressure
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Systolic pressure: During ventricular systole, the left ventricle contracts and forces blood into the aorta. The pressure rises to a peak which is referred as systolic pressure

Diastolic pressure: During diastole, the ventricles relax and the pressure falls to the lowest value which is referred as diastolic pressure.

98. In a healthy adult systolic and diastolic blood pressure is expressed a____ mm Hg

1. 70 to 110
2. 80 to 120
3. 90 to 130
4. 80 to 100

Explanation

In a healthy adult during normal resting condition systolic and diastolic blood pressure is expressed as 120mm / 80mm Hg. Blood pressure varies during conditions of physical exercise, anxiety, emotions, stress and sleep.

99. Which of the following statement is correct?

1. Decrease in blood pressure is termed hypotension
2. A prolonged or constant elevation of blood pressure is a condition known as hypertension
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

A prolonged or constant elevation of blood pressure is a condition known as hypertension (High blood pressure) can increase the risk of heart attack and stroke. Decrease in blood pressure is termed hypotension (Low blood pressure)

100. _____ is used to detect the sound produced by the internal organs of human body

1. Sphygmomanometer
2. Pulse Oximeter
3. Stethoscope
4. Thermometer

Explanation

A stethoscope is used to detect the sound produced by the internal organs of human body. The heart sound is heard by placing the stethoscope on the chest.

101. Which of the following statement is correct?

1. Sphygmomanometer is a clinical instrument used to measure blood pressure when a person is in a relaxed and resting condition
2. It helps to diagnose conditions such as increased or decreased blood pressure.
3. Monometric and modern digital types are the apparatus used to measure blood pressure
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Sphygmomanometer is a clinical instrument used to measure blood pressure when a person is in a relaxed and resting condition. The pressure of the brachial artery is measured. It helps to diagnose conditions such as increased or decreased blood pressure. Monometric and modern digital types are the apparatus used to measure blood pressure.

102. The concept of blood grouping was developed by______

1. William Digboi
2. William Harvey
3. Harvey Dent
4. Karl Landsteiner

Explanation

The concept of blood grouping was developed by Karl Landsteiner (1900). He identified blood groups A, B and O. AB blood group was recognized by Decastello and Steini (1902).

103. Which of the following statement is correct?

1. Human blood contains certain specific substances called agglutinogens or antigens and agglutinins or antibodies
2. Human blood group is classified into five groups called A, B, C, AB and O
3. Antigens are found on the membrane surface of RBC
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Human blood contains certain specific substances called agglutinogens or antigens (Ag) and agglutinins or antibodies (Ab). Antigens are found on the membrane surface of RBC. Antibodies are present in blood plasma. Based on the presence or absence of antigen and antibodies human blood group is classified into four groups called A, B, AB and O.

104. Which of the following statement is correct?

1. In ‘A’ group individuals, Antigen A is present on the surface of RBC and antibody b (anti-b) is present in the plasma
2. In ‘B’ group individuals, Antigen B is present on the surface of RBC and antibody a (anti – a) is present in the plasma.
3. In ‘O’ group individuals, Antigen A or B are absent on the surface of RBC.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

• A’ group individuals: Antigen A is present on the surface of RBC and antibody b (anti-b) is present in the plasma.
• ‘B’ group individuals: Antigen B is present on the surface of RBC and antibody a (anti – a) is present in the plasma.
• ‘AB’ group individuals: Antigens A and B are present on the surface of RBC and antibodies are absent in the plasma.
• ‘O’ group individuals: Antigen A or B are absent on the surface of RBC. However, the plasma contains both antibodies a and b (anti a and b).

105. _________ blood group are called ‘Universal Recipient’

1. A
2. B
3. AB
4. O

Explanation

In blood transfusion one must consider the antigen and antibody compatibility (matching) between the donor and the person receiving blood (recipient). Persons with ‘AB’ blood group are called ‘Universal Recipient’ as they can receive blood from persons with any blood group.

106. _____ blood group are called ‘Universal Donor’

1. A
2. AB
3. O
4. B

Explanation

Persons with ‘O’ blood group are called ‘Universal Donor’ as they can donate blood to persons with any blood group

107. Which of the following statement is correct?

1. Rh factor was discovered by Landsteiner and Wiener in 1940 in Rhesus monkey
2. The surface of WBC contains the antigen for Rh factor.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Rh factor was discovered by Landsteiner and Wiener in 1940 in Rhesus monkey. The surface of RBC contains the antigen for Rh factor. Rh+ (positive) persons have Rh antigen on the surface of RBC while, Rh– (negative) persons do not have Rh antigen on the surface of RBC. Antibodies developed against this Rh antigen is called Rh antibodies.

108.Which of the following does not form the part of lymphatic system?

1. Lymph node
2. Lymphatic Ducts
3. Lymphatic capillaries
4. None

Explanation

The lymphatic system comprises of lymphatic capillaries, lymphatic vessels, lymph nodes and lymphatic ducts. Lymph is the fluid that flows through the lymphatic system.

109. The lymphatic capillaries unite to form large________

1. Lymph node
2. Lymphatic Ducts
3. Lymphatic Veins
4. Lymphatic Vessels

Explanation

The lymphatic capillaries unite to form large lymphatic vessels. Lymph nodes are small oval or pear-shaped structures located along the length of lymphatic vessels.

110. Which of the following statement is correct?

1. Lymph from the intercellular spaces drains into lymphatic capillaries.
2. Lymph is a colourless fluid formed when plasma, proteins and blood cells escape into intercellular spaces in the tissues through the pores present in the walls of capillaries.
3. The lymph contains very small amount of nutrients, oxygen, CO2, water and WBC
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Lymph from the intercellular spaces drains into lymphatic capillaries. Lymph is a colourless fluid formed when plasma, proteins and blood cells escape into intercellular spaces in the tissues through the pores present in the walls of capillaries. It is similar to blood plasma, but is colourless and contains less proteins. The lymph contains very small amount of nutrients, oxygen, CO2, water and WBC.

111. Which of the following are the functions of Lymph?

1. Supplies nutrition and oxygen to all parts where blood can reach
2. The lymph also carries absorbed fats from small intestine to the blood
3. Lymphocytes in the lymph defend the body from infections
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Functions of Lymph:

• Supplies nutrition and oxygen to those parts where blood cannot reach
• It drains away excess tissue fluid and metabolites and returns proteins to the blood from tissue spaces.
• The lymph also carries absorbed fats from small intestine to the blood. The lymphatic capillaries of intestinal villi (lacteals) absorb digested fats.
• Lymphocytes in the lymph defend the body from infections.

10th Science Lesson 15 Questions in English

15] Nervous System

1. Which of the following statement is incorrect?

1. One of the characteristic features of all living organisms is responding to stimuli
2. Stimulus refers to the changes in the environmental condition, that are detected by receptors present in the body
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

One of the characteristic features of all living organisms is responding to stimuli. Stimulus refers to the changes in the environmental condition, that are detected by receptors present in the body

2. To which of the following living organism responds to?

1. Heat
2. Light
3. Force of gravity
4. Smell
5. 1, 2, 3
6. 1, 2, 4
7. 2, 3, 4
8. All the above

Explanation

Relevant changes in the activities of organisms to a particular- stimuli are called their reactions or responses. Living organisms show their response to different kinds of stimuli like light, heat, cold, sound, smell, taste, touch, pressure, pain or the force of gravity etc.

3. Which of the following statement is correct?

1. To provide the correct response to a stimulus, it is necessary that all the organs work together in a proper coordinated manner
2. The working together of various organs in a systematic, controlled and efficient way to produce proper response to various stimuli is called coordination
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

To provide the correct response to a stimulus, it is necessary that all the organs work together in a proper coordinated manner. This working together of various organs in a systematic, controlled and efficient way to produce proper response to various stimuli is called coordination.

4. Cells and organs is essential for their diverse activities to maintain physiological balance called_________

1. Homeolysis
2. Homeostasis
3. Homeotherm
4. Homo erectus

Explanation

In animals including human the coordination between the various cells and organs is essential for their diverse activities to maintain physiological balance called homeostasis.

5. How many distinct components are there in Nervous system?

1. 2
2. 4
3. 3
4. 5

Explanation

The nervous system is made up of nervous tissues. It is formed of three distinct components namely the neurons, neuroglia and nerve fibres.

6. ______ is the structural and functional unit of the nervous system

1. Nerve cell
2. Neuroglia
3. Nerve fibre
4. All the above

Explanation

A neuron or nerve cell is the structural and functional unit of the nervous system. Information is conducted through neurons in the form of electrical impulses from one part of the body to another.

7. What is the length of Neuron?

1. 100µm
2. 10mm
3. 1µm
4. 20µm

Explanation

Neuron or nerve cell is the longest cell of the human body with a length of over 100µm. These cells are highly specialised to detect, receive and transmit different kinds of stimuli.

8. ______ are also called as glial cells

1. Neuron
2. Neuroglia
3. Nerve fibre
4. All the above

Explanation

Neuroglia is also called as glial cells. They are non-exciting, supporting cell of the nervous system. They do not initiate or conduct nerve impulses.

9. Which of the following statement about nerve fibre is correct?

1. The nerve fibres are the long slender processes of neurons
2. A number of nerve fibres are bundled up together to form nerves
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The nerve fibres are the long slender processes of neurons. A number of nerve fibres are bundled up together to form nerves.

10. How many basic parts does neurons have?

1. 4
2. 5
3. 2
4. 3

Explanation

A neuron typically consists of three basic parts: Cyton, Dendrites and Axon. A neuron or nerve cell is the structural and functional unit of the nervous system.

11. Which of the following statement about Cyton is correct?

1. Cyton is also called cell body or perikaryon
2. It has a central nucleus with abundant cytoplasm called neuroplasm.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Cyton is also called cell body or perikaryon. It has a central nucleus with abundant cytoplasm called Neuroplasm.

12. Which of the following statement is correct?

1. Neurons have the ability to divide
2. Several neurofibrils are present in the cytoplasm that help in transmission of nerve impulses to and from the cell body
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The cytoplasm has large granular body called Nissl’s granules and the other cell organelles like mitochondria, ribosomes, lysosomes, and endoplasmic reticulum. Neurons do not have the ability to divide. Several neurofibrils are present in the cytoplasm that help in transmission of nerve impulses to and from the cell body.

13. _____ conduct nerve impulses towards the cyton

1. Axon
2. Dendrites
3. Glial cells
4. All the above

Explanation

Dendrites are the numerous branched cytoplasmic processes that project from the surface of the cell body. They conduct nerve impulses towards the cyton.

14. Which of the following statement is correct?

1. The axon is a single, elongated, slender projection
2. The end of axon terminates as fine branches which terminate into knob like swellings called synaptic knob
3. It carries impulses away from the dendron
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The axon is a single, elongated, slender projection. The end of axon terminates as fine branches which terminate into knob like swellings called synaptic knob. The plasma membrane of axon is called axolemma, while the cytoplasm is called axoplasm. It carries impulses away from the cyton. The axons may be covered by a protective sheath called myelin sheath which is further covered by a layer of Schwann cells called neurilemma.

15. Which of the following statement is correct?

1. Myelin sheath breaks at intervals by depressions called Nodes of Ranvier
2. Myelin sheath acts as insulator and ensures rapid transmission of nerve impulses
3. The region between the nodes is called as internode
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The axons may be covered by a protective sheath called myelin sheath which is further covered by a layer of Schwann cells called neurilemma. Myelin sheath breaks at intervals by depressions called Nodes of Ranvier. The region between the nodes is called as internode. Myelin sheath acts as insulator and ensures rapid transmission of nerve impulses.

16. Which of the following statement is correct?

1. A junction between synaptic knob of axon of one neuron and Cyton of next neuron is called synaptic junction
2. Information from one neuron can pass to another neuron through these junctions with the release of chemicals known as neurotransmitters
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

A junction between synaptic knob of axon of one neuron and dendron of next neuron is called synaptic junction. Information from one neuron can pass to another neuron through these junctions with the release of chemicals known as neurotransmitters from the synaptic knob.

17. Which of the following statement is correct?

1. Only one nerve process arises from the cyton which acts as both axon and dendron in Bipolar neuron
2. The cyton gives rise to many dendrons and an axon in Multipolar neuron
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Structurally the neurons may be of the following types:

• Unipolar neurons: Only one nerve process arises from the cyton which acts as both axon and dendron.
• Bipolar neurons: The cyton gives rise to two nerve processes of which one acts as an axon while another as a dendron
• Multipolar neurons: The cyton gives rise to many dendrons and an axon

18. Match the following

1. Unipolar Neurons 1. Found in cerebral cortex of brain
2. Bipolar Neurons 2. Found in early embryos only
3. Multipolar Neurons 3. Found in retina of eye
4. 2, 1, 3
5. 2, 3, 1
6. 3, 1, 2
7. 3, 2, 1

Explanation

Unipolar Neurons- Found in early embryos but not in adult

Bipolar Neurons- Found in retina of eye and olfactory epithelium of nasal chambers

Multipolar Neurons- Found in cerebral cortex of brain

19. Match the following

1. Sensory neurons 1. Impulses from CNS to effector organ
2. Motor neurons 2. Impulses from the sense organ to the CNS
3. Association neurons 3. Impulses between sensory and motor neurons
4. 2, 1, 3
5. 2, 3, 1
6. 3, 2, 1
7. 1, 3, 2

Explanation

• Sensory or afferent neurons which carry impulses from the sense organ to the central nervous system.
• Motor or efferent neurons which carry impulses from the central nervous system to effector organ such as the muscle fibre or the gland.
• Association neurons conduct impulses between sensory and motor neurons.

20. Which of the following statement is correct?

1. Nerve fibres are of two types based on the presence or absence of myelin sheath
2. Myelinated and non-myelinated nerve fibres form the white matter and grey matter of the brain
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Nerve fibres are of two types based on the presence or absence of myelin sheath. Myelinated and non-myelinated nerve fibres form the white matter and grey matter of the brain.

21. Which of the following statement is incorrect?

1. In Myelinated nerve fibre, axon is covered with myelin sheath
2. In Non-myelinated nerve fibre, axon is not covered by myelin sheath
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Myelinated nerve fibre: The axon is covered with myelin sheath

Non-myelinated nerve fibre: The axon is not covered by myelin sheath.

22. Which of the following is not a receptor organ?

1. Skin
2. Eyes
3. Pharynx
4. Nose

Explanation

All the information from the environment are detected by the receptors located in our sense organs such as the eyes, the nose, the skin, etc.

23. Which of the following statement is correct?

1. Information from the receptors is transmitted as electrical impulse and is received by the dendritic tips of the neuron
2. This impulse travels from the dendrite to the cell body and then along the axon to its terminal end
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Information from the receptors is transmitted as electrical impulse and is received by the dendritic tips of the neuron. This impulse travels from the dendrite to the cell body and then along the axon to its terminal end. On reaching the axonal end, it causes the nerve endings to release a chemical (neurotransmitter) which diffuses across a synapse and starts a similar electrical impulse in the dendrites of the next neuron, then to their cell body to be carried along the axon.

24. The flow of nerve impulses from axonal end of one neuron to dendrite of another neuron through____________

1. Axon
2. Cyton
3. Dendron
4. Synapse

Explanation

The flow of nerve impulses from axonal end of one neuron to dendrite of another neuron through a synapse is called synaptic transmission.

25. Each neuron can transmit____ nerve impulses per second

1. 100
2. 1000
3. 10
4. 500

Explanation

Each neuron can transmit 1000 nerve impulses per second and make as many as ten thousand of synaptic contacts with other neurons.

26. The important neurotransmitter released by neurons is called_____

1. Prolactin
2. Lipase
3. Acetylcholine
4. Chloroquine

Explanation

Neurotransmitters are the chemicals which allow the transmission of nerve impulse from the axon terminal of one neuron to the dendron of another neuron or to an effector organ. The important neurotransmitter released by neurons is called Acetylcholine.

27. Which of the following statement is correct?

1. The complexity of nervous system can be observed during the course of evolution
2. We the human beings differ from other animals in our ability to think and take actions, which is due to the well-developed nervous system.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The complexity of nervous system can be observed during the course of evolution. We the human beings differ from other animals in our ability to think and take actions, which is due to the well-developed nervous system.

28. Human nervous system is differentiated into_____

1. 2
2. 3
3. 5
4. 4

Explanation

Human nervous system is differentiated into three: central nervous system (CNS), peripheral nervous system (PNS) and autonomic nervous system (ANS).

29. ______ consists of the brain and the spinal cord

1. CNS
2. ANS
3. PNS
4. All the above

Explanation

The CNS acts as centre for information processing and control. It consists of the brain and the spinal cord. The PNS is made up of the nerves which connect the brain and spinal cord to all parts of the body. The ANS is formed of sympathetic and parasympathetic nerves.

30. Which of the following statement is correct?

1. The brain and the spinal cord being delicate vital structures are well protected in bony cavities of the skull and the vertebral column respectively
2. PNS is formed of two types of matter such as white matter or grey matter
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The brain and the spinal cord being delicate vital structures are well protected in bony cavities of the skull and the vertebral column respectively. CNS is formed of two types of matter such as white matter or grey matter with respect to the presence or absence of myelin sheath which we have discussed earlier.

31. The brain is covered by _____ connective tissue membrane

1. 2
2. 5
3. 3
4. 4

Explanation

The brain is the controlling centre of all the body activities. It is covered by three connective tissue membrane or meninges.

32. Match the following

1. Duramater 1. Innermost
2. Arachnoid membrane 2. Outermost
3. Piamater 3. Middle membrane
4. 1, 3, 2
5. 2, 3, 1
6. 1, 2, 3
7. 2, 1, 3

Explanation

• Duramater (dura: tough; mater: membrane) is the outermost thick fibrous membrane
• Arachnoid membrane (arachnoid: spider) is the middle, thin vascular membrane providing web like cushion
• Piamater (Pia: soft or tender) is the innermost, thin delicate membrane richly supplied with blood.

33. The most common causes of meningitis______

1. Bacterial
2. Viral
3. Fungal
4. 1, 2
5. 1 alone
6. 2 alone
7. All the above

Explanation

Meningitis is an inflammation of the meninges. It can occur when fluid surrounding the meninges becomes infected. The most common causes of meningitis are viral and bacterial infections.

34. A human brain is formed of___ main parts

1. 2
2. 4
3. 3
4. 5

Explanation

Meningeal membranes protect the brain from mechanical injury. A human brain is formed of three main parts: (a) forebrain (b) midbrain and (c) hindbrain.

35. The forebrain is formed of____

1. Cerebellum
2. Cerebrum
3. Pons
4. Diencephalon
5. 2, 3
6. 2, 4
7. 1, 3, 4
8. All the above

Explanation

The forebrain is formed of cerebrum and diencephalon. The latter consists of dorsal thalamus and ventral hypothalamus.

36. Cerebrum is nearly____ of the brain

1. Two third
2. Three fourth
3. One fourth
4. Two fifth

Explanation

Cerebrum is the largest portion forming nearly two third of the brain. The cerebrum is longitudinally divided into two halves as right and left cerebral hemispheres by a deep cleft called median cleft.

37. The outer portion of each cerebral hemisphere is formed of____ matter

1. White
2. Grey
3. Both a and b
4. Reddish Brown

Explanation

Two cerebral hemispheres are interconnected by thick band of nerve fibres called corpus callosum. The outer portion of each cerebral hemisphere is formed of grey matter and is called cerebral cortex.

38. The inner or deeper part is formed of_____ matter

1. White
2. Grey
3. Both a and b
4. Reddish Brown

Explanation

The inner or deeper part is formed of white matter and is called cerebral medulla. The cortex is extremely folded forming elevations called gyri with depressions between them termed as sulci that increase its surface area.

39. Each cerebral hemisphere is divisible into_____ lobes

1. 2
2. 3
3. 4
4. 5

Explanation

Each cerebral hemisphere is divisible into four lobes: a frontal lobe, a parietal lobe, a temporal lobe and an occipital lobe. These lobes are also known as cerebral lobes and are associated with specific functions. Any damage in specific lobe in-turn affects its function.

40. The cerebrum is responsible for______

1. Willpower
2. Memory
3. Thinking
4. Imagination
5. 1, 2, 3
6. 1, 2, 4
7. 2, 3, 4
8. All the above

Explanation

The cerebrum is responsible for the thinking, intelligence, consciousness, memory, imagination, reasoning and willpower.

41. _____ is a major conducting centre for sensory and motor signalling

1. Hypothalamus
2. Thalamus
3. Cerebrum
4. Cerebellum

Explanation

Thalamus present in cerebral medulla is a major conducting centre for sensory and motor signalling. It acts as a relay centre.

42. Which of the following statement about hypothalamus is correct?

1. It lies at the base of the thalamus
2. It controls sexual desire
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Hypothalamus lies at the base of the thalamus. It controls involuntary functions like hunger, thirst, sleep, sweating, sexual desire, anger, fear, water balance, blood pressure etc.

43. _____ acts as the acts as a thermoregulatory centre of the body

1. Thalamus
2. Hypothalamus
3. Medulla Oblongata
4. Pons

Explanation

Hypothalamus acts as a thermoregulatory (temperature control) centre of the body. It controls the secretion of hormones from anterior pituitary gland and is an important link between nervous system and endocrine system.

44. Which of the following statement about midbrain is correct?

1. It is located between thalamus and hind brain.
2. It controls visual and auditory (hearing) reflexes
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Midbrain is located between thalamus and hind brain. The dorsal portion of the mid brain consists of four rounded bodies called corpora quadrigemina that control visual and auditory (hearing) reflexes.

45. Hind Brain formed of___ parts

1. 2
2. 3
3. 4
4. 5

Explanation

A human brain is formed of three main parts: (a) forebrain (b) midbrain and (c) hindbrain. Hindbrain is formed of three parts cerebellum, pons and medulla oblongata.

46. Which of the following statement is correct?

1. The human brain constitutes nearly 90 percent of fat
2. EFAs cannot be synthesised and must be obtained from food.
3. Fish, green leafy vegetables, almond, walnut are rich sources of EFAs
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The human brain constitutes nearly 60 percent of fat. The most crucial molecules that determine our brain’s integrity and the ability are Essential Fatty Acids (EFAs). EFAs cannot be synthesised and must be obtained from food. Fish, green leafy vegetables, almond, walnut are rich sources of EFAs.

47. ______is second largest part of the brain

1. Cerebrum
2. Cerebellum
3. Pons
4. Medulla Oblongata

Explanation

Cerebellum is second largest part of the brain formed of two large sized hemispheres and middle vermis. It coordinates voluntary movements and also maintains body balance.

48. Which of the following controls sleep cycle?

1. Cerebrum
2. Cerebellum
3. Pons
4. Medulla Oblongata

Explanation

‘Pons’ a latin word meaning bridge. It is a bridge of nerve fibre that connects the lobes of cerebellum. It relays signals between the cerebellum, spinal cord, midbrain and cerebrum. It controls respiration and sleep cycle.

49. Which of the following statement is correct?

1. Medulla oblongata is the anterior most part of the brain that connects spinal cord and various parts of brain
2. It also regulates vomiting and salivation.
3. It has cardiac centres, respiratory centres, vasomotor centres to control heart beat
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Medulla oblongata is the posterior most part of the brain that connects spinal cord and various parts of brain. It has cardiac centres, respiratory centres, vasomotor centres to control heart-beat, respiration and contractions of blood vessels respectively. It also regulates vomiting and salivation.

50. Match the following

1. Cerebral cortex 1. Role in sleep-awake cycle
2. Thalamus 2. Creativity
3. Cerebellum 3. Acts as relay station
4. Pons 4. Maintenance of posture and balance
5. 2, 1, 3, 4
6. 2, 3, 4, 1
7. 1, 3, 2, 4
8. 3, 1, 4, 2

Explanation

51. Which of the following abnormalities can a EEG detect?

1. Cardiac arrest
2. Seizure
3. Epilepsy
4. Head Injury
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

Electroencephalogram (EEG) is an instrument which records the electrical impulses of brain. An EEG can detect abnormalities in the brain waves and help in diagnoses of seizures, epilepsy, brain tumor, head injuries, etc.

52. Which of the following statement is correct?

1. Spinal cord is a cylindrical structure lying in the neural canal of the vertebral column.
2. It is also covered by meninges
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Spinal cord is a cylindrical structure lying in the neural canal of the vertebral column. It is also covered by meninges.

53. Spinal Cord extends from the lower end of_____

1. Cerebrum
2. Cerebellum
3. Hypothalamus
4. Medulla Oblongata

Explanation

Spinal cord extends from the lower end of medulla oblongata to the first lumbar vertebra. The posterior most region of spinal cord tapers into a thin fibrous thread like structure called filum terminal.

54. The grey matter of spinal cord is___ shaped.

1. L
2. H
3. S
4. O

Explanation

Internally, the spinal cord contains a cerebrospinal fluid filled cavity known as the central canal. The grey matter of spinal cord is ‘H’ shaped. The upper end of letter ‘H” forms posterior horns and lower end forms anterior horns.

55. Which of the following statement about spinal cord is correct?

1. A bundle of fibre pass into the posterior horn of Spinal cord forming dorsal or afferent root
2. The white matter is external and have bundle of nerve tracts.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The upper end of letter ‘H” forms posterior horns and lower end forms anterior horns. A bundle of fibre pass into the posterior horn forming dorsal or afferent root. Fibres pass outward from the anterior horn forming ventral or efferent root. These two root joins to form spinal nerves. The white matter is external and have bundle of nerve tracts

56. Spinal cord conducts______ impulses to and from the brain.

1. Motor
2. Sensory
3. Optical
4. 1 alone
5. 2 alone
6. 1, 2
7. None

Explanation

Spinal cord conducts sensory and motor impulses to and from the brain. It controls reflex actions of the body.

57. Which of the following statement is incorrect?

1. The brain is suspended in a special fluid environment called cerebrospinal fluid
2. It is lymph like, watery fluid that surrounds and protects the brain within the skull
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

The brain is suspended in a special fluid environment called cerebrospinal fluid (CSF). It is lymph like, watery fluid that surrounds and protects the brain within the skull. It also fills the central canal of the spinal cord.

58. Which of the following are the functions of Cerebrospinal Fluid?

1. It supplies nutrients from the brain
2. It is also responsible for maintaining a constant pressure inside the cranium.
3. It acts as shock absorbing fluid
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Functions of Cerebrospinal fluid:

• It acts as shock absorbing fluid and protects the brain from damage when it is subjected to sudden jerk.
• It supplies nutrients to the brain
• It collects and removes wastes from the brain.
• It is also responsible for maintaining a constant pressure inside the cranium.

59. Which of the following statement is correct?

1. A reflex is any response that occurs automatically with consciousness
2. There are two types of reflexes.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

A reflex is any response that occurs automatically without consciousness. There are two types of reflexes.

• Simple or basic reflexes
• Acquired or conditioned reflexes

60. Which of the following is not a Simple or basic reflex?

1. Yawning
2. Sneezing
3. Playing harmonium
4. Coughing

Explanation

Simple or basic reflexes These reflexes are inbuilt and unlearned responses. Many of the actions we perform in our day to day life are simple reflexes. e.g., winking of eyes when any dust particles enter, sneezing, coughing, yawning, etc. We perform these actions without thinking

61. Which of the following statement is correct about conditioned reflexes?

1. These reflexes are the result of practice and learning
2. Playing harmonium by striking a particular key on seeing a music note is an example of conditioned reflexes
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Acquired or conditioned reflexes are the result of practice and learning. Playing harmonium by striking a particular key on seeing a music note is an example of conditioned reflexes which required conscious training effort.

62. Peripheral nervous system is formed by_________

1. Nerves from brain
2. Nerves from spinal cord
3. Nerves from heart
4. 1, 3
5. 2, 3
6. 1, 2
7. All the above

Explanation

Peripheral nervous system is formed by the nerves arising from the brain and the spinal cord. The nerves arising from the brain are called cranial nerves. Nerves arising from spinal cord are called spinal nerves.

63. In man, there are____ pairs of cranial nerves

1. 11
2. 31
3. 12
4. 24

Explanation

In man, there are 12 pairs of cranial nerves. Some of the cranial nerves are sensory e.g. optic nerve which innervates the eye. Some are motor nerves which helps in rotation of eyeball. It also innervates the eye muscles, muscles of iris and tear gland.

64. There are___ pairs of spinal nerves

1. 31
2. 13
3. 12
4. 24

Explanation

There are 31 pairs of spinal nerves. Each spinal nerve has a dorsal sensory root and the ventral motor root. The direction of impulses in dorsal spinal root is towards the spinal cord and in ventral spinal root away from the spinal cord.

65. __________ is also called as visceral nervous system

1. PNS
2. ANS
3. CNS
4. None

Explanation

Autonomic nervous system (ANS) is also called as visceral nervous system as it regulates the function of internal visceral organs of our body through its two antagonistic (opposite) components sympathetic and parasympathetic systems.

66.____ controls the involuntary functions of the visceral organs

1. PNS
2. ANS
3. CNS
4. None

Explanation

Autonomic nervous system (ANS) enables the body to perform rapid and specific visceral activities in order to maintain steady state. It controls the involuntary functions of the visceral organs.