7th Std Science Lesson Wise Questions in English – Part 2

7th Science Lesson 9 Questions in English

9] Changes Around Us

1. Which of the following is/are physical change?

1. Ice melts on heating
2. Water starts evaporating
3. Freezing of water
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Changes take place around us all the time. A change refers to an alteration in physical properties or alteration in the composition of matter. For example, ice melts on heating, that is, it changes from a solid to liquid. On further heating, water starts evaporating; it changes from a liquid to gas. Here, there is a change in the physical state of the substance.

2. Which of the following are altered by physical changes?

1. Colour
2. Texture
3. State of the substance
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Let us look at another change, that is, when objects made of iron are exposed to moist conditions, a reddish-brown new substance called rust forms on the surface of these objects. In this instance of rusting, there is change in the composition of the substance. Thus, the physical changes involve an alteration in the properties such as colour, texture and the state of the substance since there is formation of a new substance.

3. Which of the following is chemical change?

1. Butter melting
2. Nail rusting
3. Bread making
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

4. Which of the following gas is liberated when paper is burnt?

1. Oxygen
2. Carbon Monoxide
3. Carbon di-oxide
4. Nitrogen

Explanation

In case of burning of paper, changes to carbon dioxide and other substances. Now we cannot get back the paper after burning. As there is a change in the chemical nature, it is called as chemical change.

5. Heating of a substance results in_______

1. Expansion
2. Distribution
3. Contraction
4. Either a or c

Explanation

Upon heating, particle arrangement within the state of matter gets disturbed. The disturbance is seen either as expansion or contraction.

6. Which of the following remains the same when an object is cooled?

1. Shape
2. Mass
3. Size
4. All the above

Explanation

When heated or cooled, the object may expand or contract based on the nature of the object, but the mass remains the same. That is, the number of particles that was inside the object does not undergo any change, only the arrangement of the particle changes.

7. When a glass of water is heated, its volume______

1. Decreases
2. Increases
3. Initially increases then decreases
4. Remains the same

Explanation

When a glass of water is heated, its volume increases and in case a glass of water is cooled its volume decreases.

8. Which of the following statement about solid is correct?

1. Parti­cles are very close together
2. Parti­cles are not arranged in a fixed regular pattern
3. Particles can vibrate about their fixed posi­tions
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

9. Which of the following statement about liquid is correct?

1. Particles are apart from each other
2. Parti­cles are not arranged in a fixed regular pattern
3. Parti­cles are able to slide past one another.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

10. Which of the following statement about gas is correct?

1. Particles are apart from each other
2. Parti­cles are not arranged in a fixed regular pattern
3. Parti­cles move freely over long distances.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

11. Which of the following are the effects of heat gain?

1. May result in Melting, Boiling, Freezing and Condensation
2. Brings change in state
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

12. Which of the following statement is correct?

1. Physical changes are the changes in which only physical properties of a substance undergo a change
2. There is no new substance formed in a physical change
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Physical changes are the changes in which only physical properties of a substance undergo a change and there is no change in its chemical composition. There is no new substance formed in a physical change.

13. Which of the following are physical properties?

1. Lustre
2. Ductility
3. Viscosity
4. Density
5. 1, 2, 3
6. 1, 3, 4
7. 2, 3, 4
8. All the above

Explanation

Physical properties include lustre, malleability (flexibility), and ductility (ability to be drawn into a thin wire), density, viscosity, solubility, mass, volume and so on. Any change in these physical properties is referred to as a physical change.

14. Assertion(A): when a rubber band is stretched, it elongates

Reason(R): Stretching of rubber band is chemical change

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

Any change in these physical properties is referred to as a physical change. For example, when a rubber band is stretched, it elongates. However, when then stretching is stopped, the rubber band comes back to its original state and shape. In this example, there is no new substance formed but the rubber band remains the same before and after elongation.

15. Which of the following statement is correct?

1. During a physical change, no new substances are formed
2. A physical change is usually temporary and reversible in nature
3. In a physical change, the chemical properties of a substance do not change
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

A physical change has following characteristics:

• During a physical change, no new substances are formed. In a physical change, the chemical properties of a substance do not change. For example, when ice cube melts, water is formed. In this change, there is no new substance, but water is same both in ice and in water
• A physical change is usually temporary and reversible in nature. For example, when water is heated, water vapours are formed, once water vapours are cooled, water can be obtained again.
• In a physical change, the chemical properties of a substance do not change. For example, when a piece of gold is melted, its chemical composition remains the same in the solid form and also in the liquid form.

16. Which of the following are examples of physical change?

1. Cutting of vegetables
2. Rusting of Iron
3. Inflating a balloon
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

In a physical change, the physical properties such as colour, shape and size of a substance may undergo a change. For example, cutting of vegetables and inflating a balloon are some examples of physical changes in which size and shape of a substance undergoes a change. we know it is not

17. Match the following:

1. Solid → to Liquid 1. Sublimation
2. Liquid → to Solid 2. Melting
3. Solid → to Gas 3. Freezing
4. Gas → to Liquid 4. Condensation
5. 3, 1, 2, 4
6. 2, 3, 1, 4
7. 2, 3, 4, 1
8. 3, 4, 1, 2

Explanation

The following are some of the changes of state:

from Solid → to Liquid is Melting

from Liquid → to Gas is Vaporization

from Liquid → to Solid is Freezing

from Gas → to Liquid is Condensation

from Solid → to Gas is Sublimation

18. In an endothermic process, the speed of the molecules____

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

Explanation

In an endothermic process, heat is absorbed and the speed of the molecules is increased hence they move faster.

19. Which of the following process are endothermic process?

1. Melting
2. Freezing
3. Vaporization
4. Sublimation
5. 1, 2, 4
6. 1, 3, 4
7. 2, 3, 4
8. All the above

Explanation

Melting, vaporization, and sublimation occur when heated and hence it is called as endothermic process.

20. Which of the following statement about exothermic process is correct?

1. Heat is removed
2. It decreases the speed of molecules
3. Freezing and condensation are exothermic process
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

In contrast, such as in freezing and condensation, heat is removed, resulting in the decreasing the speed of the molecules causing them move slower. Such processes are called as exothermic process.

21. How many types of vaporization are there?

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

Explanation

When you put a wet cloth to dry, the water evaporates into air, leaving the clothes dry. That is there are two types of vaporization: boiling and evaporation, the first one is by heating and the second type of vaporization is natural.

22. Which of the following statement is correct?

1. Boiling is a physical change
2. Boiling is the process of conversion of a liquid into vapours on heating
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Boiling is the process of conversion of a liquid into vapours on heating. In gaseous state, only the arrangement of molecules changes, there is no change in their chemical composition. So, boiling is a physical change.

23. Which of the following statement is correct?

1. Upon heating a liquid, the particles gain energy and vibrate more vigorously.
2. When liquid water is heated to 100ºC, it boils to become steam
3. Boiling occurs when the boiling point is reached
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Upon heating a liquid, the particles gain energy and vibrate more vigorously. When the particles possess enough energy, they overcome the strong forces of attraction between one another. The particles break free from one another and move randomly. For example, when liquid water is heated to 100ºC, it boils to become steam. Boiling occurs when the boiling point is reached. The liquid changes to its gaseous state.

24. Which of the following statement is correct?

1. Evaporation is the technique used to separate dissolved solids from a solid-liquid mixture.
2. This is the technique used to extract salt from sea water in salt pans
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Evaporation is the technique used to separate dissolved solids from a solid-liquid mixture. This is the technique used to extract salt from sea water in salt pans.

25. Assertion(A): Salt is formed by the evaporation of sea water

Reason(R): Evaporation makes use of the fact that the solvent in a solution can vapourise at any temperature, leaving behind a residue of the solid that was dissolved in the liquid.

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

Salt is formed by the evaporation of sea water. Shallow level of sea water is impounded. Slowly the water evaporates due to action of Sun. Ultimately salt deposits over the ground we can understand. Evaporation makes use of the fact that the solvent in a solution can vapourise at any temperature, leaving behind a residue of the solid that was dissolved in the liquid.

26. Evaporation occurs at_____ of liquid

1. Surface
2. Top
3. All over the body
4. None

Explanation

From drying clothes to drying fish, evaporation is used. Evaporation is a slow process and occurs only at the surface of the liquid.

27. Upon cooling a liquid, the particles______ energy

1. Gain
2. Loose
3. Initially loose then gain
4. None

Explanation

Upon cooling a liquid, the particles loose energy and vibrate less vigorously. When the particles possess less energy, they can experience strong forces of attraction between one another. The particles move closer to each other and movement of particles is also restricted.

28. At what temperature liquid water freezes to become ice?

1. 0º C
2. 4º C
3. -1º C
4. -100º C

Explanation

When liquid water is cooled to 0º C, it freezes to become ice. Freezing occurs when the freezing point is reached. The liquid changes to its solid state.

29. Which of the following statement is correct?

1. Condensation is the conversion of gas into its liquid state
2. Condensation is neither physical nor chemical change
3. During this process, only the arrangement of molecules changes from the gaseous state to liquid state
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Condensation is the conversion of gas into its liquid state. The liquid obtained after condensation can be converted back into gas on heating. So, condensation is also a physical process. During this process, only the arrangement of molecules changes from the gaseous state to liquid state. So, condensation is a physical change.

30. Which of the following statement is incorrect?

1. Evaporation is the changing of a gas into its liquid state
2. Condensation is the changing of a liquid into its gas state
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Condensation is the changing of a gas into its liquid state and it happens by cooling, whereas Evaporation is the changing of a liquid into its gas state and it happens by heating.

31. Which of the following statement is incorrect?

1. Conversion of solid directly into gas is called sublimation.
2. There are certain solid substances like camphor, naphthalene that get converted into gas directly upon heating without becoming liquid
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

There are certain solid substances like camphor, naphthalene that get converted into gas directly upon heating without becoming liquid. This process in which a solid is converted directly into gas is called sublimation. In each of the above said processes, there is a change of state due to change in temperature. But there is no change in chemical composition.

32. Which of the following statement is correct?

1. Crystallization is a method of separation as well as a method of purification.
2. Large crystals of pure substances can be obtained from their solutions by the process of crystallization.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

crystallization is also a special form of physical change. Large crystals of pure substances can be obtained from their solutions by the process of crystallization. Crystallization is a method of separation as well as a method of purification.

33. Which of the following results in formation of new substance?

1. Physical change
2. Chemical change
3. Both a and b
4. None

Explanation

Changes that occur with the formation of new substance with different chemical composition or transformation of a substance into another substance with the evolution or absorption of heat or light energy are termed as chemical changes.

34. Which of the following are examples of chemical change?

1. Curdling of milk
2. Burning
3. Fermentation
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Chemical changes are very important in our lives. All the new substances which we use in various fields of our life are produced as a result of chemical reactions. Some of the examples of the importance of chemical changes are given below: Rusting of iron, burning, curdling of milk, reaction of baking soda with lemon juice, fermentation are some examples of chemical changes.

35. Which of the following are accompanied by chemical changes?

1. Heat
2. Sound
3. Gas
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

In addition to new products, the following may also accompany a chemical change:

• Heat, light or any other radiation may be given off or absorbed.
• Sound may be produced
• A change in smell may take place (or) a new smell may be given off.
• A colour change may take place.
• A gas may be formed.

36. Explosion of a firework is a________

1. Physical change
2. Chemical change
3. Either a or b
4. None

Explanation

Explosion of a firework is a chemical change. We know that such an explosion produces heat, light, sound and unpleasant gases that pollute the atmosphere. That is why we are advised not to play with fireworks.

37. When slice of apple is kept in air, it becomes_____ in colour

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

Explanation

You must have noticed that a slice of an apple acquires a brown colour if it is not consumed immediately. Colour of the potato remains the same when stored in water but there is change in colour with the piece kept in air. Look at the cut brinjal kept in air.

38. The iron pillar which has not been rusted is located in________

1. Agra
2. Delhi
3. Chennai
4. Vijayanagar

Explanation

There is an iron pillar at the Qutub complex in Delhi which is more than 1600 years age. Even after such a long period, the iron pillar kept in open spaces has not rusted at all. This shows that Indian scientists made great advances in metal making technology even at 16th century which enabled them to make this iron pillar having the quality of great rust resistance.

39. iron +___ +____ →rust

1. CO2, Water
2. O2, Water
3. SO2, Water
4. NO2, Water

Explanation

iron + oxygen + water →rust

2Fe + 2O2 from air + 2H2O 2Fe2O3. H2O

40. Which of the following can be used for galvanization?

1. Zinc
2. Iron
3. Helium
4. Chromium
5. 1, 2, 4
6. 2, 3, 4
7. 1, 2, 3
8. All the above

Explanation

Another way of preventing rusting is to deposit a layer of a metal like chromium or zinc on iron. This is called galvanization. Iron articles can be prevented from making contact with oxygen, water/water vapour. A simple way is to apply a coat of paint or grease. These coats should be applied regularly to prevent rusting.

41. Which of the following substances are formed during burning a paper?

1. NO2
2. carbon-dioxide
3. water vapour
4. Smoke
5. 1, 2, 3
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

Burning a piece of paper gives entirely new substances such as carbon-dioxide, water, water vapour, smoke and ash. Heat and light are also given out during the burning of paper. We cannot combine the products of burning of paper to form the original paper again. So, it is a permanent change.

42. When magnesium ribbon is burnt it produce_______ coloured light

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

Explanation

You can see that the magnesium ribbon starts burning with a dazzling white light. Hold the burning magnesium ribbon over a watch glass so that the powdery ash being formed by the burning of magnesium collects in the watch glass.

43. 2Mg + O2 🡪

1. MgO2
2. Mg2O
3. 2MgO
4. 2MnO

Explanation

When magnesium ribbon burns in air, then the magnesium metal combines with the oxygen of air to form a new substance called magnesium oxide.

Magnesium + Oxygen 🡪Magnesium oxide

2Mg + O2 🡪2MgO

44. Which of the following statement is correct?

1. Curdling is a process in which liquid gradually turns into solid, forming clumps along the way.
2. It is a Physical change
3. Curdling of milk is an example of irreversible change
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

We know that curdling of milk is an example of irreversible change since we cannot get back the milk after curdling occurs. It is also called as a chemical change. Curdling is a process in which liquid gradually turns into solid, forming clumps along the way.

45. Which of the following breaks the sugar solution into alcohol and carbon-di-oxide?

1. Virus
2. Fungi
3. Yeast
4. None

Explanation

Fermentation is the process in which microorganisms such as yeast and certain bacteria break down sugar solution into alcohol and carbon-di-oxide. It is an irreversible process as the alcohol formed cannot be turned back into sugar

46. Who was the first person to describe the process of fermentation?

1. Louis Pasteur
2. Robert Koch
3. Edward Jenner
4. Edward patison

Explanation

Louis Pasteur (1822- 1895), a French chemist and microbiologist was the first person to describe the process of fermentation.

47. Who discovered the cure for rabies?

1. Louis Pasteur
2. Robert Koch
3. Edward Jenner
4. Edward patison

Explanation

Louis Pasteur described that fermentation occurs in the absence of air and in the presence of micro-organisms such as yeast. He discovered the cure for rabies.

48. Which of the following is formed when Baking soda is mixed with lemon juice?

1. Sodium citrate
2. Carbon di-oxide
3. Carbon Mono-oxide
4. Water
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

Baking soda is sodium hydrogen carbonate and lemon juice contains citric acid. So, when these two substances are mixed together, then a chemical change takes place between sodium hydrogen carbonate and citric acid to form three new substances: sodium citrate, carbon di-oxide and water.

49. Assertion(A): When lemon juice is mixed with soda water, they produce brisk effervescence

Reason(R): Change in pressure may also bring about a chemical change

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

We know that firing of crackers is a chemical change. Some crackers explode only when thrown against a wall or struck with a hard substance. Thus, we could see that change in pressure may also bring about a chemical change. When lemon juice is mixed with soda water, they produce brisk effervescence which is otherwise not possible when they are separate.

50. Assertion(A): yeast acts as the catalyst in the fermentation of sugar

Reason(R): Catalysts are substances that speed up the process of a chemical change and it will not undergo any change during the course of 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

Catalysts are substances that speed up the process of a chemical change and it will not undergo any change during the course of the reaction. For example, yeast acts as the catalyst in the fermentation of sugar. You will learn more about catalyst in your higher classes.

51. Burning of wood is an example of_______ change

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

Explanation

We saw that the burning of magnesium ribbon gives out heat and light. Similarly, burning of wood also releases heat and light. Such changes in which heat is released are known as exothermic changes.

52. Dissolution of glucose in water is________ change

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

Explanation

There are some changes in which heat is absorbed. For example, water absorbs heat when it evaporates to form water vapours. Similarly, ice absorbs heat when it melts to form water. Such changes in which heat is absorbed are known as endothermic changes. Dissolution of glucose in water is also an endothermic change.

53. Which of the following are periodic change?

1. Motion of the seconds-hand
2. Rotation of earth
3. Beating of the heart
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Changes that repeat themselves after a definite interval of time are called periodic changes. Rotation and Revolution of earth, beating of the heart, clock striking every hour, motion of the seconds-hand / minute-hand / hour-hand of a clock are some examples of periodic changes.

54. Which of the following are Non-periodic changes?

1. Eruption of a volcano
2. Streak of lighting flash across the sky
3. Seasonal change
4. 1, 3
5. 2, 3
6. 1, 2
7. All the above

Explanation

Changes that do not repeat themselves after a definite interval of time and occur randomly are called non-periodic changes. Eruption of a volcano, occurrence of an earthquake, a streak of lighting flash across the sky during a thunderstorm, running of a batsman between the wickets, movement of legs while dancing are a few examples of non-periodic changes.

7th Science Lesson 10 Questions in English

10] Cell Biology

1. Salmonella species is a_____

1. Virus
2. Fungus
3. Bacteria
4. None

Explanation

Bacteria are micro-organisms that can be seen only under microscope and not seen through naked eyes. Salmonella species is a Bacteria that can cause food-borne infection.

2. The basic functional unit of an organism is called____

1. Nucleus
2. Cell
3. Axon
4. Slime

Explanation

The basic functional unit of an organism is called, a cell. Structure of a cell represent the arrangement of parts or organelles in a cell. Function is the activity of each part or organelle in a cell. Cells are the basic building blocks of an organism.

3. Which of the following statement is correct?

1. Some simple organisms, are made up of only one cell, called as unicellular organisms
2. They can be seen with naked eyes
3. There are many single – celled microscopic organisms.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Some simple organisms, are made up of only one cell. They are called unicellular organisms, which can be seen with the help of a microscope. There are many single – celled microscopic organisms.

4. Which of the following are single cell organisms?

1. Amoeba
2. Chlamydomonas
3. Bacteria
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Chlamydomonas and an Amoeba, a single-celled organism which carryout entire functions. The body of all organisms are made up of tiny building blocks called, cells. Bacteria are also one celled unicellular organism.

5. Arrange the following in order:

1. Organ
2. Organ system
3. Cell
4. Tissue
5. 4, 1, 2, 3
6. 2, 1, 4, 3
7. 3, 4, 1, 2
8. 3, 2, 1, 4

Explanation

The cells are organized into tissues, organs and organ systems in a multicellular organism. Macroscopic organisms are visible and consists of many cells. The body of macroscopic organisms involves various functions.

6. Which of the following are organ systems?

1. Respiratory system
2. Excretory system
3. Digestive system
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Many cells function together to form tissues, different tissues combined together to form an organ and different organs to form an organ system, which leads to form an organ. Many types of organ systems function together in a body, e.g. respiratory system, digestive system, excretory system, circulatory system etc.

7. Which of the following is not included in respiratory system?

1. Nostrils
2. Nasal chamber
3. Liver
4. Wind pipe

Explanation

Many organs together form an organ system, which is concerned with a specific function. For example, Respiratory system, which has organs like nostrils, nasal chamber, wind pipe and lungs that helps in the process of respiration.

8. Which of the following does the function of conduction of water, mineral and also fixation?

1. Primary roots
2. Secondary roots
3. Tertiary roots
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

In a plant, the root system consists of primary root, secondary root and tertiary root, which does the function of conduction of water, mineral and also fixation.

9. Which of the following is odd on related to plants?

1. Stomach
2. Roots
3. Leaves
4. Stem

Explanation

A collection of different tissues worked together to perform a specific function or functions is called an organ. Human body has different organs like stomach, eye, heart, lungs etc., are made up of different type of tissues. Plants have organs such as leaves, stems, and roots.

10. Which of the following statement is correct?

1. Tissue is a group of cells, organized for a specific function.
2. Human and other animals are made up of nervous, epithelial, connective and muscle tissues.
3. Plants have transport, protective and ground tissues.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Tissue is a group of cells, organized for a specific function. Tissues have following features like same shaped cells or different shaped cells to perform a common function. Human and other animals are made up of nervous, epithelial, connective and muscle tissues. Plants have transport, protective and ground tissues.

11. Assertion(A): Our body is made up of many different kinds of cells.

Reason(R): Each type of cell is specialized to perform a specific function.

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

Our body is made up of many different kinds of cells. Each type of cell is specialized to perform a specific function. Depending on the function, cell has specific shape, size and may have some components which other type of cells do not have.

12. Which of the following statement is incorrect?

1. Inside a cell, there are many tiny structures called cell organelles
2. They work to bring in food supplies, get rid of waste, protection and repair of the cell, and help it to grow and reproduce.
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Inside a cell, there are many tiny structures called cell organelles. These organelles are responsible for providing needs of the cell. They work to bring in food supplies, get rid of waste, protection and repair of the cell, and help it to grow and reproduce. Each one has a specific function to do for the cell.

13. Which of the following is not found in Prokaryotes?

1. Cell membrane
2. Cytoplasm
3. Nucleus
4. All the above

Explanation

As we have mentioned before, all cells have some common structure.

These are 1. Cell membrane 2. Cytoplasm, and 3. Nucleus (In most eukaryotic cells)

Nucleus not found in prokaryotes.

14. The boundary of an animal cell is_____

1. Nucleus
2. Cytoplasm
3. Protoplasm
4. Plasma membrane

Explanation

The boundary of an animal cell is the plasma membrane, which is also called as cell membrane. All animal and plant cells are enclosed or surrounded by a cell membrane.

15. Which of the following statement is correct?

1. Animal cells often have an irregular shape
2. Plant cells have a much more regular and rigid shape
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

All animal and plant cells are enclosed or surrounded by a cell membrane as you learned before. However, as you might have noticed previously that, animal cells often have an irregular shape, whereas plant cells have a much more regular and rigid shape.

16. What is the function of cell wall in plants?

1. Support
2. Conduction
3. Stability
4. Both 1 and 3

Explanation

Plant cells have an additional layer on the outer side of the cell membrane. This is called as the cell wall, that provides a frame work for support and stability

17. Which of the following statement is correct?

1. The cell wall is formed from various compounds, the main one being cellulose.
2. Cellulose allows the plant to remain rigid and upright even if it grows to great heights
3. Each cell is interconnected with its neighbouring cells through openings called Plasmodesmata.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The cell wall is formed from various compounds, the main one being cellulose. Cellulose helps to maintain the shape of the plant cell. This allows the plant to remain rigid and upright even if it grows to great heights. Each cell is interconnected with its neighbouring cells through openings called Plasmodesmata.

18. Which of the following statement is incorrect?

1. Chloroplast is responsible for photosynthesis
2. Vacuoles are filled with both organic and inorganic molecules
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

19. Which of the following is involved in the development of spindle fibres?

1. Nucleus
2. Centrioles
3. Cytoplasm
4. Golgi body

Explanation

20. Which of the following is the control centre of the cell?

1. Golgi body
2. Mitochondria
3. Cytoplasm
4. Nucleus

Explanation

21. Which of the following is contained in Ribosome?

1. DNA
2. RNA
3. Either a or b
4. Both a and b

Explanation

22. Which of the following is not included in cytoplasm?

1. Nucleus
2. Ribosomes
3. Mitochondria
4. Endoplasmic reticulum

Explanation

23. Which of the following is involved in protein and lipid synthesis?

1. Nucleus
2. Endoplasmic reticulum
3. Mitochondria
4. Golgi body

Explanation

24. Which of the following makes ATP?

1. Nucleus
2. Endoplasmic reticulum
3. Mitochondria
4. Golgi body

Explanation

25. What is the shape of Epithelial cells?

1. Cylindrical
2. Flat
3. Circular
4. Oval

Explanation

26. __________ are specialized to carry and conduct messages that coordinate the functions of the body

1. Epithelial cells
2. Muscle cells
3. Nerve cells
4. RBC

Explanation

27. What is the shape of RBC?

1. Round
2. Rectangular
3. Disc
4. Biconcave
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

28. Assertion(A): Stem Cells are utilized by the Scientist and Medicos, to cure and prevent some diseases like Spinal cord injury

Reason(R): Stem cells are quite amazing as they can divide and multiply while at the same time

with their ability to develop into any other type of cell

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

Stem cells are quite amazing as they can divide and multiply while at the same time with their ability to develop into any other type of cell. Embryonic stem cells are very special as they can become absolutely any type of cell in the body, for example, blood cell, nerve cell, muscle cell or gland cell. So, they are utilized by the Scientist and Medicos, to cure and prevent some diseases like Spinal cord injury .

29. What % of water in cytosol?

1. 70 to 90
2. 30 to 50
3. 40 to 60
4. 15 to 20

Explanation

The cytoplasm includes all living parts of the cell with in the cell membrane, excluding the nucleus. The cytoplasm is made up of the cytosol and cell organelles. The cytosol is a watery, jellylike medium made up of 70% – 90% water and usually colourless.

30. Which of the following are included in cell?

1. Vacuole
2. Chloroplast
3. Mitochondria
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Cell organelles and structures present in a cell are endoplasmic reticulum, vacuole, ribosome, golgi body, lysosome, mitochondria, centriole, chloroplast, surrounded by plasma membrane and cell wall.

31. The material inside and outside the nuclear membrane is known as_____

1. Endoplasmic reticulum
2. Cytoplasm
3. Protoplasm
4. Nucleoplasm

Explanation

In particular, the material inside and outside the nuclear membrane is known as Protoplasm. The fluid inside the nucleus is known as the nuclear fluid or nucleoplasm and outside the nucleus is called as cytoplasm.

32. Which of the following statement is correct?

1. Anaerobic respiratory reactions take place with-in the mitochondrion to release energy
2. Mitochondria is an oval or rod-shaped double membrane bounded organelle.
3. It is known as “the Power House” of the cell
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mitochondria is an oval or rod-shaped double membrane bounded organelle. Aerobic respiratory reactions take place with-in the mitochondrion to release energy. So, it is known as “the Power House” of the cell. The energy produced within the mitochondrion is used for all the metabolic activities of the cell.

33. Which of the following statement is correct?

1. Chloroplasts are the only cell organelles that can produce food from the sun energy
2. Chlorophyll can absorb radiant energy from the Sun and convert it to the chemical energy which can be used by the plants and animals
3. Animal cells have chloroplasts and but are unable to do photosynthesis
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Chloroplasts are the only cell organelles that can produce food from the sun energy. Only plants with chloroplast are able to do photosynthesis because they contain the very important green pigment, chlorophyll. Chlorophyll can absorb radiant energy from the Sun and convert it to the chemical energy which can be used by the plants and animals. Animal cells lack chloroplasts and are unable to do photosynthesis.

34. As fruits ripen, chloroplasts change to_________

1. Sulphur
2. Nitrogen
3. Chromoplasts
4. Chromium

Explanation

Various range of these plastids impart different colours to various parts of plant. Chromoplast impart colour to flower and fruits. As fruits ripen, chloroplasts change to chromoplasts. Starch is converted to sugar.

35. Which of the following are the functions of Golgi Complex?

1. Production of secretory substances
2. Packaging
3. Secretion
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Membrane bounded sacs are stacked on top of the other with associated secretory vesicles are collectively known as Golgi complex. Functions of Golgi complex are the production of secretory substances, packaging and secretion. This is the secret behind the change in the colour and taste of fruits.

36. Which of the following is known as Suicidal Bag?

1. Nucleus
2. Lysosome
3. Centrioles
4. Leucoplasm

Explanation

Lysosome- “Suicidal Bag”

Everything I touch, I destroy You will find organelles called as lysosomes, which are very small to view using a light microscope. They are the main digestive compartments of the cell. They lyse a cell, hence they are called “suicidal bag”

37. Which of the following is present in animals and absent in plants?

1. Endoplasmic reticulum
2. Nucleus
3. Centrioles
4. Lysosomes

Explanation

Centrioles are generally found close to the nucleus and are made up of tube-like structures. Centrioles or centrosomes are present only in animal cells and absent in plant cells. It helps in the separation of chromosomes during cell division.

38. Which of the following helps in synthesis of protein?

1. Rough endoplasmic reticulum
2. Smooth endoplasmic reticulum
3. Centrioles
4. Both a and b

Explanation

Rough endoplasmic reticulum is rough due to the ribosomes attached to the membrane. which helps in the synthesis of protein

Smooth endoplasmic reticulum. It is a network of tubular sacs without ribosomes on the membrane. They play a role in the synthesis of lipids, steroids and also transport them within the cell.

39. Which of the following statement is correct?

1. Plant and animal cells have a nucleus inside the cytoplasm
2. During cell division, the chromatin body is organised into a chromosome.
3. One or two nucleolus and the chromatin body are present inside the nucleus
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Plant and animal cells have a nucleus inside the cytoplasm. It is surrounded by a nuclear envelope. One or two nucleolus and the chromatin body are present inside the nucleus. During cell division, the chromatin body is organised into a chromosome. Storage of genetic material and transfers heredity characters from generation to generation are the functions of chromosome.

7th Science Lesson 11 Questions in English

11] Basis of Classification

1. ______ number of species of living organisms have been identified and named till now

1. 8.7 billion
2. 8.7 million
3. 8.7 lakhs
4. 10 billion

Explanation

We see various plants and animals around us. It is estimated that about 8.7 million species of living organisms have been identified and named till now.

2. Which of the following statement is incorrect?

1. In order to know about the behaviour and relationship among organisms, that are known, biologists have classified them into two broad groups, plants and animals
2. Grouping of living organisms based on their common features is known as biological classification
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Many scientists believe that, only a small portion of the total species existing on earth has been identified. In order to know about the behaviour and relationship among organisms, that are known, biologists have classified them into two broad groups, plants and animals. Grouping of living organisms based on their common features is known as biological classification.

3. Classification of living organisms is based on_____

1. Characteristics
2. Similarities
3. Differences
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Living organisms are so large in number that they need to be classified into smaller groups. Classification of living organisms is made on the basis of their characteristics, similarities and differences.

4. Match the following:

1. Warm – Blooded 1. Reptiles
2. Cold- Blooded 2. Birds
3. With Jointed Legs 3. Worm
4. Without Legs 4. With 3 pairs of leg
5. 4, 1, 2, 3
6. 1, 2, 4, 3
7. 2, 1, 4, 3
8. 2, 4, 1, 3

Explanation

5. Who classified animals into those ‘with blood’ and those ‘without blood’ before 2400 years?

1. Panini
2. Aristotle
3. Darwin
4. Pliny the elder

Explanation

Aristotle was a Greek philosopher and thinker who lived about 2400 years ago.

• He classified all organisms into either animals or plants
• Then he classified into those ‘with blood’ and those ‘without blood’.
• Then the animals are classified into three groups based on their method of movement: walkers, flyers or swimmers.

6. Which of the following about necessity of classification is correct?

1. Classifying things makes it easy for us to know their similarities and differences
2. Classification helps us to understand, living and non – living things in better way
3. Things with similar characters are classified into same group
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Why do we classify things?

1. Classifying things makes it easy for us to know their similarities and differences.

2. Things with similar characters are classified into same group. These things are usually similar in at least one characteristic.

3. Things with different characteristics are classified into different groups. These things are usually different in at least one characteristic.

4. Classification helps us to understand, living and non – living things in better way. For example, we can classify a newly discovered organism, we would come to know, how it relates with other.

7. Who introduced the hierarchy of categories?

1. Ernest Heackel
2. Ernest Rutherford
3. Carl Linnaeus
4. R.H. Whitaker

Explanation

The system of arranging taxonomic categories in a descending order based on their relationships with other group of organisms is called hierarchy of categories”. This system was introduced by Linnaeus and is called Linnaean hierarchy.

8. Which of the following is the basic unit of classification

1. Class
2. Order
3. Species
4. Genus

Explanation

There are seven main categories of hierarchies namely, Kingdom, Phylum, Class, Order, Family, Genus and Species. Species is the basic unit of classification

9. Which of the following are examples of Protozoa?

1. Amoeba
2. Euglena
3. Paramoecium
4. All the above

Explanation

10. Multicellular organisms with holes in the body are called as_____

1. Coelenterata
2. Aschelminthes
3. Nematoda
4. Porifera

Explanation

11. Which of the following belong to phylum Coelenterata?

1. Ascaris lumbricoides
2. Hydra
3. Planaria
4. Nereis

Explanation

12. Which of the following is/are hermaphrodite?

1. Planaria
2. Tapeworm
3. Blood fluke
4. All the above

Explanation

13. Which of the following phylum is also known as Nematoda?

1. Aschelminthes
2. Platyhelminthes
3. Annelida
4. Porifera

Explanation

14. Which of the following are included in Phylum Annelida?

1. Earthworm
2. Tapeworm
3. Corals
4. Roundworm

Explanation

15. Which of the following has thick chitinous cuticle?

1. Crab
2. Lizard
3. Scorpion
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

16. Which of the following is not characteristics of Mollusca?

1. Soft bodied
2. Unsegmented
3. Hermaphrodite
4. Calcareous shell

Explanation

17. Exclusively marine, spines and spicules over the body are the features of_____

1. Arthropoda
2. Pisces
3. Amphibia
4. Echinodermata

Explanation

18. Which of the following belongs to Class Pisces?

1. Shark
2. Catla
3. Blue whale
4. Tilapia
5. 1, 2, 4
6. 2, 3, 4
7. 1, 3, 4
8. All the above

Explanation

19. Which of the following statement about Amphibia is correct?

1. Cold- blooded
2. Three pairs of limbs
3. Sexual reproduction
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

20. Which of the following does not belongs to Reptilia?

1. Garden lizard
2. Toad
3. Turtles
4. Tortoise

Explanation

21. Which of the following statement about Aves is correct?

1. Powerful eyes
2. Viviparous
3. Spongy bones with air cavities
4. 1, 2
5. 2, 3
6. 1, 3
7. All the above

Explanation

22. Which of the following does not belongs Class Mammalia?

1. Kangaroo
2. Man
3. Snakes
4. Dog

Explanation

23. Which of the following statement is correct?

1. Based on dichotomy, plants also can be classified into two main groups
2. Flowering plants do not produce seeds
3. Non – flowering plants produce seeds
4. 1, 2
5. 1 alone
6. 2, 3
7. All the above

Explanation

Based on dichotomy, plants also can be classified into two main groups – Flowering and Non – flowering. Non – flowering plants do not produce seeds and flowering plants produce seeds.

24. Based on their nature of plant body, non – flowering plants are classified into______ types

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

Explanation

Based on their nature of plant body, non – flowering plants are classified into three types: algae, mosses and ferns.

25. Based on what flowering plants are classified into gymnosperms and angiosperms?

1. Fruit colour
2. Fruit body
3. Flower colour
4. Plant structure

Explanation

Based on their fruit body, flowering plants are classified into two types: gymnosperms and angiosperms.

26. Which of the following statement about Algae is correct?

1. Plant is thallus, not well-differentiated into root, stem, and leaves
2. They are predominantly aquatic
3. They are unicellular or multicellular – filamentous
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Algae:

• Plant is thallus, not well-differentiated into root, stem, and leaves
• They are predominantly aquatic.
• They are unicellular or multicellular – filamentous. Example – Chara

27. Match the following:

1. Has no true roots, stems or leaf 1. Conifers
2. Has some roots, stems and leaves 2. Tamarind

like structures

1. Gymnosperms 3. Mosses
2. Angiosperms 4. Algae
3. 4, 3, 1, 2
4. 3, 4, 1, 2
5. 3, 1, 2, 4
6. 3, 4, 2, 1

Explanation

28. Match the following

1. Reptiles 1. Octopus
2. Worm 2. Flatworm
3. Amphibians 3. Salamander
4. Mollusca 4. Crocodile
5. 2, 1, 3, 4
6. 4, 1, 2, 3
7. 4, 2, 3, 1
8. 1, 2, 4, 3

Explanation

29. Which of the following statement about mosses is correct?

1. Plant body is differentiated into true root, stem and leaves.
2. They do not have any specialized vascular tissues for conduction of water and food
3. Funaria is an example of mosses
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Mosses

• Plant body is not differentiated into true root, stem and leaves.
• They are water living plants, needs moisture to complete its life cycle. Hence, they are referred to as amphibious plants
• They do not have any specialized vascular tissues for conduction of water and food. Examples: Funaria

30. Which of the following statement about ferns is correct?

1. Plant body is well-differentiated into root, stem, and leaves.
2. Leaves may be large or small
3. Basically, they are the first land plants which grows well in shady, moist, and cool places
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Ferns

• Plant body is well-differentiated into root, stem, and leaves. Leaves may be large or small.
• Specialized vascular tissues are found for the conduction of water and food.
• Basically, they are the first land plants which grows well in shady, moist, and cool places. (Examples: Adiantum)

31. Which of the following statement about Gymnosperms is correct?

1. Plants are perennial, woody, evergreen with true root, stem and leaves
2. They possess vascular tissues, xylem without vessels and phloem with companion cells.
3. Seeds are naked.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Gymnosperms

• Plants are perennial, woody, evergreen with true root, stem and leaves.
• They possess vascular tissues, xylem without vessels and phloem without companion cells.
• Ovules are naked, without ovary. Hence, they do not produce fruits. Seed are naked. (Examples: Pinus, Cycas)

32. How many whorls does Angiosperms have?

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

Explanation

Angiosperms:

• Plant body is well differentiated into true root, stem, and leaves.
• Angiosperms produce flower with four whorls (calyx, corolla, androecium and gynoecium), hence known as flowering plants.

33. Which of the following statement is correct?

1. Angiosperms are the dominant plant forms of present da
2. Based on the number of cotyledons, angiosperms are broadly divided into two groups
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Angiosperms are the dominant plant forms of present day. Based on the number of cotyledons, angiosperms are broadly divided into two groups. a) monocotyledons b) dicotyledons.

34. Which of the following is matched incorrectly?

1. Monocot – Paddy
2. Dicot – Tamarind
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Plant seeds which have only one cotyledon are said to be monocots. Plant seeds which have two cotyledons are known as dicots. Example– Paddy (monocot), tamarind (dicot)

35. Who proposed the five-kingdom classification?

1. R. H. Whittaker
2. Darwin
3. Carl Linneaues
4. Martin

Explanation

The five-kingdom classification was proposed by R.H. Whittaker in 1969. Five kingdoms were formed on the basis of characteristics such as cell structure, mode of nutrition, source of nutrition and body organization.

36. Bacteria belongs to which kingdom?

1. Monera
2. Protista
3. Plantae
4. Fungi

Explanation

Kingdom Monera – Bacteria:

Most of the bacteria are heterotrophic, but some are autotrophs. Bacteria and Blue green algae are examples for Monera.

37. Assertion (A): All prokaryotes belong to the Kingdom Monera

Reason (R): Cells of prokaryotes do not have a nuclear membrane and any membrane bound

organelles.

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

All prokaryotes belong to the Kingdom Monera, which do not posses true nucleus. Cells of prokaryotes do not have a nuclear membrane and any membrane bound organelles.

38. Which of the following statement is correct?

1. The Kingdom Protista includes unicellular and a few simple multicellular eukaryotes.
2. Animals like protists are often called protozoans
3. They include amoeba and paramecium.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

The Kingdom Protista includes unicellular and a few simple multicellular eukaryotes. There are two main groups of protists. The plant like protists are photosynthetic and are commonly called algae. Algae include unicellular and multicellular types. Animals like protists are often called protozoans. They include amoeba and paramecium

39. Which of the following are included in Kingdom Fungi?

1. Molds
2. Mushrooms
3. Mildews
4. All the above

Explanation

Fungi are eukaryotic, and mostly are multicellular. They secrete enzymes to digest the food and absorb the food after digested by the enzymes. Fungi saprophytes as decomposers (decay –causing organisms) or as parasites. Kingdom Fungi includes molds, mildews, mushrooms and yeast.

40. Which of the following statement is correct?

1. Planatae (plants) are multicellular eukaryotes that carry out photosynthesis.
2. Kingdom Plantae includes ferns, cone bearing plants and flowering plants.
3. Plant cells do not have cell wall
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Planatae (plants) are multicellular eukaryotes that carry out photosynthesis. Reserve food materials are starch and lipids in the form of oil or fat. Plant cells have cell wall and specialized functions, such as photosynthesis, transport of materials and support. Kingdom Plantae includes ferns, cone bearing plants and flowering plants.

41. Which of the following is matched correctly?

1. Vertebrates- Birds
2. Invertebrates – Flatworms
3. 1 alone
4. 2 alone
5. 1, 2
6. None

Explanation

Invertebrates like sponges, hydra, flatworms, round worms, insects, snails, starfishes. Vertebrates like Fish, amphibians, reptiles, birds, and mammals including human beings belong to the kingdom Animalia.

42. Which of the following statement about Animalia is correct?

1. Animalia (animals) are multicellular, eukaryotic and heterotrophic animals
2. Cells have cell wall
3. Most members of the animal kingdom can move from place to place
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Animalia (animals) are multicellular, eukaryotic and heterotrophic animals. Cells have no cell wall. Most members of the animal kingdom can move from place to place.

43. Which of the following about five Kingdom Classification is correct?

1. This system of classification is more scientific and natura
2. It is the most accepted system of modern classification as the different groups of organisms are placed phylogenetically
3. It indicates gradual evolution of complex organisms from simpler one
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Merits of five Kingdom Classification:

• This system of classification is more scientific and natural.
• This system of classification clearly indicates the cellular organization, mode of nutrition, and characters for early evolution of life.
• It is the most accepted system of modern classification as the different groups of organisms are placed phylogenetically. It indicates gradual evolution of complex organisms from simpler one.
• It indicates gradual evolution of complex organisms from simpler one.

44. Who implemented Binomial Nomenclature?

1. R. H. Whittaker
2. Carolus Linnaeas
3. Gaspard Bauhin
4. None

Explanation

Gaspard Bauhin in 1623, introduced naming of organisms with two names which is known as Binomial nomenclature, and it was implemented by Carolus Linnaeas in 1753. He is known as ‘Father of Modern Taxonomy’.

45. Which of the following statement is correct?

1. Binomial nomenclature is a universal system of naming organisms.
2. First is the Genus name, second is the Species name.
3. Genus name begins with a capital letter and Species name begins with a small letter.
4. 1, 2
5. 1, 3
6. 2, 3
7. All the above

Explanation

Binomial nomenclature is a universal system of naming organisms. As per this system, each organism has two names – the first is the Genus name and the second is the Species name. Genus name begins with a capital letter and Species name begins with a small letter.

46. Match the following

1. Human being 1. Rattus rattus
2. Pigeon 2. Homo sapiens
3. Onion 3. Allium sativum
4. Rat 4. Columba livia
5. 4, 1, 2, 3
6. 2, 4, 3, 1
7. 2, 1, 3 4
8. 2, 4, 1, 3

Explanation

47. Match the following

1. Coconut 1. Catla catla
2. Fish 2. Cocos nucifera
3. Ginger 3. Zingiber officinale
4. Date 4. Phoenix dactylifera
5. 2, 1, 3, 4
6. 2, 3, 1, 4
7. 2, 1, 4, 3
8. 1, 4, 2, 3

Explanation

7th Science Lesson 12 Questions in English

12] Light

1. What is the main source of energy for the plants?

a) Light energy

b) Water

c) Soil

d) Atmosphere

Explanation

Light is the only source of energy for plants. So they entirely depend on light.

2. Which is not organic plant based energy for people and animals?

a) Carbohydrates

b) Protein

c) Minerals

d) Fat

Explanation

People and animals derive energy from carbohydrates, protein and fat through their food.

3. Which of these are used to produce energy in photosynthesis?

a) Carbon-di-oxide

b) Sun light

c) Water

d) All the above

Explanation

Plants produce food using the energy from Sun light, carbon-di-oxide and water by the process called as Photosynthesis. Sun light acts a vital role in the process of photosynthesis.

4. Assertion (A): Light sources are objects that can emit light.

Reasoning(R): Sun is the only source of light rays.

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

Objects which are able to emit light are known as light sources. Light rays can come from different sources.

5. How many sources of light are categorized?

a) 3

b) 2

c) 4

d) 1

Explanation

There are two types of sources of light, natural sources of light and artificial sources of light.

6. Assertion (A): The Sun is the primary source of natural light.

Reasoning(R): The natural sources of light emit naturally.

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

Sources which emit light naturally are known as natural sources of light. The Sun is the primary and the major source of natural light.

7. Which of these results in the weak star light?

a) Huge distance from sun

b) Weak luminescence of stars

c) Atmospheric dust

d) All the above

Explanation

Stars also produce light in the same way as the Sun do. However as they are much farther away than the Sun the light from them are too weak.

8. Which of these refers to the ability of living organisms producing light?

a) Bioluminescence

b) Crystalloluminescence

c) Mechanoluminescence

d) Electroluminescence

Explanation

Some living organisms have the ability to produce light named by bioluminescence. It is the effect of certain chemical reactions occurring in the organism.

9. Which of these does not emit light naturally?

a) Jellyfish

b) Glow worm

c) Moon

d) Fireflies

Explanation

Fireflies, jellyfish, glow worm, certain deep sea plants and some microorganisms can emit light naturally.

10. How many artificial light sources are classified?

a) 4

b) 7

c) 3

d) 5

Explanation

The different light sources that are able to produce light artificially can be put under three broad categories.

11. Choose the incorrect statements regarding properties of the moon.

i) It cannot produce light on its own.

ii) The light of sun is reflected by the moon.

iii) The whole part of moon is faced by earth.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The moon provides light as well but it cannot produce light by its own. The light emitted by the Moon is the light of the Sun reflected towards the Earth. When we see the Moon we see only the Moon’s lighted part. Thus half of the moon is always facing the Sun and receiving light from it. Hence, we receive light from the moon.

12. Assertion (A): All the man made light sources is categorized as the artificial sources of light.

Reasoning(R): Neon lamp is an artificial light source.

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

Artificial sources are man – made light sources such as flame of candle, incandescent lamp, neon lamp, Sodium lamp etc.

13. Which of these used to produce light in incandescent sources?

a) High temperature

b) Low pressure

c) High intensity

d) Low energy

Explanation

Incandescent Sources: When certain objects are heated to a high temperature, they begin to emit light. The glowing of hot iron rod is a kind of Incandescent light. Example: Candle, incandescent lamp.

14. Which of these are not related to the gas discharge sources of light?

a) Low pressure gas

b) Electricity

c) Candle

d) Neon lamp

Explanation

Gas Discharge Sources: Passing electricity through certain gases at a very low pressure (discharging) can produce light. Example: Neon lamp, Sodium lamp

15. Which of these is used to excite the gas in a gas discharge lamp?

a) Electric current

b) Pressure variation

c) Sun light

d) Chemical reactions

Explanation

We often use a kind of gas discharge lamp that uses fluorescence to produce visible light. The electric current in the gas excites mercury vapor, which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow in visible light.

16. Which of the following is not a fundamental property of light energy?

a) Reflection

b) Speed

c) Non-transverse

d) Spectrum

Explanation

Light has some fundamental properties which are rectilinear propagation of light, Reflection, Speed, Interaction of light with matter and Spectrum.

17. Which of this property describes the interaction of light with matters?

a) Permeability of materials

b) Shadow formation

c) Plane mirror and images

d) All the above

Explanation

Interaction of light with matter describes the types of material according to permeability, Formation of shadows and Plane mirror and images.

18. What is the most important property of light?

a) Light travels through objects.

b) Light travels faster than sound.

c) Light travels in straight line.

d) Light is the secondary source of energy.

Explanation

Light travels in straight line it cannot bend the path itself. This is called as the rectilinear propagation of light. This is one of the most important properties of light.

19. Which of this light property was experimented by Al-hasan-Haytham?

a) Rectilinear propagation

b) Spectrum

c) Shadow

d) Plane of incidence

Explanation

Al-hasan -Haytham was a scientific thinker who made important contribution to the understanding of vision optics and light. He is the first one to experiment with light and found important properties like the rectilinear propagation of light.

20. Name the type of photography which used the pinhole camera to capture the movement of the sun?

a) Solography

b) Macro photography

c) Motion photography

d) Tilt-shift photography

Explanation

Before the advancement of camera Pinhole camera was used to photograph movement of the sun over a long period of time. This type of photography is known as solography and also be used for observing and recording solar eclipses. And it was also used to take photograph of stationary objects.

21. Which is referred as the light falling on the mirror or surface?

a) Incident ray

b) Direct ray

c) Indirect ray

d) Bundle rays

Explanation

The light falling on the mirror is called as incident ray and the light reflected is called reflected ray.

22. Choose the correct statements.

i) The angle of incidence is always equal to the angle of reflection.

ii) The incident ray and the reflected ray lie on different planes.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Laws of reflection: The angle of incidence is always equal to the angle of reflection. i = r. The incident ray, reflected ray and the normal at the point of incidence lie on the same plane.

23. Which is referred as the angle of reflection?

a) Angle between normal and reflected ray.

b) Angle between incident ray and reflected ray.

c) Angle between Angle of incidence and reflected surface.

d) Angle between Angle of incidence and normal angle.

Explanation

24. Find the angle of incidence for a light ray striking a reflective plane surface at an angle of 72° with the plane surface?

a) 18°

b) 90°

c) 72°

d) 81°

Explanation

Solution: Angle of incidence, i = 90 -72 = 18°

Angle of reflection, r = i = 18°

25. In which of these surfaces the law of reflection is good?

a) Vertical surface

b) Angled surface

c) Curved surface

d) All the above

Explanation

The laws of reflection holds good for all surfaces irrespective of the shape. Vertical surfaces, angled surfaces and even over the curved surfaces, the laws of reflection holds good.

26. On which of this condition the angle of incidence and reflection are equal?

a) Normal is perpendicular to surface.

b) Surface is smoother.

c) Reflective surface is mirror.

d) None of the above

Explanation

As long as we can draw the normal perpendicular to the surface at the point can be drawn the angle of incidence at that point will be equal to angle of reflection.

27. Choose the correct statements.

i) The surface orientation influences the law of reflection.

ii) Smooth surfaces have normal in the same direction at all points.

iii) The parallel rays striking the surface will be reflected at various angles.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The law of reflection is always observed regardless of the orientation of the surface. If the surface is smooth, and flat all points on it have the normal in the same direction. Therefore a set of parallel rays striking the surface will be reflected at an angle but the rays themselves will still remain parallel to each other.

28. How many types of reflection are categorized based on the surface?

a) 2

b) 4

c) 5

d) 3

Explanation

Broadly we can say that there are two types of reflection. If the surface is smooth then we have specular reflection. The parallel light rays striking the surface gets reflected yet individual reflected rays remain parallel.

29. Which of these surface results in diffused reflection?

a) Rough surface

b) Curved surface

c) Smooth surface

d) Plane surface

Explanation

If the surface is rough then we have diffused reflection. Light rays after reflection go in many directions.

30. Assertion (A): Light is a single ray called as a beam of light.

Reasoning(R): A light beam is a bundle of divergent rays.

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

Generally light is not a single ray but a bundle of rays which are called as a beam of light. A light beam can be a bundle of parallel rays’ convergent rays or divergent rays.

31. Choose the Incorrect statements.

i) The Sunlight rays are parallel.

ii) Light rays from a candle are in all directions.

iii) Flash light rays are parallel rays.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The rays of sunlight are parallel. Often the headlight of car gives parallel rays. However look at the rays of light coming out of a candle. Light rays go in all directions, from the candle fire. These rays are divergent. Light rays from a flash light are also divergent.

32. Choose the correct statements.

i) Lenses are used for converging the light rays.

ii) Sunlight cannot be converged by using a lens.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

Using lenses we can converge light rays. Using a lens you can focus sunlight at a point. That is what we are making the light rays to converge.

33. Assertion (A): Light travels faster than the sound.

Reasoning(R): Theoretically nothing can travel faster than light.

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

When lighting a bulb in a dark room light spreads the whole room quickly. This is because the light travels very fast. In theory nothing can travel faster than light.

34. Which of this unit is used to measure the speed of light in air?

a) Kilometer per hour

b) Meter per second

c) Kilometer per second

d) Meter per hour

Explanation

Light travels three lakh kilometers per second in air or vacuum.

35. How many materials are classified based on the permeability?

a) 5

b) 3

c) 7

d) 4

Explanation

Depending upon permeability materials can be classified into three categories.

36. Identify the incorrect Match.

A. Transparent material i) Eye glasses

B. Opaque material ii) Stone

C. Translucent material iii) Card board

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Transparent Material: Eye glasses, clear drinking glass, clear water, face glasses used in buses.

Translucent Material, Opaque Material: Wall, thick card board, stone, etc

37. Which of these statements are not true regarding the concept of shadows?

a) Shadow is caused by the rectilinear property of light.

b) Shadow is always against the opposite side of the light source.

c) Only some of the opaque objects stop light propagation.

d) Shadow consists of both umbra and penumbra.

Explanation

Light travels in a straight line. Hence it cannot go around such objects. That is why we see shadow. Shadow is always against, opposite side of light source. It is caused by opaque objects that stop light from propagating.

38. Assertion (A): The uniform dark shadow of an object appearing on screen is called as umbra.

Reasoning(R): A shadow will be formed when an opaque object is placed in the path of light source.

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

When an opaque object is placed in the path of light from a point source a uniform dark shadow will appear on the screen. This is shadow is called as umbra.

39. Which is the illuminated shadow part of an object placed in the path of light?

a) Penumbra

b) Umbra

c) Darkest part

d) Shadow line

Explanation

When an opaque object is placed in the path of light coming from a broad source of light a small umbra will appear on the screen and an illuminated shadow area appears around umbra. This illuminated shadow area is called as penumbra.

40. Choose the incorrect statements.

i) The Umbra is the darkest part of a shadow.

ii) The umbra always surrounds the penumbra.

iii) Light rays are completely prevented by the opaque object in umbra part.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

The penumbra always surrounds the umbra. The umbra is the darkest part of a shadow. In this part light rays are completely prevented by the opaque object. The lighter shade of shadow is the penumbra.

41. Which of the following does not fall under the properties of shadow?

a) Every object will form shadow.

b) Shadows will be formed in the opposite side of light source.

c) Shadows are always darker.

d) Opaque objects only form shadows.

Explanation

Properties of shadow: All objects do not form shadows. Only opaque objects form shadows. Shadows will be formed in the opposite side of light source. It cannot be determined the characteristics of an object by its shadow. The shadow will be always darker whatever may be the color of light rays.

42. Which of these factors decide the size of the shadow?

a) Distance between light source and object.

b) Intensity of the light source.

c) Color of the light rays.

d) Characteristics of the object.

Explanation

Light source, opaque object are shadow all are in a straight line. The size of shadow depends upon the distance between light source and object and the distance between object and the screen.

43. Assertion (A): Eclipse is an incident when any astronomical object is partially or fully obscured in the presence of light.

Reasoning(R): Solar and lunar eclipse occurs due to the property of rectilinear propagation of light.

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 eclipse is an incident when any astronomical object is partially or fully obscured due to the placement of another astronomical object in the presence of light. Thus solar and lunar eclipses are occurring that are due to the property of light known as the rectilinear propagation of light.

44. Choose the correct statements.

i) Solar eclipse occurs if earth arrives between the moon and the sun.

ii) The shadow of the earth appears on the moon.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

Solar eclipse occurs, when the moon arrives between the sun (S) and the earth (E). The shadow of the moon appears on the earth at A as shown in picture. Hence those who are at the region A are unable to see the Sun instantly. This is solar eclipse.

45. Which of this prevents the light in the lunar eclipse?

a) Moon

b) Earth

c) Sun

d) All the above

Explanation

Lunar eclipse: Lunar eclipse occurs, when the earth (E) comes between the sun (S) and the moon (M). The earth prevents light coming from the sun and makes shadow on the moon. This is lunar eclipse

46. What is the relation between the distance of object (a) and image(b) from the mirror?

a) a > b

b) a < b

c) a = b

d) a + b

Explanation

­The distance of the object from the mirror is equal to the distance of the image from the mirror (a=b).

47. Assertion (A): Optical fiber transmits huge data with negligible loss of energy in short time.

Reasoning(R): Optical fibers works on the total internal reflection of light signals.

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

Optical fiber is a device that works on the principle of total internal reflection by which light signals (huge data) can be transmitted from one place to another place with a negligible loss of energy in a very short time.

48. Assertion (A): Optical fibers can be easily twisted and bent.

Reasoning(R): Optical fibers consist of thin flexible fibers with a glass core.

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

Optical fiber consists of a cable having one or more thin flexible fibers with a glass core through which light signals can be sent. Optical fiber can be twisted and bent easily.

49. Choose the Incorrect statements.

i) Optical fibers are used for high speed communications.

ii) Fiber optics carries fewer signals than traditional copper cable lines.

iii) Cable television and high speed broad band services uses the optical fibers for communication.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Optical fibers have become very important in high-speed communications, such as cable TV and high-speed broadband services. Fiber optic cables are able to carry more signals than traditional copper cable telephone lines.

50. Choose the correct statements.

i) The real image is obtained on a screen.

ii) Virtual image cannot be obtained on a screen.

iii) Image on pinhole camera is upside down.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The images that are obtained on a screen are called ‘real image’ and that which cannot be obtained on a screen ‘virtual image’. The image on pinhole camera was upside down. The mirror image was upright.

51. Which of these properties of image formation is not true for a plane mirror?

a) Image formed is upright.

b) Virtual image is formed in the plane mirror.

c) Image is slightly small than the object.

d) Image is laterally inverted.

Explanation

Properties of Image formed in a plane mirror: Image formed in a plane mirror is upright, Image formed in a plane mirror is virtual, the image is of the same size as the object. The distance of the image from the plane mirror is equal to the distance of the object from the mirror, Image is laterally inverted.

52. Which human part is stimulated by the light energy?

a) Retina

b) Cell

c) Nerves

d) Skin

Explanation

Color of sunlight : Light is a form of energy in the form of a wave that simulates that retina of our eyes.

53. What range of wavelength is represents the visible light spectrum?

a) Nano meter

b) Micro meter

c) Centimeter

d) Millimeter

Explanation

Visible light is a spectrum of a number of waves with different wavelength range from 400nm to 700nm (1nm = 10-9 meter) each wave has a definite wavelength represents a particular color.

54. Which of the following color is not in the band of visible light?

a) Pink

b) Yellow

c) Orange

d) Blue

Explanation

The band of visible light is VIBGYOR.

55. Which of this color has the shortest wavelength?

a) Green

b) Violet

c) Red

d) Magenta

Explanation

Violet color has shorter wavelength and red color has longer wavelength.

56. Choose the correct statements.

i) White is the combination of all the colors of the visible light.

ii) Black color observes all the wavelength of visible light.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

White is not a color at all. But it is the combination of all the colors of the visible light spectrum. If the entire wavelength (colors) of visible light spectrum give appearance of white similarly the observe of all there wavelength of visible light will lead appearance of black.

57. Which of these statements are not true regarding the concept of Prism?

a) Prism is made up of transparent material.

b) It has more than three flat surfaces.

c) The flat surfaces of prism forms an acute angle.

d) Plastic and glass are used to construct a prism.

Explanation

A prism is an object made up of a transparent material like glass or plastic that has at least two flat surfaces that from an acute angle (less than 90 degrees).

58. Why is the word “AMBULANCE” written backwards in ambulance vehicle?

a) Lateral inversion

b) Plane of incidence

c) Total reflection

d) Internal reflection

Explanation

This is due to lateral inversion .The phenomenon due to which the left side of an object appears to be right side of the object in its image in a reflecting medium (mirror) so that drivers see the word the right way around in their rear-view mirror.

59. Choose the Incorrect statements.

i) Real images are formed by the pinhole camera.

ii) The plane mirror images are erected one.

iii) The images formed by the pin hole camera is equal to the size of the object.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Difference between the images formed in Pinhole camera and Plane mirror

60. Assertion (A): Red color can travel a longest distance even through air and fog.

Reasoning(R): Red color has the highest wavelength of all the colors.

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

Red color is scattered the least by air molecules. Red color has the highest wavelength of all the other colors. So, red color is able to travel the longest distance through air, fog.

61. Which of these colors forms a rainbow in a prism?

a) White

b) Red

c) Black

d) Green

Explanation

When white light is passed through a prism as shown in the figure the colors of the rainbow emerge from the prism.

62. Choose the Incorrect statements regarding the Newton Disc.

i) It has seven unequal colored sectors.

ii) Human retina receives the whole disc spectrum simultaneously and disc appears white.

iii) White is a combination of VIBGYOR.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Newton Disc is a card board disc with seven equal sectors colored red, yellow, orange, green, blue, indigo and violet. When the disc turned quickly the retina receives the sensation of the spectrum simultaneously and disc appears white. Using this disc one can explain that white is a combination of VIBGYOR.

63. Which of these is defined as synthesis of color?

a) Creating color by mixing various proportions of colors of light.

b) Differentiating primary and secondary color.

c) Light experiment of various colors.

d) Creating light by various colors.

Explanation

Synthesis of color is the method of creating color by mixing various proportion of two (or) three distinct colors of light.

64. Which of these are categorized as primary colors?

a) Red

b) Green

c) Blue

d) All the above

Explanation

The distinct colors are Red, Green and Blue called as primary colors.

65. Which of these is not a secondary color?

a) Magenta

b) White

c) Cyan

d) Yellow

Explanation

Equal proportions of two primary color create a secondary color. Magenta, Cyan and yellow are called secondary color. Equal proportions of all three primary color create white.

7th Science Lesson 13 Questions in English

13] Universe And Space

1. According to Stephen hawking understanding which of these was his simple goal?

a) Time

b) Space

c) Stars

d) Universe

Explanation

“My goal is simple. It is a complete understanding of the universe, why it is as it is and why it exists at all.”—Stephen Hawking

2. Which of this study is referred to as astronomy?

a) Study of the Universe

b) Study of the Stars

c) Study of the Atmosphere

d) Study of the Galaxies

Explanation

The field of study of the universe is called astronomy.

3. Assertion (A): The Universe is defined as the totality of everything exists or known to exist.

Reasoning(R): It is possible to measure the observable universe.

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

Universe is commonly defined as the totality of everything that exists or is known to exist. Even though the spatial size of the entire universe is still unknown, it is possible to measure the observable universe.

4. Which of these constitutes the universe?

a) Planets

b) Meteorites

c) Galaxies

d) All the above

Explanation

The universe consists of galaxies, planets, stars, meteorites, satellites and all other forms of matter and energy. And it is a world of wonder.

5. In which of these directions the stars tend to rise in earth?

a) West

b) North

c) East

d) South

Explanation

Sky is a wonder. Sun, Moon, stars all appear to rise in the East and move towards the west giving us an impression that all these objects are going around the Earth.

6. Choose the correct statements.

i) The Sun appears to revolve around the earth once in a day.

ii) The Moon and other planets have their own motions.

iii) The celestial sphere appears to rise in the evening and complete its rotation in a year.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The Sun appears to revolve around the Earth once in a day. While the Moon and the planets have their own motions they also appear to revolve around the Earth about once per day. Even the celestial sphere studded with stars appears to rise and set in the evening, and make one complete rotation in a year.

7. What is the perspective of the earth for an earthbound observer?

a) Rotating

b) Revolving

c) Stationary

d) None of the above

Explanation

The Earth seems to be unmoving from the perspective of an earthbound observer, it feels stationary.

8. In how many days the moon appears like going around the earth?

a) One day

b) Fifteen days

c) One month

d) One year

Explanation

On a daily basis Moon appears to rise in the east and set in the west. Thus one can say that Moon is going around the Earth with a period of one day.

9. Choose the correct statements.

i) Moon appears to move from west to east every day.

ii) The Moon goes in a circle motion from west to east for about 27 days.

a) i only

b) ii only

c) Both i and ii

d) None of the above

Explanation

Everyday Moon appears to move from east to west in one day where as it appears to go in a circle from west to east in the background of stars in about 27 days.

10. What is the duration of the actual motion of the celestial sphere in eastward motion?

a) 30 days

b) 15 days

c) 27 days

d) 365 days

Explanation

Astronomers like Aryabhatta said that Earth is spinning in its axis that is the cause of apparent daily motion from East to West. Whereas the eastward motion of Moon in the celestial sphere with a period of about 27 days was seen as the ‘actual’ motion of the celestial objects.

11. Which of these is assumed to be in the center of the geocentric model?

a) Earth

b) Sun

c) Stars

d) Galaxy

Explanation

The geocentric model (also known as geo-centrism), that is a description of the Universe with spherical and spinning Earth at the center and the Sun, Moon, stars, and planets all orbits the Earth emerged in various cultures.

12. Who standardized the geocentric model in 2nd century A.D?

a) Plato

b) Aryabhata

c) Ptolemy

d) Galileo

Explanation

In Greece the geocentric model was put forth by the Greek philosopher Plato and his disciple Aristotle in 6th century B.C. It was standardized by a Greeco-Roman mathematician Ptolemy in the 2nd Century A.D. A similar model is seen in the Siddhanthic astronomy in India like Aryabhateeyam of Aryabhata.

13. Which of this Sangam literature describes the appearance of moon and its movement?

a) Purananuru

b) Silapathikaram

c) Thirukkural

d) Iyngurunooru

Explanation

Astronomers in ancient times also observed certain facts. The Purananuru (65) of Sangam literature, the poet Kalathalaiyar singing in appreciation of Cheraman Peruncheralathan says“ On the day when the full moon appears, the sunand moon look at each other with their bright light. In the evening time, one sphere hides behind the mountains.”

14. On which of this day the Sun and the moon appears to be in opposite sides?

a) New moon day

b) Solstice day

c) Full moon day

d) Equinox day

Explanation

On the full moon day, when the Sun is setting in the west, precisely at the same time Moon rises at the East. That is both Sun and Moon are in the opposite side.

15. Which of these are used to understand the various phases of the Moon?

a) Waxing and Waning

b) Earth revolution

c) Energy from the Sun

d) All the above

Explanation

It is probably easier to understand the waxing and waning of Moon in the order of new moon & full moon and then how the first and third quarter moon (half-moon) appear and then the phases in between.

16. Choose the correct statements.

i) The Sun light falls on the whole spherical part of the earth.

ii) Earth spins day and night and different parts of earth appear before the sun.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

Sun is the source of light. Sun light falls on the spherical earth, but only on the side facing Sun. The opposite side of Earth is without sunlight. As the Earth spins day and night follows as different parts of Earth appear before the Sun. That is at all times one half of Earth is illuminated by Sun and one half is in darkness.

17. In which of this position the new moon appears on the Earth?

a) The Sun is in between earth and the moon.

b) The Earth is in between the moon and the sun.

c) The Sun, Earth and the moon in same line.

d) The Moon is in between the earth and the sun.

Explanation

When the moon is positioned between the earth and sun notice all the illuminated part of Moon is away from Earth. Hence we cannot see any part of the illuminated side of the Moon. Only the dark side of Moon is towards Earth. When the moon is in this position, we have new moon.

18. Choose the Incorrect statements.

i) In the full moon day part of the illuminated moon is towards the earth.

ii) The dark side of the moon is away from the earth in full moon day.

iii) The moon tends to appear in round shape in a full moon day.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The moon when it is behind the Earth. Now the portion of the moon illuminated by sun is totally towards Earth. The dark side is away from the Earth. This means the moon will appear to be round in the sky. This is full moon.

19. When the moon will appear as half-moon in earth?

a) Sun facing the moon.

b) Moon facing the earth

c) Sun facing the earth.

d) Moon facing the sun.

Explanation

When the moon facing Earth half if it illuminated and half is dark side. Thus the moon will appear as half-moon.

20. In which of this period moon is in its third quarter?

a) Waxing

b) Full moon

c) Waning

d) New moon

Explanation

The half-moon during the waxing period is called as first quarter and the half-moon during the waning period is called as third quarter.

21. Which refers to the phase of less than half illuminated moon?

a) Waning

b) Crescent

c) Gibbous

d) Waxing

Explanation

The word crescent refers to the phases where the moon is less than half illuminated.

22. Which of the following phase of moon is referred as gibbous?

a) More than half illuminated moon

b) Full moon

c) Less than half illuminated

d) Expanding illumination

Explanation

The word gibbous refers to phases where the moon is more than half illuminated.

23. Assertion (A): Shrinking or decreasing illumination of the moon is referred as waning.

Reasoning(R): Waxing phase of the moon is referred as growing or expanding illumination.

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

In the phases of the moon waxing essentially means “growing” or expanding in illumination and waning means “shrinking” or decreasing in illumination.

24. Which of these planets motion was not known to the ancient astronomers?

a) Mercury

b) Mars

c) Saturn

d) All the above

Explanation

Moon going around Earth with 27 day period nicely explained its motion. Astronomers in ancient times faced problem in explaining the motion of the then known five planets- Mercury, Venus, Mars, Jupiter and Saturn.

25. Which is known as the retrograde motion of the planets?

a) Reversal direction of planets.

b) Revolving direction of the satellites.

c) Rotation of planets around the sun.

d) Reversal direction of planets and its satellites.

Explanation

On June 28 a change is seen. From that date the Mars would appear to move west rather than its normal eastward motion. This reversal of direction of planets is called as ‘retrograde motion’.

26. Which of this planet will appear brighter in the retrograde motion?

a) Mars

b) Jupiter

c) Moon

d) Saturn

Explanation

Usually Jupiter is brighter than Mars, however around the period of retrograde motion the Mars was much bright than other times; even brighter than Jupiter.

27. Which of these planets never appear in the midnight sky?

a) Moon

b) Mars

c) Mercury

d) Jupiter

Explanation

Venus and Mercury always appeared very close to Sun and hence never appeared in the midnight sky.

28. Assertion (A): The Jupiter varies in its brightness in the retrograde motion.

Reasoning(R): Jupiter moves in the westward motion in the retrograde motion.

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 brightness of Jupiter also varied again when it exhibited retrograde motion. For example in 2018, Jupiter reversed its direction of motion on March 9, 2018 and again resumed its normal eastward motion on July 11, 2018.

29. Which of these are the drawbacks of the geocentric model?

a) Variations in brightness of planets

b) Retrograde motion of planets

c) Revolving time duration of satellites

d) Both a and b

Explanation

The simple geocentric model, where planets go around the Earth could not explain why the brightness of the planets changed, and why they reversed their directions. Change in brightness and retrograde motion would be impossible if we assumed that the planets were at the same distance at all times from Earth.

30. Who used the epicycle model to explain the motion of the celestial objects?

a) Ptolemy

b) Galileo

c) Kepler

d) Copernicus

Explanation

Ptolemy (2nd cent) in Greece Aryabhatta in India and others used the epicycle model to explain the motion of the celestial objects.

31. Who were involved in improving the epicycle model?

a) Neelakanta Somayaji

b) William Herschel

c) Tycho Brahe

d) Both a and c

Explanation

Their models were improved by generation of astronomers like Tycho Brahe and Neelakanta Somayaji.

32. Assertion (A): The Telescope was invented by Hans Lippershey.

Reasoning(R): Galileo was the first person to use the telescope for studying the sky.

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

Telescope was invented by Hans Lippershey but Galileo used it for studying the sky for the first time. The telescope showed more universes were than visible to naked eye.

33. Which of this telescopic observation of planet was made by Galileo?

a) Jupiter

b) Venus

c) Mars

d) Mercury

Explanation

One of the most startling observations Galileo made was related to telescopic observation of Venus. This convinced him to accept the theory of Sun- heliocentric theory. The Polish Astronomer Nicolas Copernicus that it is not Sun, planets and Stars that go around Earth, but it is Earth and other planets that go around the Sun- heliocentric theory.

34. Which of this model was not satisfied for Nicolus Copernicus?

a) Geocentric theory

b) Epicycle model

c) Heliocentric theory

d) All the above

Explanation

Dissatisfied with the messy epicycle model Nicolus Copernicus radically proposed that the model will become simple if we assume Sun is at the center and all planets including Earth go around it.

35. How many days would be taken by Mars to orbit around the Sun?

a) 222 days

b) 365 days

c) 27 days

d) 687 days

Explanation

Earth orbit around Sun in 365 days whereas Mars takes 687 days. This implies at times Earth will overtake Mars. When the Earth is approaching and overtaking Mars, the Mars would appear to exhibit retrograde motion.

36. Choose the correct statements regarding the telescopic observation of Galileo.

i) Venus exhibited various phases like moon.

ii) Only the size of Venus is varied from crescent to gibbous.

iii) The shape of Venus is same in all the phases.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Galileo observed Venus in 1610-1611 with a telescope. To naked eye Venus is just a gleaming bright spot. However, through a telescope, the shape of the planet can be seen. Galilio was startled to find like Moon Venus too exhibited phases. The shape varied from crescent to gibbous. Also, the size of the planet varied. When the planet was in gibbous phase the size was small, and when it was thin crescent the size was many folds higher.

37. Assertion (A): Earth is included in the Milky way galaxy.

Reasoning(R): The Sun is a star with a planetary system.

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

Our Sun is a star with a planetary system. Billions of such stars constitute a system called as galaxy. The name of our galaxy is, Milky Way. Like Milky Way, there are at least hundreds of billions of galaxies in the Universe.

38. According to the scientists which is considered as the origin of the Universe?

a) Big Bang

b) Black hole

c) The Sun

d) Dwarf Stars

Explanation

The Cosmologist’s scientists who study the structure and evolution of universe that is cosmos, reason that this imply at one point of time in the past all matter was confined in a single point and since then it has started to expand. The event when the matter confined in a single point and began to expand is called ‘big bang’. This is considered as the origin of our universe as we know it.

39. Which of these concepts originated by the Big Bang theory?

a) Time

b) Space

c) Matter

d) All the above

Explanation

The Big Bang Theory is the prevailing model of the evolution of the Universe. Under this theory, space and time emerged together about 14 billions of years ago. At that time, the entire Universe was inside a bubble that was thousands of times smaller than a pinhead. It was hotter and denser than anything we can imagine. Then it suddenly expanded. The present Universe emerged .Time, space and matter all began with the Big Bang.

40. Which of this gas were found in the earlier stage of evolution of the universe?

a) Oxygen

b) Helium

c) Hydrogen

d) Both b and c

Explanation

At the stage of the evolution of the Universe, it was filled with clouds of hydrogen and helium gas. Giant clouds of hydrogen and helium were gradually drawn to the places where dark matter was most dense, forming the first galaxies, stars, and everything else seen today.

41. What is the direct evidence for the Big Bang theory?

a) Cosmic microwave background

b) Hydrogen clouds

c) Black holes

d) Dwarf galaxies

Explanation

We cannot see anything that happened during the first 300000 years of the Universe. Scientists try to work it out from their knowledge of atomic particles and from computer models. The only direct evidence of the Big Bang itself is a faint glow in space, called cosmic microwave background.

42. After how many years after the Big Bang the first star was formed?

a) 100 million years

b) 250 light years

c) 100,000 million years

d) 200 trillion years

Explanation

Finally, about 100 million years after the Big Bang, the gas became hot and dense enough for the first stars to form. New stars were being born at a rate 10 times higher than in the present-day Universe. Large clusters of stars soon became the first galaxies.

43. What are the building blocks of the Universe?

a) Stars

b) Asteroids

c) Meteors

d) All the above

Explanation

The Universe is constituted of galaxies; just as lot of houses in our locality constitute a village or a city. We have lot of things such as rooms, furniture etc. in our homes. Likewise lot of stellar objects such as stars, planets, asteroids and meteors are the building blocks of our universe.

44. Identify the Incorrect Match.

A. One au i) 1.496 x 10⁸ km

B. One pc ii) 3.258 x 10²⁴ km

C. One ly iii) 9.4607 x 10¹²km

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Astronomical unit: The average distance between the Earth and the Sun is called an astronomical unit. It is denoted by ‘au’. 1 au = 1.496 x 10⁸km

Light year: The distance travelled by light in one year is called a light year. It is denoted by ‘ly’. 1 ly = 9.4607 x 10¹² km

Parsec: A parsec is defined as the distance at which one astronomical unit subtends an angle of one arc second. It is denoted by ‘pc’

1 pc = 3.2615 ly = 3.09 x 10¹³ km

45. Which of these constitutes a galaxy?

a) Collection of stars

b) Cluster of stars

c) Celestial bodies

d) All the above

Explanation

A galaxy is a large collection of stars or cluster of stars and celestial bodies held together by gravitational attraction. There are about billions of galaxies in the universe. Most galaxies range from thousand to ten thousand parsec in diameter.

46. How many types of galaxies are classified so far?

a) 5

b) 4

c) 6

d) 2

Explanation

Types of galaxies: There are various types of galaxies such as spiral, elliptical, barred spiral and irregular.

47. Which of this galaxy have the bulge or central concentration of stars?

a) Spiral galaxy

b) Elliptical galaxy

c) Barred spiral galaxy

d) Irregular galaxy

Explanation

Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. These are often surrounded by a much fainter halo of stars. Spiral galaxies are named by their spiral structures that extend from the center into the galactic disc. The spiral arms are sites of ongoing star formation and are brighter than the surrounding disc because of the young, hot stars that inhabit them.

48. Which of these is not a property of an elliptical galaxy?

a) Elliptical galaxies are three dimensional.

b) The stars are random orbits around the center of an elliptical galaxy.

c) Stars of spiral galaxies are much older than elliptical galaxies.

d) Elliptical galaxies are surrounded by large number of globular clusters.

Explanation

An elliptical galaxy is a type of galaxy having an approximately ellipsoidal shape and a smooth image. Unlike flat spiral galaxies with organization and structure, elliptical galaxies are three-dimensional, without much structure and their stars are in somewhat random orbits around the center. Interestingly Stars found inside of elliptical galaxies are on an average much older than stars found in spiral galaxies. Elliptical galaxies tend to be surrounded by large numbers of globular clusters.

49. Choose the incorrect statements about the Irregular galaxies.

i) It does not have a regular shape and chaotic in appearance.

ii) It contains abundant amount of gas and dust.

iii) About two third of the galaxies are of this type.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure. About one-fourth of the galaxies found so far are of this type. Irregular galaxies may contain abundant amounts of gas and dust.

50. Assertion (A): The Irregular galaxies were once spiral or elliptical galaxies.

Reasoning(R): The Uneven external gravitational forces deform the galaxies and make them irregular.

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

Cosmologists say that some irregular galaxies were once spiral or elliptical galaxies but were deformed by an uneven external gravitational force.

51. Under which of this type of galaxy the Milky Way is categorized?

a) Barred Spiral galaxy

b) Elliptical galaxy

c) Spiral galaxy

d) Irregular galaxy

Explanation

The Milky Way Galaxy where our own Solar System is located is classified as a barred spiral galaxy.

52. What is the diameter of the Milky Way?

a) 100,000 light years

b) 100 light years

c) 1000 light years

d) 10000 light years

Explanation

The Milky Way is the galaxy in which our solar system is located. The diameter of Milky Way is over 100,000 light years.

53. Which of these are included in the Milky way?

a) Celestial bodies

b) Dead stars

c) Clouds of Dust

d) All the above

Explanation

The Milky Way includes stars smaller than our Sun as well as many other stars that are thousands of times bigger than the Sun. It includes many other celestial bodies of gases, clouds of dust, dead stars, newly born stars, etc. It is also thought to contain at least 100 billion stars.

54. Which of these galaxies is the closest to the Milky Way?

a) Cygnus

b) Virgo

c) Andromeda

d) Magellan Clouds

Explanation

The galaxy that is closest to our Milky Way is Andromeda. The descriptive “milky” is derived from the appearance from Earth of the galaxy – a band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye.

55. Who resolved the band of light into individual stars in the year 1610?

a) Galileo Galili

b) Johannes Kepler

c) Nicolaus Copernicus

d) Tyco Brahe

Explanation

Galileo Galili first resolved the band of light into individual stars with his telescope in 1610.

56. Who proved that the Milky way is just one of many galaxies?

a) Dan Lewis

b) Giovanni Cassini

c) Edwin Hubble

d) Christiaan Huygens

Explanation

Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Observations by Edwin Hubble showed that the Milky Way is just one of many galaxies.

57. How long the solar system will take to travel along the Milky Way?

a) 230 million years

b) 100000 light years

c) 250 Astronomical unit

d) 1000000 Parsec

Explanation

The solar system travels at an average speed of 828,000 km/h. Even at this rapid speed, the solar system would take about 230 million years to travel all the way around the Milky Way.

58. Which of the following statements are not true regarding the Black holes?

a) Black holes are the center of the galaxy.

b) Black holes cannot be viewed directly.

c) Only some of the galaxies are thought to have black hole.

d) The Black holes can change or distract the paths of materials around it.

Explanation

Tucked inside the very center of the galaxy is a monstrous black hole, billions of times as massive as the sun. Although, black holes cannot be directly viewed, scientists can see their gravitational effects as they change and distort the paths of the material around it most galaxies like our milky way, are thought to have a black hole in their heart.

59. Assertion (A): The International Astronomical Union has classified 88 constellations covering the celestial sphere.

Reasoning(R): A Constellation is a recognizable pattern of stars in the night sky from the earth.

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

A constellation is a recognizable pattern of stars in the night sky when viewed from the Earth. International Astronomical Union has classified 88 constellations to cover the entire celestial sphere. Many of the old constellations have Greek or Latin names and are often named after mythological characters.

60. Which is known as the large constellation in the sky?

a) The Ursa Major

b) The Pole Star

c) The Ursa Minor

d) The Milky Way

Explanation

Ursa Major (Saptha Rishi Mandalam) is a large constellation and it covers a large part of the sky. The most striking feature of this constellation is a group of seven bright stars known as big dipper (seven Sages in Indian astronomy).

61. Choose the Incorrect statements.

i) The Ursa Minor lies in the northern sky of the earth.

ii) Little dipper consists of seven stars.

iii) The Pole star lies within the Ursa Major.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Ursa Minor in Latin means ‘the little bear’ it lays in the northern sky. The Pole star – Polaris (Dhrua) lies within this constellation. The main group, ‘little dipper’ consists of seven stars and is quite similar to that found in Ursa Major.

62. What is the reason for different constellations appearing in various times in a year?

a) Revolution of Earth

b) Atmospheric dust

c) Heat energy of the Sun

d) Distance

Explanation

Different constellations become visible in the sky at different times in the year. This happens due to the revolution of the Earth around the Sun.

63. Assertion (A): The stars are bound by gravity that constitutes a system in a galaxy.

Reasoning(R): The Constellation is not real object and it is mere optical appearance.

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

Unlike galaxy, constellations are mere optical appearance and not real objects. In galaxy stars are bound by gravity and constitute a system. In a constellation, one star may be near and another very far, but because they are in the same direction appear to be near to each other in the sky.

64. Which of these prevents the light from the star to travel in a straight line?

a) Atmospheric disturbances

b) The Sun light

c) Planet movements

d) All the above

Explanation

A Star is a luminous heavenly body that radiates energy. With naked eyes, we can see nearly 3000 stars in the night sky and many more with the help of a telescope. The stars are remotely located and appear as tiny dots of light. Their light travels long distances to reach us. The atmosphere disturbances do not allow light to reach us in a straight line path. Because of this the stars appear to twinkle.

65. Which is the nearest star to the Earth?

a) Andromeda

b) Alpha Centauri

c) Milky Way

d) Megallanic Clouds

Explanation

The Sun is the nearest star to the Earth. The next nearest star is Alpha Centauri.

66. How many categories of satellite are classified?

a) 3

b) 4

c) 5

d) 2

Explanation

An object that revolves around a planet in a stable and consistent orbit is called a satellite. Satellites can be classified into two categories –natural and artificial.

67. What is the natural object that revolves around a planet?

a) Moon

b) Asteroids

c) Meteors

d) Stars

Explanation

All natural objects revolving around a planet are natural satellites. They are also called moons. Most moons are spherical, the ones that are not usually asteroids or meteors that were captured by the strong gravity of a planet.

68. Which of this planet has more number of moons?

a) Mars

b) Mercury

c) Venus

d) Jupiter

Explanation

All planets except mercury and Venus in our solar system have moons. Earth has only one moon- whereas planets like Jupiter and Saturn have more than 60 moons.

69. Which was the world’s first artificial satellite?

a) Sputnik-1

b) Aryabhatta

c) Rohini

d) Explorer-1

Explanation

The world’s first artificial satellite launched was Sputnik-1 by Russia,

70. What are the uses of the satellites?

a) Radio transmission

b) Agriculture field

c) Weather forecast

d) All the above

Explanation

Aryabhatta was the first satellite launched by India. These satellites are used in television and radio transmission, studying agriculture yield, locating mineral resources, weather forecasting, locate different places on earth.

71. Which place is the headquarters of the Indian space agency ISRO?

a) New Delhi

b) Bangalore

c) Chennai

d) Mumbai

Explanation

The Indian Space Research Organization (ISRO) is the space agency of the Government of India headquartered in the city of Bangalore. Its vision is to “harness space technology for national development while pursuing space science research and planetary exploration.”

72. Choose the correct statements.

i) Subrahmanyan Chandrasekhar was an Indian -American astrophysicist.

ii) Chandrasekhar was awarded Nobel Prize for physics in the year 1983.

iii) The theoretical models developed by Chandrasekhar were used in later evolutionary stages of stars and black holes.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

Subrahmanyan Chandrasekhar (19October 1910 – 21 August 1995) was an Indian American astrophysicist who spent his professional life in the United States. He was awarded the 1983 Nobel Prize for Physics with William A Fowler. His mathematical treatment of stellar evolution yielded many of the best current theoretical models of the later evolutionary stages of massive stars and black holes. The Chandrasekhar limit is named after him. Chandrasekhar worked on a wide variety of physical problems in his lifetime.

73. In which year the ISRO was formed in India?

a) 1962

b) 1978

c) 1969

d) 1954

Explanation

Formed in 1969, ISRO superseded the erstwhile Indian National Committee for Space Research (INCOSPAR) established in 1962 by the Scientist Vikram Sarabhai. The establishment of ISRO thus institutionalized space activities in India. It is managed by the Department of Space, which reports to the Prime Minister of India.

74. Which country launched the first Indian satellite Aryabhata?

a) The United States of America

b) The Soviet Union

c) China

d) France

Explanation

ISRO built India’s first satellite, Aryabhatta which was launched by the Soviet Union on 19 April 1975. It was named after the Indian astronomer Aryabhata.

75. Which was the first Indian satellite launched by Indian-made launch vehicle SLV-3?

a) Chandrayan-1

b) Galileo

c) Aryabhatta

d) Rohini

Explanation

In 1980, Rohini became the first satellite to be placed in orbit by an Indian-made launch vehicle, SLV-3. ISRO subsequently developed two other rockets: the Polar Satellite Launch Vehicle (PSLV) for launching satellites into polar orbits and the Geosynchronous Satellite Launch Vehicle (GSLV) to place satellites into geostationary orbits.

76. What are GAGAN and IRNSS of ISRO?

a) Launching satellites

b) Navigation systems

c) Satellites

d) Mars mission

Explanation

Satellite navigation systems like GAGAN and IRNSS have been deployed. In January 2014, ISRO used an indigenous cryogenic engine in a GSLV-D5 launch of the GSAT-14.

77. Choose the correct statements.

i) Mars Orbiter Mission was launched on November, 2013 by ISRO.

ii) ISRO was the fourth space agency in the world to reach Mars orbit.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

ISRO sent a lunar orbiter, Chandrayan -1 on 22 October 2008 and a Mars orbiter, Mars Orbiter Mission, on 5 November 2013, which entered Mars orbit on 24 September 2014, making India the first nation to succeed on its first attempt to Mars, and ISRO the fourth space agency in the world as well as the first space agency in Asia to reach Mars orbit.

78. How many satellites were launched by the PSLV-C37 on Feb, 2017?

a) 38

b) 65

c) 104

d) 250

Explanation

On 15 February 2017, ISRO launched 104 satellites in a single rocket (PSLV-C37) and created a world record. ISRO launched its heaviest rocket, Geosynchronous Satellite Launch Vehicle- Mark III (GSLV-Mk III) on 5 June 2017 and placed a communications satellite GSAT-19 in orbit. With this launch, ISRO became capable of launching 4 ton heavy satellites.

79. When Chandrayan 2 was launched by ISRO?

a) July 22, 2019

b) October 22, 2008

c) August 20, 2019

d) December 2, 2018

Explanation

ISRO launched Chandrayan 2 on July 22, 2019, Geosynchronous Satellite Launch Vehicle (GSLV-Mk III). It entered the Moon’s orbit on August 20, 2019 and its lander landed on the Moon on September 7.

80. Which planet space probe was named after Galileo Galilei?

a) Mercury

b) Mars

c) Jupiter

d) Venus

Explanation

In 1989, Galileo Galilei was memorialized with the launch of a Jupiter-bound space probe bearing his name. During its 14-year voyage, the Galileo space probe and its detachable mini-probe, visited Venus the asteroid Gaspra, observed the impact of Comet Shoemaker-Levy 9 on Jupiter, Europa, Callisto, IO, and Amalthea. In order to avoid the possible contamination of one of Jupiter’s moons, the Galileo space probe was purposely crashed into Jupiter at the end of its mission in September 2003.

81. What was the name of the aircraft designed and operated by Dr. A.P.J.Abdul Kalam?

a) Nandhi

b) Agni

c) Red

d) Veena

Explanation

After completing studies at MIT, Abdul Kalam designed an aircraft named ‘Nandhi’ using indigenous materials with the help of indigenous technologists, He operated that flight himself.

82. Which of this launch vehicle was used to launch Rohini-1 satellite?

a) PSLV-2

b) GSLV-1

c) SLV-3

d) GSLV- 4

Explanation

Kalam successfully launched the ‘Rohini-1’ satellite using the India’s first satellite launch vehicle SLV-3 in 1980. He acted as the Project Director when the missiles Thrishul, Agni, Prithvi, Nag and Akash were designed in the Indian Defence.

83. Choose the correct statements.

i) Smiling Buddha was the first nuclear explosion test handled by India in 1974.

ii) Abdul Kalam was the head of the Smiling Buddha project.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

India for the first time experimented nuclear explosion test named ‘Smiling Buddha’ in 1974. Kalam was one among the sixty Aeronautical Engineers in this project.

84. What was the name of the nuclear test project in the year 1999?

a) Operation Sakthi

b) Operation Blue

c) Operation Indira

d) Operation Red

Explanation

Abdul Kalam played a vital role in the nuclear explosion test project in Pokran named “Operation Sakthi” in 1999. The credit that the India has become a nuclear power goes to him.

85. In which year Dr. A.P.J. Abdul Kalam was awarded the prestigious Bharatha Ratna award?

a) 1997

b) 2000

c) 1981

d) 2003

Explanation

The Government of India awarded him the Bharatha Ratna in the year 1997. He was the President of India during the period from 2002-2007.

7th Science Lesson 14 Questions in English

14] Polymer Chemistry

1. Which of these make the fibers?

a) Polymers

b) Proteins

c) Fatty Acids

d) Nucleus

Explanation

Fibers are made up of long chains of natural or synthetic polymers.

2. What is the origin of the word Polymer?

a) Latin

b) French

c) Greek

d) Roman

Explanation

The word ‘Polymer’ is of Greek origin. ‘Poly’ means many and ‘mer’ means basic smaller unit.

3. Define polymerization.

a) Monomers are joined together by covalent bonds to form a polymer.

b) Classification of natural polymers.

c) Recycling process of polymers.

d) Chemical reactions used to form the monomers.

Explanation

Polymers are very long chains made of repeating smaller molecules called ‘monomers’ that are joined together by covalent bonds and the process is called polymerization.

4. Which of these is a common plastic?

a) Polyvinyl Chloride

b) Thermocol

c) Polycarbonate

d) Acrylic

Explanation

Polyvinyl Chloride (PVC) is a common plastic used for water pipes. The monomer and polymers of PVC is shown below.

5. Which of this polymer is mostly used in daily life?

a) Natural polymers

b) Resin

c) Synthetic polymers

d) Monomers

Explanation

Polymers can be classified into natural and synthetic polymers. The most familiar polymers that we use in our daily life are man-made and synthetic.

6. Which of the following is not a natural polymer?

a) Cellulose

b) Carbohydrates

c) Starch

d) Proteins

Explanation

Natural polymers are found in living systems that include proteins and carbohydrates in our bodies and cellulose in wood and paper. They play a very important role in living things to provide structural materials and molecules needed for life processes.

7. Which of these is the basis of protein polymers?

a) Starch

b) Fatty oils

c) Amino acid Monomers

d) Cellulose

Explanation

Protein polymers are made from amino acid monomers (20 different kinds of amino acids). Different combinations of the amino acid monomers create many different protein polymers. Examples of protein polymers include DNA, enzymes, silk, skin, hair, fingernails, feathers and fur.

8. What are the carbohydrate polymers?

a) Lignin

b) Chitin

c) Cellulose

d) All the above

Explanation

Examples of carbohydrate polymers include cellulose, chitin and lignin found in plants. Cellulose is made of sugar molecules and is the main component of cotton used in clothing.

9. Which of this polymer give structure to plants?

a) Chitin

b) Lignin

c) Protein

d) Amino Acid

Explanation

Chitin is found in the cell walls of fungi such as mushrooms and exoskeletons of insects such as crabs and spiders. Lignin consists of a network of polymers and is important in giving structure to plants.

10. Which of this is the byproduct of petrol?

a) Ethylene

b) Plastics

c) Resin

d) Amino acids

Explanation

Synthetic polymers are man-made polymers produced by using raw materials from petroleum oil and gas. Plastics are synthetic polymers. When oils and gases are processed to make petrol, ethylene and propylene monomers are removed as byproducts.

11. What are the building blocks of various polymers?

a) Acetylene

b) Propene

c) Ethylene

d) Methane

Explanation

The Poly Vinyl Chloride (PVC) is made up of many monomers joined together. Ethylene and propylene are the building block monomers that make up many different types of plastics.

12. Which of these factors decide the categories of the polymers?

a) Arrangement

b) Nature of the monomers

c) Characteristics of final polymer

d) All the above

Explanation

Based on the nature of the monomers the way they are arranged in the polymer and the characteristics of final polymer. There are grouped into different categories such as fibres, plastics, proteins.

13. Assertion (A): All the natural and synthetic fibers are called as polymers.

Reasoning(R): Cotton and Wool are the natural fibers used in daily life.

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

We wear clothes, use bags, rope, blankets, etc. in our daily life. They are made of fibres. Once upon a time, people used natural fibres such as cotton and wool. Nowadays, we use a lot of synthetic fibres. All natural and synthetic fibres are polymers.

14. Which is not a natural fiber?

a) Cotton

b) Wool

c) Rubber

d) Silk

Explanation

Fibres are long strands of polymers interwoven to form linear, string-like structures. Fibres that are obtained from plant or animal sources are called natural fibres. Examples include cotton, coconut fibre, hair, wool and silk.

15. Which of the following are synthetic fibers?

a) Polyester

b) Acrylic

c) Nylon

d) All the above

Explanation

Fibres that are made using raw materials from petroleum are synthetic fibres. Examples include polyester, acrylic and nylon.

16. Assertion (A): The natural fibers are used for clothing, insulating materials and containers.

Reasoning(R): All the natural fibers can be knitted, woven and bonded.

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

A large variety of natural fibres are still grown and processed such as cotton, silk, and wool. Natural fibres can be spun into filament, thread or rope. Then they can be woven, knitted, matted or bonded and are used to make clothing, containers, insulation material and many other products we use in our daily life.

17. Choose the correct statements.

i) Synthetic fibers are the byproducts of petro chemical products.

ii) Nylon, Polyester and acrylics are some of the synthetic fibers.

iii) Synthetic fibers are used in tooth brushes, blankets and clothing.

a) i only

b) ii only

c) iii only

d) All the above

Explanation

The discovery of making synthetic fibres out of petrochemicals has replaced the use of many natural fibres. Synthetic fibres such as nylon, polyester and acrylic are used to make many different plastic items you use in your daily life such as clothing, blankets, tooth brushes and stuffing in cushions.

18. What are the types of natural silk?

a) Mulberry silk

b) Muga silk

c) Eri silk

d) All the above

Explanation

Natural silk fibres are obtained from boiling the cocoons of silk worms from specific species of moths. There are four types of natural silk: Mulberry silk, Tasar silk, Muga silk and Eri silk.

19. Which of these silk is mostly produced in India?

a) Mulberry silk

b) Muga silk

c) Eri silk

d) Tasar silk

Explanation

Most of the mulberry silk worldwide is produced in India. Silk is one of the strongest natural fibres and has many uses such as clothing, carpets and parachutes.

20. In which of these places the first rayon factory was established in India?

a) Mumbai

b) Goa

c) Kerala

d) Vishakhapatnam

Explanation

In the 19th century scientists were successful in producing the first artificial silk known as rayon. The first rayon factory in India was established in Kerala in 1946.

21. Assertion (A): Rayon is a complete man-made synthetic fiber.

Reasoning(R): The Natural pulp collected from wood and bamboo are used in rayon making.

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 False but R is True.

d) Both A and R is False.

Explanation

Rayon is a man-made fibre but it is not considered fully synthetic as it is made out of natural cellulose collected from wood pulp. The cellulose that is collected from wood or bamboo pulp is treated with several chemicals.

22. Which of these are not involved in rayon production?

a) Viscose

b) Sodium hydroxide

c) Sodium chloride

d) Carbon disulphide

Explanation

First sodium hydroxide is added to the natural wood pulp followed by carbon disulphide. The cellulose dissolves in the chemicals added to it and produces syrup called Viscose. Viscose is forced through a spinneret (a device made of metal plates with very tiny holes) into a solution of dilute Sulphuric acid. This produces silk-like threads that are cleaned with soap and dried. This new fibre is called rayon.

23. Choose the correct statements.

i) Rayon can be woven like natural silk fibers.

ii) Rayon is mixed with cotton or wool.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

Rayon is cheaper than silk can be woven like natural silk fibre and can be dyed in a wide variety of colors. It can be mixed with cotton to make bed sheets or with wool in the production of carpets and home furnishing products. Rayon is also found in sanitary products, diapers, bandages and gauze for dressing wounds.

24. Assertion (A): Nylon is the first fully processed synthetic fiber.

Reasoning(R): Nylon is the most common synthetic fiber.

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

Nylon is the first fully processed synthetic fibre. It was popular during the Second World War for the use of parachutes and rope materials for climbing. Nowadays, nylon has replaced natural silk in many textiles, and has become one of the most commonly used synthetic fibres.

25. Which of these are the characteristics of nylon?

a) Elastic and light

b) Strong

c) Lustrous

d) All the above

Explanation

Nylon fibre is strong, elastic and light. It is lustrous and easy to wash, which has made it popular for the clothing industry. We use many products made from nylon such as socks, ropes, tents, toothbrushes, car seatbelts, sleeping bags, curtains etc.

26. Which of these is the basic component of nylon?

a) Polyamides

b) Polypropone

c) Acetyl acid

d) Tin

Explanation

Nylon is a plastic polymer made of chemical units called polyamides. Polyamides are made with monomers –hexa methylene di-amine and adipic acid. Solid chips of these polyamides are melted and forced through a heated spinneret which has very, very tiny holes.

27. What are the other names of polyester?

a) Polycot

b) Polywool

c) Terrycot

d) All the above

Explanation

Polyester is another synthetic fibre. It can be drawn into very fine fibres that can be woven like any other yarn. Polyester is sold in the name of polycot, polywool and terrycot etc.

28. Which of these components provide the polycot material?

a) Polyester and cotton

b) Polyester and wool

c) Polythene and cotton

d) Polythene and wool

Explanation

Polycot is a mixture of polyester and cotton; Polywool is a mixture of polyester and wool. PET (Polyethylene Terephthalate) is a very familiar form of polyester. It is used for making water and soda bottles, utensils, films and wires amongst many other useful products.

29. Which of these features of polyester used in cloth making?

a) Wrinkle free

b) Easy to wash

c) Suitable for dress materials

d) All the above

Explanation

Many of the clothes we wear are made out of polyester fibres. Fabrics made from this fibre do not get wrinkled easily and are easy to wash making polyester fabrics suitable for dress materials.

30. Choose the incorrect statements.

i) Acrylic made clothes are less expensive.

ii) Acrylic polymers are available in white color only.

iii) Synthetic fibers are durable and affordable.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

The wool obtained from natural sources is quite expensive whereas clothes made from acrylic are relatively cheap because they are a byproduct of the production of plastics. They are available in a variety of colors. Synthetic fibres are more durable and affordable which has contributed to their widespread use.

31. Which of this fiber can hold their color and brightness for longer time?

a) Wool

b) Cotton

c) Polyester

d) Rayon

Explanation

Synthetic fibres such as polyester and the advantages are that they do not wrinkle easily and they keep their color and brightness for a much longer time than natural fibres such as cotton.

32. What is the main advantage of using the synthetic fibers?

a) Stronger than natural fibers.

b) Easily reusable.

c) Cost of manufacturing is low.

d) Cheaper than natural fibers.

Explanation

A lot of materials such as fishing nets are made from synthetic fibres. One of the main advantages of using synthetic fibres such as nylon is that they are stronger than many natural fibres such as silk or wool. For example a trampoline is made of woven synthetic fibres. These fibres are strong and elastic which gives it the properties to bounce.

33. List out the drawbacks of the synthetic fibers.

a) Absorbs low moisture.

b) Not heat or fire resistant.

c) Does not allow air circulation

d) All the above

Explanation

Drawbacks of Synthetic Fibres: This is because one disadvantage of synthetic fibres such as polyester is that they are not heat resistant and catch fire easily. In summer it is better to wear clothing that is made out of cotton materials rather than synthetic. This is because most synthetic fibres absorb very little moisture and do not allow air circulation making them hot and uncomfortable to wear. The disadvantage is that they break down into very small pieces called micro-plastics which cause pollution to soil and water bodies such as rivers, lakes and oceans.

34. In which of the fields plastics are used to make advancements?

a) Food safety

b) Healthcare

c) Transport

d) All the above

Explanation

Plastics have helped us to make advancements in technology, building, healthcare, transport and food safety. Plastics have completely occupied our life because of their characteristic qualities.

35. What are the features of plastics?

a) Lightweight

b) Complex shapes

c) Waterproof

d) All the above

Explanation

Plastics have many positive qualities such as lightweight, strong and they can be molded into complex shapes. They are also flexible and waterproof and some plastics are even UV resistant. Plastics are also cheap and convenient for us to use.

36. Who was the creator of the first plastic Parkesine?

a) Edmund Alexander Parkes

b) Alexander Fleming

c) Lavoisier

d) Robert Boyle

Explanation

Plastic has been around for less than 200 years. Edmund Alexander Parkes was the creator of the first plastic called ‘Parkesine’.

37. Assertion (A): All the plastics have the same type of arrangement of units.

Reasoning(R): The monomers are arranged in linear manner for all types of plastics.

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 plastics we use in our daily life are also made up of polymers. All plastics do not have the same type of arrangement of units. In some articles, the arrangement of a monomer is linear, and in some other items, the arrangement of articles is cross-linked.

38. How many types of plastics are categorized based on the arrangement of monomers?

a) 4

b) 2

c) 3

d) 5

Explanation

Depending on the type of arrangement, we have two main types of polymers – thermoplastics and thermoset.

39. Which is an example of thermoplastics material?

a) Polyethylene

b) Acrylic

c) Thermocol

d) Bio-plastics

Explanation

Thermoplastics: Polyethylene (also called polythene) is an example of a plastic. It is used for making polythene carry bags which are commonly used. When you burn a polythene carry bag, it melts and turns into liquid along with the production of an offensive odor a bright flame and soot.

40. Assertion (A): Polyethylene terephthalate is an example for thermoplastics.

Reasoning(R): Thermoplastics can be modified and turned into another plastic item.

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

Another example is a PET (Polyethylene Terephthalate) bottle, when we fill it with boiling water, it gets deformed. Plastics which can be easily softened and bent when heated are known as thermoplastics. These plastics can be modified and turned into another plastic item through the process of recycling.

41. Which of these are the properties of thermoset plastics?

a) Remains hard when heated.

b) Easily molded when heated.

c) Tangled polymer chains.

d) Weak attraction force.

Explanation

Thermoset: On the other hand, there are some plastics, which once they are molded cannot be softened through heating them. These are called thermosetting plastics.

42. Which of these are used to make electrical switches?

a) Bakelite

b) Aluminium

c) Nylon

d) Thermocol

Explanation

Bakelite and melamine are some examples of thermosetting plastics. Bakelite is a poor conductor of heat and electricity. It is used for making electrical switches and handles of various utensils.

43. What is the usage of melamine?

a) Pipes

b) Fire and heat resistant tiles and fabrics

c) Bullet proof materials

d) Toys

Explanation

Melamine resists fire and can tolerate heat. It is used for making floor tiles and fabrics that resist fire.

44. What are the properties of thermoplastic?

a) Weak force of attraction

b) Tangled polymer chain

c) Soften when heated

d) All the above

Explanation

45. What are the uses of the resin codes?

a) Categorizing types of plastics

b) For recycling purpose

c) Identify various plastics

d) All the above

Explanation

The resin codes are a universal way of categorizing different types of plastic, which helps us separate plastics so that it is easier to recycle them.

46. Which of these harmful materials are present in the polyvinyl chloride?

a) Cadmium

b) Lead

c) Tin

d) Both a and b

Explanation

Polyvinyl Chloride- PVC resin code#3 has heavy metals such as cadmium and lead which are toxic chemical which are harmful to your health.

47. Which of these plastic is designed to for single purpose usage?

a) PETE

b) PEHD

c) HIPS

d) LLDPE

Explanation

PLASTIC RESIN CODE CHART

48. Which of these products are made by PEHD material?

a) Bullet proof materials

b) Ropes

c) Rice and cement sacks

d) All the above

Explanation

49. Which of the following material has good resistance to fire and weathering?

a) PELD

b) Vinyl

c) Thermocol

d) Polycarbonate

Explanation

50. Which of these plastic is flexible but strong material?

a) Vinyl

b) PELD

c) XPS

d) Nylon

Explanation

51. Identify the incorrect Match.

A. Nylon i) Clothes

B. Acrylic ii) Helmets

C. Polycarbonate iii) Food containers

D. Polyurethane iv) Foam

a) i only

b) ii only

c) iii only

d) iv only

Explanation

52. Which of the Resin code plastics are considered as the toxic plastics?

a) 05

b) 02

c) 04

d) 06

Explanation

53. Which of these are not related to the plastics with no code?

a) It can be any plastic item.

b) The manufacturer did not follow the rules for this type.

c) It could be harmful.

d) It can be used with limitation.

Explanation

54. Which of these house hold products contain the micro beads that cause pollution?

a) Tooth paste

b) Face wash

c) Body scrubs

d) All the above

Explanation

Some micro plastics are also found in household products. Examples are micro beads that can be found in toothpaste, face wash and body scrubs. Micro beads are washed down in drains and end up in the soil , rivers, lakes and the ocean Micro beads are washed down in drains and end up in the soil, rivers, lakes which cause pollution.

55. When did the Government of Tamilnadu ban the usage of one-time plastics?

a) 2019

b) 2017

c) 2009

d) 2016

Explanation

The Government of Tamil Nadu has banned one-time use and throws away plastics such as plastic carry bags, plates, straws and water pouches. This is an indication that important efforts are taking place to reduce negative consequences of plastics on the environment.

56. Which of these are the dangerous pollutions in the Ocean?

a) Poly peptide pollutants

b) Poly methylene

c) Persistent Organic pollutants

d) Poly propane products

Explanation

Dangerous pollution called Persistent Organic Pollutants (POPs) floating in the ocean sticks to these small pieces of plastic making them toxic. Marine animals such as shrimp and fish often eat micro plastics, confusing them for their natural source of food. The toxins build up in these animals and move up the food chain and can end up in our bodies. Micro plastics can be found in the food we eat, the water we drink, and the air we breathe.

57. Which of the plant starch are substitute for some plastics?

a) Poly Lactic Acid

b) Cellulose

c) Starch

d) None of the above

Explanation

Poly Lactic Acid (PLA) a substitute for some types of plastics. Poly Lactic Acid or poly lactide is compostable and bioactive thermoplastic. This polymer is obtained from plant starch such as corn, sugarcane and pulp from sugar beets. PLA is a biodegradable material. It is useful for making food packaging, garbage bags and disposable table ware.

58. What are the disposal methods for the plastic products?

a) Recycle

b) Incinerate

c) Landfill

d) All the above

Explanation

Plastic waste ends up being recycled, incinerated, landfilled, dumped or ends up littering our environment.

59. Which of the disposal method is least followed globally in plastic disposals?

a) Landfills

b) Incineration

c) Recycle

d) Littering

Explanation

It is estimated that from all the plastic waste ever produced, 79% is in landfills, dumps or in the environment 12% has been incinerated and only a small 9% is recycled.

60. What is the 5R principle used for plastic disposal?

a) Reuse, Replace, Rebuild, Recycle and Recover.

b) Reduce, Replace, Reproduce, Reimburse, Recover.

c) Refuse, Reduce, Reuse, Recycle, Recover.

d) Recommend, Resend, Reuse, Recollect, Recover.

Explanation

One way to look at plastic disposal is the 5R Principle – Refuse, Reduce, Reuse, Recycle and Recover. We have already learned about the waste pyramid and how the different methods of waste disposal can be seen in terms of the best option to the least favorable in this order: Refuse (Avoid), Reduce, Reuse, Recycle, Recover (Compost and Incinerate) and Landfill.

61. Define Down-cycling of plastics.

a) Every time plastic is melted and recycled loses its quality.

b) Recycling the used plastics with new technologies.

c) Landfilling the used plastics.

d) Degradation of plastics.

Explanation

Recycling of plastics is challenging and it is important to know that plastics cannot be recycled forever. There are so many different types of plastics, which are often mixed together making it difficult to separate them back into the original material. Every time plastic is melted and recycled it loses quality this is called ‘Down-cycling’. Recycling of plastic waste cannot be the only solution to plastic pollution.

62. Which of these energy sources are derived from the solid wastes?

a) Thermal energy

b) Wind energy

c) Solar energy

d) Hydro power

Explanation

Solid waste can be converted into resources such as electricity and compost through thermal and biological means. Burning plastics in a large furnace or in the open is bad for the environment.

63. Choose the correct statements.

i) Toxic pollutants are released by open burning of plastics.

ii) Incinerator burning of plastics is used to produce energy.

a) i only

b) ii only

c) Both i and ii

d) Neither i nor ii

Explanation

Open burning of plastics releases toxic pollutants into the air and soil, which are harmful to our health animals and the environment. Burning plastics at high temperatures in incinerators and trapping the gases and collecting the toxic ash are widely used to produce energy. This is often seen as a positive way to deal with plastic waste.

64. Assertion (A): Plastics in landfills is the most common way for disposing the plastics.

Reasoning(R): Landfills of plastics can lead to air, soil and ground water pollution.

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

Plastic waste often ends up in landfills that are huge holes where waste is buried to keep it separate from the environment. This is the most common way for plastics to be disposed of around the world. Plastics make up 7-13% of waste that is sent to landfills on a global scale. Plastics in landfills can still lead to pollution of the air, soil and groundwater. Over time landfills can degrade, and the toxic chemicals in certain plastics can leak out into the environment.

65. On what basis plastics are classified into degradable and compostable plastics?

a) Nature of degradation

b) Sources

c) Chemical process

d) Physical Characteristics

Explanation

The concept of biodegradable plastics or bio-plastics was first introduced in the 1980s. Based on the nature of degradation, there are two main types of plastics: degradable plastic and compostable plastic.

66. Choose the Incorrect statements regarding the degradable plastics.

i) Degradable plastics are made from petroleum oil.

ii) Chemical additives are added for faster breakdown than conventional plastics.

iii) Degradable plastics are broke down when exposed to oxygen, water and sunlight.

a) i only

b) ii only

c) iii only

d) None of the above

Explanation

Degradable plastics are made from petroleum oil or gas which is the same as conventional plastics. The difference is that they have a chemical or additive added to them to make them breakdown faster than conventional plastics when they are exposed to sunlight, oxygen or water.

67. Assertion (A): Degradable plastics are broken down into micro-plastics.

Reasoning(R): The degradable plastics do not break down completely in the environment.

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

Degradable plastics breakdown into tiny pieces called micro-plastics and these stay in our environment for a very long time. It is very important to understand that degradable plastics do not breakdown completely in the environment. Scientists have found that micro-plastics in the ocean are really bad and it is likely that these tiny pieces in the soil are also harmful.

68. What are the known sources of the compostable plastics?

a) Sugar cane

b) Shrimp shells

c) Avocado seeds

d) All the above

Explanation

Compostable plastics are derived from renewable resources such as corn, sugar cane, avocado seeds or shrimp shells.

69. Assertion (A): Compostable plastics are completely broken down by microbes.

Reasoning (R): The broken compostable plastics are turned into carbon-di-oxide, methane and water.

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

Compostable plastics can be broken down completely by microbes and turned back into food for plants carbon dioxide, methane, water and other natural compounds.

70. Which of these plastics could be digested by the Ideonellasakaiens bacteria?

a) Polyester

b) Polycarbonate

c) Polyethylene Terephthalate

d) Polyurethane

Explanation

In 2016, scientists from Japan tested different bacteria from a bottle recycling plant and found that Ideonellasakaiens is 201-F6 could digest the plastic used to make single-use drinks bottles that are made of polyethylene terephthalate (PET).

71. Name the enzyme that breaks down plastic into smaller molecules?

a) PETase

b) Petx

c) PITE

d) Ps

Explanation

The Ideonellasakaiens bacteria works by secreting an enzyme known as ‘PETase’, that breaks down plastic into smaller molecules. These smaller molecules are then absorbed by the bacteria as a food source.

72. Assertion (A): Glass is the most oldest and versatile man-made material.

Reasoning(R): Glass retains its quality even after recycling many times.

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

Glass is one of the world’s oldest and most versatile human created materials. Glass is the only material that can be recycled over and over again without losing its quality.

73. Which of the following is not true regarding the qualities of glass?

a) Made from opaque sand.

b) It is partially transparent.

c) Similar to solid material.

d) It is also available in liquid form.

Explanation

Glass is bit of a riddle. It is hard enough to protect as but it shatters with incredible ease. It is made from opaque sand, yet, it is completely transparent. Most surprisingly, it behaves like a solid material, but it is also a sort of weird liquid in disguise.

74. Which of these is added with the silicon-di-oxide prior to the cooling process?

a) Lead

b) Chromium

c) Sodium Carbonate

d) Iron oxide

Explanation

Glass is prepared by heating (SiO2) silicon-di-oxide until it melts, say to about 1700◦C and Sodium Carbonate is added to it. Then it is cooled down really fast. When SiO2 silicon-di-oxide melts, the silicon and oxygen atoms break out of their crystal structure. If we cooled it slowly, the atoms would slowly line up back into their crystalline arrangement.

75. In which of the stage glass is considered as polymers?

a) Cooling stage

b) High temperature region

c) Molten state

d) None of the above

Explanation

Materials like glass are called as amorphous. At the cooling stage glass is linear in arrangement inorganic in nature and has a structure very similar to glass and they are considered as polymers.

76. Which of these are used in a commercial glass plant?

a) Soda ash

b) Limestone

c) Used glass

d) All the above

Explanation

In a commercial glass plant, sand is mixed with waste glass (obtained from recycling collections), soda ash (sodium carbonate) and limestone (calcium carbonate) and heated in a furnace.

77. What is the purpose of adding soda ash in the making of commercial glass?

a) Increase the melting capacity

b) Dissolving capacity

c) Reduce the melting point of sand

d) Reduce the temperature

Explanation

The soda ash reduces the sand’s melting point and produces a kind of glass that would dissolve in water. The limestone is added to stop that happening. The end product is called soda-lime-silica glass. It is the ordinary glass we see all around us.

78. Which of this component is used to make green-tinted glass?

a) Iron

b) Lead

c) Chromium

d) Both a and c

Explanation

Other chemicals are added to change the appearance or properties of the finished glass. For example, iron and chromium based chemicals are added to the molten sand to make green-tinted glass.

79. What is the main component of the oven-proof glass?

a) Boron oxide

b) Phosphorous

c) Silica gel

d) Ferrous oxide

Explanation

Oven-proof borosilicate glass (widely sold under the trademark PYREX) is made by adding boron oxide to the molten mixture. Adding lead oxide makes from a sandwich or laminate of multiple layers of glass and plastic bonded together.

80. Which of this glass type is used in vehicle wind shields?

a) Toughened glass

b) Opaque glass

c) Thin glass

d) All the above

Explanation

Toughened glass used in car wind shields is made by cooling molten glass very quickly to make it much harder.

7th Science Lesson 15 Questions in English

15] Chemistry in Daily Life

1. Which among the following is a special combination of dry salts that is mixed with safe water?

1. ORS
2. Antacid
3. Penicillin
4. All the above

Explanation

ORS (Oral Rehydration Solution) is a special combination of dry salts that is mixed with safe water. It can help to replace the fluids lost due to diarrhoea.

2. During which war in 1917 Therapy with Oral Rehydration Solution (ORS) reduced cholera death rates from 50% to 3% among thousands of refugees?

1. Bangladesh liberation war
2. Assam liberation war
3. Nepal liberation war
4. Myanmar liberation war

Explanation

During the Bangladesh liberation war, Therapy with Oral Rehydration Solution (ORS) in 1971 reduced cholera death rates from 50% to 3% among thousands of refugees.

3. Which among the following Indian doctor had to manage the shortage of saline bottles and coup up with the dehydration faced by the refuges during Bangladesh liberation war?

1. Swaran Singh
2. John Clemens
3. Dilip Mahalanabis
4. R. N. Kao

Explanation

An Indian doctor, Dilip Mahalanabis, had to manage the shortage of saline bottles and coup up with the dehydration faced by the refuges. Dr Dilip Mahalanabis showed the efficacy of ORS in cholera cases among Bangladeshi refugees (1971-72). Further field trial during the cholera epidemic in Manipur attested to its efficacy, ORS has since saved the lives of millions of children around the world.

4. In which among the following state during field trial during the cholera epidemic attested to its efficacy, ORS has since saved the lives of millions of children around the world?

1. Kerala
2. Manipur
3. Nagaland
4. Rajasthan

Explanation

The field trial during the cholera epidemic in Manipur attested to its efficacy, ORS has since saved the lives of millions of children around the world.

5. Which among the following statement is correct

1. In the normal healthy intestine, there is a continuous exchange of water through the intestinal wall. Up to 40 litres of water is secreted and very nearly as much is reabsorbed every 24 hours. This mechanism allows the absorption of soluble metabolites into the bloodstream from digested food.
2. However, when a person becomes sick, due to diarrhoea, water is expelled and the body is not able to retain the liquid balance. This is called as ‘dehydration’. It is not the diarrhoea that kills, but the dehydration’ resulting from the infection that kills. If more than 10% of the body’s fluid is lost death occurs.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

Explanation

In the normal healthy intestine, there is a continuous exchange of water through the intestinal wall. Up to 20 litres of water is secreted and very nearly as much is reabsorbed every 24 hours. This mechanism allows the absorption of soluble metabolites into the bloodstream from digested food.

6. In addition to water loss which among the following are lost during diarrhoea?

1. Sodium and calcium
2. Sodium and hydrogen
3. Sodium and potassium
4. Calcium and hydrogen

Explanation

In a state of diarrheal disease there is imbalance and much more water is secreted than reabsorbed causing a net loss to the body which can be as high as several litres a day. In addition to water loss, sodium and potassium are also lost.

7. Dr Dilip Mahalanabis found by adding which to the salt solution, it can be absorbed by body?

1. Calcium
2. Sulphide
3. Nitrogen
4. Glucose

Explanation

The saline bottle directly transfers water and sodium into the blood stream. However, for the saline water is administered through mouth, intestinal wall, is a not able to absorb neither water nor sodium. Dr Dilip Mahalanabis found that if glucose (sugar) is added to the salt solution, then all the three- water, sodium and glucose are absorbed by the body.

8. Only with adequate sodium concentration in the intestinal wall, water can be absorbed by it through a process known ______

1. Conversion
2. Osmosis
3. Reduction
4. All the above

Explanation

Certain concentration of sodium (Na) is needed for proper functioning of the body For, example, only with adequate sodium concentration in the intestinal wall, water can be absorbed by it through a process known as osmosis. If there is inadequate salt in the intestinal wall the body will not be able to absorb water. Through the process of osmosis, the salts and sugars pull water into your bloodstream and speed up rehydration.

9. How many level teaspoons of sugar is needed to make homely made of ORS?

1. Two
2. Three
3. Four
4. Six

Explanation

Let us see homely made of ORS, be very careful to mix 6 level teaspoons of sugar and 1/2 level teaspoon of salt dissolved in 1 litre of clean water. Too much sugar can make diarrhea worse. Too much salt can be extremely harmful to the child. Making the mixture a little too diluted (with more than 1 litre of clean water) is not harmful.

10. Which is a set of symptoms caused by excess production of acid by the gastric glands of the stomach?

1. Ulcer
2. Diarrhoea
3. Constipation
4. Acidity

Explanation

Acidity is a set of symptoms caused by excess production of acid by the gastric glands of the stomach.

11. Which among the following is produced in stomach to help digest and break down food?

1. Hydrochloric acid
2. Sulphuric acid
3. Nitric acid
4. Perchloric acid

Explanation

Your stomach naturally produces gastric or hydrochloric acid (HCl) to help digest and break down food. Acidity issues arise when there is excess production of this acid due to triggers such as acidic foods, spicy food, alcohol, dehydration and stress. When acidity occurs, the excess acid may move up from your stomach to your oesophagus.

12. What is the PH of lining of the stomach which is designed as such to withstand a high acidic environment?

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

Explanation

The lining of your stomach with a pH of 1 to 3 is designed as such to withstand a high acidic environment.

13. When we have acidity or heartburn, we are administered a class of medicines known as ________

1. Paracetamol
2. Calpol
3. Dolo
4. Antacid

Explanation

When we have acidity or heartburn, we are administered a class of medicines known as antacids. They are actually weak bases. As learned in chemistry, when a base is mixed with an acid a neutralization reaction occurs. When antacids are consumed, it creates a chemical reaction in the stomach lowering the acidity and makes the digestive acids less corrosive and damaging.

14. Which among the following is not the antacids?

1. Calcium Carbonate
2. Aluminium Hydroxide
3. Formic Hydroxide
4. Magnesium Carbonate

Explanation

Most of the common antacids are Sodium Bicarbonate (NaHCO₃), Calcium Carbonate (CaCO₃), Magnesium Hydroxide (Mg (OH)₂), Magnesium Carbonate (MgCO₃) and Aluminium Hydroxide

Al (OH)₃. The chemical reaction created when Magnesium Hydroxide neutralizes HCI in the stomach and intestine

15. Who among the following discovered antibiotics in 1928?

1. Louis Plaster
2. Robert Koch
3. Alexander Fleming
4. Howard Florey

Explanation

The discovery of antibiotics was an accident, which happened in 1928 while a British bacteriologist, Dr Alexander Fleming.

16. On researching which among the following bacteria Dr Alexander Fleming discovered Fleming?

1. Staphylococcus
2. Anthracis
3. Chlamydia Tetani
4. Pasteurella

Explanation

Dr Alexander Fleming was involved in research on staphylococcus bacteria, he developed antibiotics. This bacterium was meant to cause deadly diseases such as pneumonia, sour throat, etc.

17. Which among the following statement was correct

1. The discovery of antibiotics happened while Alexander Fleming was culturing the bacteria on a nutrient agar media in a Petri dish. He went on a holiday carelessly leaving the dish in his laboratory table without cleaning and sterilization. After several days, when he returned back, he observed the growth of mould (kind of common fungus, which grows on stale bread/ cheese) on a part of the Petri dish.
2. He also observed that there was no bacterial growth surrounding the mould, which indicated that something in the mould had prevented the growth of bacteria in the culture medium. On further research, Fleming identified that the “mould juice” was capable of killing a wide variety of harmful bacteria.
3. Ages ago, there was a time where even a small infected wound can cause death in human beings. The discovery of antibiotics changed all. Now armed with antibiotics, many deadly infectious diseases can be tackled, which once meant to cause serious illness and death.
4. Both 1 and 2
5. Both 1 and 3
6. Both 2 and 3
7. All 1, 2 and 3

18. Fleming identified that the “mould juice” was capable of killing which among the following harmful bacteria?

1. Streptococcus
2. Meningococcus
3. Diphtheria Bacillus
4. All the above

Explanation

Fleming identified that the “mould juice” was capable of killing a wide variety of harmful bacteria, such as streptococcus, meningococcus and diphtheria bacillus.

19. Which was the world first antibiotics discovered by Alexander Fleming?

1. Paracetamol
2. Penicillin
3. Aspirin
4. Codeine

Explanation

The world first antibiotics is penicillin discovered by Alexander Fleming.

20. Who among the following used had used mouldy bread to treat infected wounds thousands of years ago?

1. Egyptians
2. Greeks
3. Serbians
4. All the above

Explanation

Fleming was not the first using moulds and other living micro-organisms to treat infections. Thousands of years ago, the ancient Egyptians, had used mouldy bread to treat infected wounds. Similar practices were observed among ancient Greeks, Serbians and even among Indians. While these were perhaps partially effective, their efficacy is nowhere near the modern antibiotics.

21. What was the name given to the mould by Fleming?

1. Penicillium tularensis
2. Penicillium typhi
3. Penicillium rattus
4. Penicillium notatum

Explanation

Fleming named the mould penicillium notatum, from which the antibiotic penicillin was isolated.

22. Which among the following is not the antibiotics isolated from the plants/micro-organisms and used as medicines against infectious diseases?

1. Chloramphenicols
2. Chlorpheniramine
3. Tetracyclines
4. Cephalosporin

Explanation

Naturally, many micro-organisms and plants synthesize chemicals which are toxic in nature to protect them from invading organisms. The biosynthesized chemicals isolated from the plants/micro-organisms and used as medicines against infectious diseases. These substances were called as antibiotics. Ex: Chloramphenicols, tetracyclines, Penicillin derivatives, cephalosporin’s and their derivatives. Today, many infectious diseases in the world are rare due to the advancement in research.

23. Which among the following statement is correct

1. Antibiotics work effectively for viruses like cold and the flu. The over use of antibiotics makes it inactive or less effective. Antibiotic resistance is defined as the ability of the microorganisms to resist the effects of an antibiotic to which they were once sensitive.
2. Thus, the antibiotics become less effective and we are forced to either consume a larger dose or shifting towards the use of other virulent variants of antibiotics. Thus, the research on antibiotics is of great importance to combat the virulent and mutated microorganisms.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

Explanation

Antibiotics don’t work for viruses like cold and the flu. The over use of antibiotics makes it inactive or less effective. Antibiotic resistance is defi ned as the ability of the microorganisms to resist the effects of an antibiotic to which they were once sensitive.

24. Which among the following statement is correct

1. Injury, burn, pressure from sharp objects and other conditions cause pain in our body. The unpleasant feeling may be a burning sensation in the tissue around the injury, throbbing headache or ache of arthritis. Back pain, neck pain, joint pain, headaches, pain from nerve damage, pain from an injury and pain related to diseases are some of the most common pains.
2. The unpleasant emotion of ‘pain’ is created in the brain and not at the spot of the injury. If the pain is severe, say from burn, the impulse sent to brain trigger immediate response. Reacting to the signal from the brain, muscle pull our hand from the fire. Reacting to the message received from the pain spot, the brain sends back messages that initiate healing process.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

25. Which among the following was released by brain addition to release of pain suppressing chemicals by triggering?

1. Platelets
2. Melanin
3. Keratin
4. All the above

Explanation

Brain can trigger to release pain suppressing chemical and additional flow of additional white blood cells and platelets to help repair tissue at an injury site.

26. Which are the pain suppressing chemicals released by the body?

1. Analgesics
2. Antipyretic
3. Histamines
4. All the above

Explanation

Analgesics or pain killers are the pain suppressing chemicals released by the body. They suppress the feeling of ‘pain’. These analgesics drug selectively relieves pain by acting either in CNS (Central Nerves System) or on peripheral pain mechanism, without significantly altering consciousness.

27. Paracetamol interact with the receptors and reduce the intensity of pain signals to the brain, also suppresses the release of substances, called ________

1. Dopamine
2. Prostaglandins
3. Serotonin
4. Endorphins

Explanation

When we are affected by fever, often we are administered Paracetamol. Paracetamol interact with the receptors and reduce the intensity of pain signals to the brain, also suppresses the release of substances, called prostaglandins that increase pain and body temperature.

28. Which was the first local anaesthetic?

1. Cocaine
2. Procaine
3. Tolycaine
4. Articaine

Explanation

The first local anaesthetic was cocaine was isolated from coca leaves.

29. Who isolated cocaine from coco leaves in 1860?

1. Franz Betz
2. Albert Nieminen
3. Heinrich Vogl
4. Max Alvary

Explanation

Th e first local anaesthetic was cocaine was isolated from coca leaves by Albert Nieminen Germany, 1860.

30. Traditional anti-inflammatory agents can be classified into how many types?

1. Two
2. Three
3. Four
4. Six

Explanation

Traditional anti-inflammatory agents are classified into two types. i) Non – narcotic and ii) Narcotic drugs.

31. Which among the following is not the narcotics grugs?

1. Codeine
2. Aspirin
3. Opium
4. Morphine

Explanation

Non – narcotic (Non – additive) analgesics E.g., Aspirin.

32. Which among the following is not the Non-narcotic?

1. Aspirin
2. Ibuprofen
3. Diclofenac
4. Carfentanil

Explanation

Carfentanil is a narcotic drug.

33. What is the range of our body temperature in normal course?

1. 98.4 to 98.6 degrees Fahrenheit
2. 101.2 to 102.8 degrees Fahrenheit
3. 104.4 to 104.8 degrees Fahrenheit
4. 88.4 to 89.2 degrees Fahrenheit

Explanation

In normal course our body temperature is ranges from 98.4 to 98.6 degrees Fahrenheit. When the temperature goes above this level it is called fever. Most common cause of fever is infection. Bacteria and virus cannot thrive above a certain temperature. To defend the invading virus and bacteria the immunity system increases the body temperature.

34. Once infection is sensed; the immune system releases a chemical called _____

1. Cortisol
2. Progesterone
3. Pyrogen
4. Estrogen

Explanation

Once infection is sensed, the immune system releases a chemical called pyrogen. These pyrogens released into bloodstream reaches the hypothalamus, present at the basal part of the brain. The function of Hypothalamus is to control the body temperature.

35. Sensing the pyrogens, hypothalamus increases the body temperature by releasing a chemical called __________

1. Dopamine
2. Oxytocin
3. Glutamate
4. Prostaglandin

Explanation

Sensing the pyrogens, hypothalamus increases the body temperature by releasing a chemical called prostaglandin.

36. Which among the following is the maximum internal body temperature above which, this may cause damage to our body protein and the brain may experience seizures and delirium?

1. 98⁰ F
2. 101⁰ F
3. 103⁰ F
4. 105⁰ F

Explanation

Normally little fever is good as it helps to arrest the growth of infection. However, if the internal body temperature exceeds 105°F, this may cause damage to our body protein and the brain may experience seizures and delirium. The prolonged high fever may also cause death.

37. Which are chemical substances that reduce fever that suppress the release of prostaglandin and reduce fever?

1. Antihistamine
2. Antiseptic
3. Antipyretic
4. All the above

Explanation

Antipyretics (anti – against and pyretic -Feverish) are chemical substances that reduce fever. They suppress the release of prostaglandin and reduce fever.

38. Which among the following is not the Antipyretic?

1. Diphenhydramine
2. Paracetamol
3. Ibuprofen
4. Aspirin

Explanation

The most common and well known anti pyretic is paracetamol. Other antipyretics and anti-inflammatory agents include Aspirin, Ibuprofen, Diclofenac.

39. Which are substances applied to the exterior of a body that kill or inhibit microbes and infective agents?

1. Antihistamine
2. Antiseptic
3. Antipyretic
4. All the above

Explanation

Antiseptics are substances applied to the exterior of a body that kill or inhibit microbes and infective agents. Antiseptics can be effective against one or a combination of bacteria, fungi, viruses or other microorganisms.

40. Which among the following is the natural anti septic?

1. Garlic
2. Turmeric
3. Aloevera
4. All the above

Explanation

Natural antiseptics are 1. Garlic, 2. Turmeric 3. Aloevera. All antiseptic are disinfectants but not all disinfectants are not antiseptic. Antiseptic can be applied on the live tissues, where disinfectants can be applied on in animate object.

41. Which among the following is not in the mixture of Dettol?

1. Chloroxylenol
2. Terpincol
3. Boric acid
4. None of the above

Explanation

Dettol is Mixture of chloroxylenol and terpincol.

42. Which among the following is not the ingredient of Tincher?

1. Iodoform
2. Boric acid
3. Ethanol
4. None of the above

Explanation

Tincher ingredients are Iodine + 2 to 3% alcohol – Water mixture Soap, Iodoform, phenolic solutions, ethanol, Boric acid, are examples.

43. Which among the following statement is correct

1. Anti-histamines are defined as drugs that combat the histamine in the body that are used for treating allergic reactions and cold symptoms. Histamine is a chemical messenger involved in number of complex biological reactions.
2. When a foreign body such as pollens enters the body, the immune system believes those substances to be harmful and generates the release of histamine. When histamine is released, it will interact with the histamine receptors on the cell surface or within a target cell and cause changes in the bodily functions.
3. This stimulates many hard muscles to expand, such as Soleus and Gastrocnemius. In certain hard muscles, they cause relaxation of blood capillaries which normalise the flow of lymph and its protein content and lead to the formation of edema (redness and rashes).
4. Both 1 and 2
5. Both 1 and 3
6. Both 2 and 3
7. All 1, 2 and 3

Explanation

This stimulates many smooth muscles to contract, such as gastrointestinal tract and bronchi. In certain smooth muscles, they cause relaxation of blood capillaries which increase the flow of lymph and its protein content and lead to the formation of edema (redness and rashes).

44. Which among the following is not the Antihistamine?

1. Diphenhydramine
2. Chlorpheniramine
3. Cimetidine
4. Tetracyclines

Explanation

Antihistamines or histamine receptor antagonists oppose selectively all the pharmacological effects of histamines. For, Ex. Diphenhydramine, chlorpheniramine, cimetidine. The adverse effects of antihistamines are mouth dryness and sleepiness.

45. How many ways are there to the intake of medicine?

1. Two
2. Three
3. Four
4. Six

Explanation

The science or practice of the diagnosis, treatment, and prevention of disease. There are many ways to intake the medicine. 1. Oral use 2. External use 3. Injections (Intra muscular/Intra venous).

46. Which is a chemical reaction that occurs in the presence of a fuel and an oxidizing agent that produces energy, usually in the form of heat and light?

1. Reduction
2. Ionisation
3. Combustion
4. All the above

Explanation

Can you guess what is common in rusting or iron, burning coal and the flame of candle? They all undergo a chemical reaction known as combustion. Combustion is a chemical reaction that occurs in the presence of a fuel and an oxidizing agent that produces energy, usually in the form of heat and light.

47. Any reaction that involves reaction with oxygen is called ____

1. Oxymoron
2. oxidation
3. oxical
4. All the above

Explanation

What we call as ‘burning’ is really a combustion reaction. In fact, combustion is one of the first chemical reactions intentionally harnessed by humans. Any reaction that involves reaction with oxygen is called oxidation reaction.

48. Which among the following is the correct equation for combustion of hydrocarbon with oxygen, typically carbon dioxide and water are produced?

1. CH₄+2O₂ → CO₂+2H₂O+Heat energy
2. CH₃+O₂ → CO+H₃O+Heat energy
3. CH₄+O₂ → CO+H₄O+Heat energy
4. CH₃+2O₂ → CO₃+2HO+Heat energy

Explanation

In the combustion of hydrocarbon with oxygen, typically carbon dioxide and water are produced. CH₄+2O₂ → CO₂+2H₂O+Heat energy.

49. When a combustion reaction releases heat, the reactions are called _____

1. Exothermic
2. Endothermic
3. Both exothermic and endothermic
4. None of the above

Explanation

All combustion reactions are exothermic; that is they release heat.

50. The minimum temperature at which a substance catches fire and burns is called ____

1. Flash point
2. Ignition temperature
3. Combustion temperature
4. Closure temperature

Explanation

The minimum temperature at which a substance catches fire and burns is called its ignition temperature. A substance will not catch fire and burn if its temperature is lower than its ignition temperature. Different substances have different ignition temperatures.

51. Substances which have very low ignition temperature and can easily catch fire with a flame are called ______

1. Combustible substance
2. Inflammable substance
3. Projectile substance
4. Volatile substance

Explanation

Substances which have very low ignition temperature and can easily catch fire with a flame are called inflammable substances. E g. Petrol. Alcohol, LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas), etc.

52. Which is a zone of combustions of a combustible substance which vaporize during burning?

1. Light
2. Flame
3. Oxygen
4. Heat

Explanation

Flame is a zone of combustions of a combustible substance. Substances which vaporize during burning produce flames.

53. Which mong the following statement is incorrect

1. Flame is actually a chemical reaction. To be specific, the flame is a mixture of gases (vaporized fuel, oxygen, carbon dioxide, carbon monoxide, water vapor, and many volatile materials) and so is matter. The light and heat produced by the flame is matter, not energy. But fire is energy.
2. A candle flame is caused by vapour burning above the candle. This burning vapour is hotter than the surrounding air and is therefore high dense. So, by the principle of reduction, it “rises” so the flame is always upwards.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

Explanation

Flame is actually a chemical reaction. To be specific, the flame is a mixture of gases (vaporized fuel, oxygen, carbon dioxide, carbon monoxide, water vapor, and many volatile materials) and so is matter. The light and heat produced by the flame is energy, not matter. But fire is a matter.

A candle flame is caused by vapour burning above the candle. This burning vapour is hotter than the surrounding air and is therefore less dense. So, by the principle of convection, it “rises” so the flame is always upwards.

54. Which among the following do not produce flames?

1. Wax
2. Kerosene
3. Coal
4. None of the above

Explanation

Substances which do not vaporize during burning do not produce flames e g. coal. Wax and Kerosene produce flame.

55. Match the following salts correctly with its flame colour?

1. Epsom salt – 1. Violet flame
2. Lithium Chloride – 2. Green flame
3. Bleaching powder – 3. White flame
4. Borax powder – 4. Blue flame
5. Calcium chloride – 5. Yellow flame
6. 1 – 3 – 2 – 5 – 4
7. 3 – 1 – 4 – 2 – 5
8. 2 – 5 – 3 – 1 – 2
9. 4 – 1 – 2 – 5 – 1

Explanation

White flame – Epsom salt (MgSO4 ) • Violet flame – Lithium Chloride • Blue flame – Bleaching powder • Green flame – Borax powder • Yellow flame – Calcium chloride.

56. Which among the following statement is correct regarding candle flame

1. The outer zone: partial combustions of the fuel take place and the colour of the flame is yellow and is moderately hot part of the flame. It is the luminous part of the flame.
2. The middle zone: complete combustion of the fuel takes place and the colour of the flame is blue and is the hottest part of the flame. It is the non-luminous part of the flame.
3. The inner zone: There are unburnt vapours of the fuel and the colour is black and is least hot part.
4. Only 1
5. Only 3
6. Both 1 and 2
7. Both 2 and 3

Explanation

The outer zone – complete combustion of the fuel takes place and the colour of the flame is blue and is the hottest part of the flame. It is the non-luminous part of the flame.

The middle zone -partial combustions of the fuel takes place and the colour of the flame is yellow and is moderately hot part of the flame. It is the luminous part of the flame.

57. The amount of heat energy produced on complete combustion of 1kg of fuel is called its _________

1. Thermal value
2. Burner value
3. Calorific value
4. Toaster value

Explanation

The amount of heat energy produced on complete combustion of 1kg of fuel is called its calorific value.

58. What will be the colour of flame if table salt soaked in alcohol and makes fire?

1. Green flame
2. White flame
3. Orange flame
4. Pink flame

Explanation

Table salt produce orange flame if soaked in alcohol and makes fire.

59. The calorific value of a fuel is expressed in a unit called _________

1. J / kg
2. KJ / kg
3. KJ Kg
4. Kg / J

Explanation

The calorific value of a fuel is expressed in a unit called kilo joule per kg (kJ/kg).

60. Which among the following equation is correct regarding calorific value?

1. Calorific value = Amount of fuel used for burning in kJ/kg / Heat produced
2. Calorific value = Heat produced / Amount of fuel used for burning in kJ/kg
3. Calorific value = Amount of fuel used for burning in kJ/kg × Heat produced
4. Calorific value = Amount of fuel used for burning in kJ/kg – Heat produced

Explanation

Calorific value = Amount of fuel used for burning in kJ/kg × Heat produced.

If 4.5kg of fuel is completely burnt and the amount of heat produced stands measured at 1, 80,000 kJ what is its calorific value. Calorific value = 1, 80,000 / 4.5 = 40,000 KJ/Kg.

61. What will be the colour of flame if Strontium chloride soaked in alcohol and makes fire?

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

Explanation

Strontium chloride produce red flame if soaked in alcohol and makes fire. Potassium Chloride produce Indigo Flame.

62. Which among the following is not the types of combustion?

1. Rapid combustion
2. Cold combustion
3. Spontaneous combustion
4. None of the above

Explanation

There are three main types of combustion. They are, 1. Rapid combustion, 2. Spontaneous combustion and 3. Explosion.

63. Which among the following statement is correct

1. Rapid combustion: It is a combustion process in which a substance burns rapidly and produces heat and light with the help of external heat. E.g. Burning of LPG.
2. Spontaneous combustion: Is combustion process in which a light with the help of external heat.eg. Phosphorus burns spontaneously at high temperature.
3. Explosion: It is a type of combustion in which a substance burns suddenly and produces heat, light and sound with the help of heat or pressure. E.g. Explosion of crackers.
4. Both 1 and 2
5. Both 1 and 3
6. Both 2 and 3
7. All 1, 2 and 3

Explanation

Spontaneous combustion: Is combustion process in which a light without the help of external heat.eg. Phosphorus burns spontaneously at room temperature.

64. Which among the following has the highest calorific value?

1. Kerosene
2. Biogas
3. Petrol
4. Methane

Explanation

Methane (500000) has highest calorific value followed by diesel (450000) and hydrogen (150000).

65. Which among the following is not the Characteristics of good fuel?

1. Cheap
2. Produce large amount of heat
3. Easy transport and store
4. Leave behind undesirable substances

Explanation

Characteristics of good fuel are 1. Readily available 2. Cheap 3. Easy transport and store 4. Burns at moderate rate 5. Produce large amount of heat 6. Do not leave behind any undesirable substances. And 7. Does not cause pollution.

66. Respiration is an example of which combustion?

1. Slow combustion
2. Spontaneous combustion
3. Rapid combustion
4. None of the above

Explanation

Slow combustion is a form of combustion which takes place at low temperatures. Respiration is an example of slow combustion.

67. Which among the following is not the condition necessary for producing fire?

1. Fuel
2. Air (to supply oxygen)
3. Heat (to raise the temperature of the fuel beyond its ignition temperature)
4. None of the above

Explanation

Th e conditions necessary for producing fire are, 1. Fuel 2. Air (to supply oxygen) and 3. Heat (to raise the temperature of the fuel beyond its ignition temperature). Fire can be controlled by removing any one or more of these conditions.

68. Which among the following fuel has the lowest calorific value?

1. Wood
2. Cow dung cake
3. Petrol
4. Biogas

Explanation

69. Which among the following statement is correct

1. A fire extinguisher cut off the supply of Air or bring down the temperature of the fuel or both and controls the fire. Portable fire extinguishers apply an extinguishing agent that will either cool burning fuel, displace or remove oxygen, or stop the chemical reaction so fire cannot continue to burn.
2. When the candle of an extinguisher is compressed, it opens and inner canister of high-pressure gases forces the extinguishing agent from the main cylinder through a siphon tube and out the nozzle. A fire extinguisher works much like a can of hair spray.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

70. Which among the following is not the common types of fire extinguishers?

1. Sand soluble extinguisher
2. Air pressurized water extinguishers
3. Carbon-di-oxide extinguishers
4. Dry chemical powder extinguishers

Explanation

The most common types of fire extinguishers are, 1. Air pressurized water extinguishers, 2. Carbon-di-oxide extinguishers and 3. Dry chemical powder extinguishers.

71. Which among the following is not the combustible materials?

1. Wood
2. Paint
3. Paper
4. Fabric

Explanation

Combustible materials: caused by flammable solids, such as wood, paper, and fabric.

72. Which among the following is not the Flammable gases?

1. Hydrogen
2. Butane
3. Potassium
4. Methane

Explanation

Flammable gases: like hydrogen, butane or methane.

73. Which among the following is not the Flammable liquid?

1. Petrol
2. Magnesium
3. Paint
4. None of the above

Explanation

Flammable liquids: such as petrol, turpentine or paint.

74. Fire extinguishers can be broadly classified into how many types?

1. Two
2. Three
3. Four
4. Five

Explanation

Fire extinguishers can be broadly classified into five types: 1. Water, 2. Foam, 3. Dry Powder, 4. CO2, 5. Wet Chemical.

75. Which among the following is not combustible metals?

1. Magnesium
2. Aluminium
3. Potassium
4. None of the above

Explanation

Combustible metals: chemicals such as magnesium, aluminium or potassium.

76. Which among the following class of fire is wrongly matched?

1. Class A – Combustible materials
2. Class B – Flammable gases
3. Class C – Flammable liquids
4. Class D – Combustible metals
5. Both 1 and 2
6. Both 1 and 3
7. Both 2 and 3
8. Both 3 and 4

Explanation

There are five classes of fire: Class A, Class B, Class C, Class D, and Class E.

7th Science Lesson 16 Questions in English

16] Animals in Daily Life

1. Which is the primary source of nutrition for infant mammals?

1. Egg
2. Grains
3. Milk
4. All the above

Explanation

Milk is white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for infant mammals. We use milk in our daily life for the following. Milk is the daily essential product which is obtained from animals like cows, buffaloes goats and camels.

2. Which among the following is not made up of Milk?

1. Panner
2. Butter
3. Mayonnaise
4. Ghee

Explanation

Milk is necessary in our daily diet to prepare tea, coffee, ice creams, chocolates, sweets and other related products. Highly recommended nutritive food containing protein and calcium are made from milk like, Paneer, Cheese, Cream, Butter, Ghee and curd.

3. Which among the following does not lay egg?

1. Rooster
2. Hen
3. Turkey
4. Ostrich

Explanation

Eggs are laid by female birds of many different species to produce their young ones like hen, duck, turkey and ostrich. We use these in our daily life for the following. They are used in our daily diet to get energy and good health. It is highly nutritious and rich in protein.

4. Eggs have how many grams of high-quality protein?

1. 4 grams
2. 6 grams
3. 8 grams
4. 12 grams

Explanation

Eggs have 6 grams of high-quality protein. A protein packed breakfast helps to sustain mental and physical energy throughout the day. Consuming egg daily is good for any age people.

5. Which among the following statement is correct

1. Bees collect nectar (sweet juices) from flowers, convert it into honey and store in their honey comb. Honey is a sweet liquid produced by honey bees from the nectar of flowers. It is extracted from beehives by us.
2. Raw organic wild honey is extracted from selected hives by tribal honey hunters, who collect it from jungles. Honey has more medicinal values and highly nutritious food.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

6. Who among the following collect the nectar from the flowers?

1. Worker bees
2. Queen bees
3. Male bees
4. All the above

Explanation

The worker bees collect the nectar from the flowers. They nourish the young ones and repair the bee hive and also protect it.

7. Which among the following animal meat is called beef?

1. Sheep
2. Rabbit
3. Camel
4. Buffalo

Explanation

Meat is animal flesh that is eaten as food. Most often it is used to describe skeletal muscle and fat that is found with it. Some people eat the flesh of animals such as chicken, sheep, rabbit, pig, goat, camel, buffalo (beef), fish, crab, prawn, lobster and many more.

8. Which breeding is done in large scale in the form of poultry farming for economic purpose?

1. Pig
2. Chicken
3. Goat
4. Crab

Explanation

Animal meat is considered as the part of diet by most of the people. Meat consumption is considered essential for its nutritive values. Especially chicken breeding is done in large scale in the form of poultry farming for economic purpose.

9. Which among the following is not domesticated in poultry farming?

1. Chicken
2. Pig
3. Duck
4. Turkey

Explanation

Poultry farming is the process of raising domesticated birds such as chicken, duck, turkey and geese for the purpose of getting meat and egg for food.

10. Chickens are broadly of how many types?

1. Two
2. Three
3. Four
4. Five

Explanation

Poultries are reared in large numbers and chickens being the most common one. Chickens are broadly of two types. 1. Layers (egg laying chickens) 2. Broilers (one’s that are reared for meat).

11. Which among the following is not the poultry feed?

1. Maize
2. Ricin
3. Millet
4. Ground nut cates

Explanation

Poultry farming requires safe and sufficient space (wired gages) for the birds. Plenty of water, proper ventilation and regular feed that is rich in proteins, fats and vitamins. Poultry feed is comprised of maize, wheat, millet and rice bran in mashed form and ground nut cakes.

12. The disease Salmonellosis is caused by which among the following microscopic organism?

1. Virus
2. Bacteria
3. Fungus
4. All the above

Explanation

Poultry birds suffer from various diseases caused by some microbes. It is important to keep their shelters clean and get the birds vaccinated against common diseases. Salmonellosis (diarrhoea) Caused by bacteria.

13. Aspergilleses is a disease caused by which among the following?

1. Virus
2. Bacteria
3. Fungus
4. Protists

Explanation

Aspergilleses is a poultry disease Caused by fungus.

14. Ranikhat disease is a poultry disease caused by what?

1. Virus
2. Bacteria
3. Fungus
4. Protists

Explanation

Ranikhat disease, (Fowl pox) is a poultry disease caused by virus.

15. Which among the following animal hair is not used for manufacturing woollen clothes, shawls and blankets, mufflers and socks?

1. Goat
2. Sheep
3. Pig
4. None of the above

Explanation

Animal hair has a great demand. Th e hair from goat and sheep is used for manufacturing woollen clothes, shawls and blankets, mufflers and socks.

16. Which animal hair is used as bristles in small painting brushes?

1. Pig hair
2. Horse hair
3. Elephant hair
4. Bull hair

Explanation

Horse hair is used as bristles in small painting brushes. Even fur of animals including the skin is used to make warm and modern style clothes.

17. Which among the following is called natural fibres?

1. Cotton
2. Jute
3. Silk
4. All the above

Explanation

Some fabric fibres such as cotton, jute, silks are called natural fibres.

18. Which among the following is not the plant fibre?

1. Cotton
2. Jute
3. Silk
4. None of the above

Explanation

Cotton and jute are examples of plant fibres. Wool and silk fibres are examples of animal fibres.

19. Wool is not obtained from which among the following animals?

1. Sheep
2. Yak
3. Rabbit
4. None of the above

Explanation

Wool is obtained from the fleece of sheep or goat. It is also obtained from the hair of rabbit, yak and camel. Silk fibre is obtained from the cocoon of silkworm.

20. Wool is the fibre derived from the fur of animals of which family?

1. Caprinae family
2. Felidae family
3. Canidae family
4. Gavialidae family

Explanation

Wool is the fibre derived from the fur of animals of the Caprinae family principally sheep. Th e hair of other mammals like goat, yak, alpaca and rabbit may also be called wool. Mostly, wool is produced from the outer coat of sheep.

21. The processing of wool involves how many major steps?

1. Two
2. Three
3. Four
4. Five

Explanation

The processing of wool involves five major steps. They are as follows Shearing, Grading, washing, Carding and Spinning.

22. The fleece from the same sheep may be different from different parts of the body and sorted out into separate piles of similar nature. This is known as __________

1. Grading
2. Shearing
3. Carding
4. Spinning

Explanation

The fleece from the same sheep may be different from different parts of the body. It is sorted out into separate piles of similar nature. This is known as Grading (or) Sorting.

23. The flesh of the sheep is removed from its body. This is called _____

1. Sorting
2. Scouting
3. Carding
4. Shearing

Explanation

The flesh of the sheep is removed from its body. This is called shearing.

24. The sheared skin is washed thoroughly with what to remove dirt?

1. Soap
2. Blood
3. Table salt
4. All the above

Explanation

The sheared skin is washed thoroughly with soap (or) detergents to remove dirt, dust and grease. This is called Washing (or) Scouting.

25. Which among the following statement is correct

1. Carding: – The dried wool is carefully removed. These fibres then passed through the rollers which are covered with fine sheet of thin wire teeth. This process arranges the wool into a flat sheet called a web.
2. Spinning: – The web is drawn into narrow strand and then passed through spinning machines. The spinning machines twist the strands into yarn. The yarn is wound to form balls of wool. This yarn is either weaved into fabric (or) retained for knitting.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

26. Which among the following is not the Characteristic features of wool?

1. It is resistant to heat, water, wear and tear.
2. It does not absorb moisture.
3. Wool insulates against cold. So wool is a good insulator.
4. It does not wrinkle easily.

Explanation

Characteristic features of wool 1. It is resistant to heat, water, wear and tear. 2. It absorbs moisture. 3. Wool insulates against cold. So wool is a good insulator. And 4. It does not wrinkle easily.

27. Silk worms pass through how many stages of development?

1. Two
2. Three
3. Four
4. Five

Explanation

Silk worms live for a very short time, only about two months. During this period, they pass through four stages of development. They are eggs, caterpillars, cocoon and adult moth. These stages are called as life cycle of a silk worm.

28. Silk is obtained from which stage of silk worms?

1. Eggs
2. Caterpillars
3. Cocoon
4. Adult moth

Explanation

Silk is the secretions of the silk moth. Silk is obtained from the cocoon of silk worms.

29. Silk worms predominantly feed on which among the following leaves?

1. Mulberry leaves
2. Legumes leaves
3. Willow leaves
4. Parsley leaves

Explanation

Silk is obtained from the cocoon of silk worms, which feed on the mulberry leaves.

30. The cultivation and production of silk is known as _____

1. Silviculture
2. Horticulture
3. Sericulture
4. Apiculture

Explanation

The cultivation and production of silk is known as Sericulture. Sericulture or silk farming is the cultivation of silk worm to produce silk. It is the rearing of silk worms to obtain silk.

31. An adult female silk moth lays about how many eggs?

1. 100
2. 200
3. 500
4. 800

Explanation

An adult female silk moth lays about 500 eggs.

32. Which among the following statement is correct

1. An adult female silk moth lays about 500 eggs. The eggs are then kept in cold storage for two weeks. The eggs are placed in the incubator. After about six days, the eggs hatch out and the larvae spend the next 15 days eating mulberry leaves.
2. The silk worms spend about five days producing silk and spinning its cocoon of a single long thread. The cocoons are boiled to make it easier to unwind the silk and kill the pupae inside. If the silk moths were allowed to hatch, the long silk fibres will get turned by the hatching of moth
3. Cocoons are unwind and then the individual silk filament is reeled together to form a thread large enough for weaving. The silk thread is cleaned, dyed, woven into fabric.
4. Only 1
5. Only 2
6. Both 1 and 2
7. Both 2 and 3

Explanation

An adult female silk moth lays about 500 eggs. The eggs are then kept in cold storage for six weeks. The eggs are placed in the incubator. After about ten days, the eggs hatch out and the larvae spend the next 35 days eating mulberry leaves.

33. Which among the following is not the characteristic feature of silk?

1. It is very soft, comfortable and versatile
2. It can be easily dyed
3. It is the strongest natural fibre
4. It has a high resistance to sunlight exposure

Explanation

Characteristic features of Silk are 1. It is very soft , comfortable and versatile 2. It can be easily dyed. 3. It is the strongest natural fibre. 4. It has a poor resistance to sunlight exposure.

34. Which among the following statement is correct

1. Wool is a multifunctional fibre with a range of diameters that makes it suitable for clothing, household fabrics and technical textiles. Two third of wool is used in the manufacture of garments including sweaters, dresses, coats and active sportswear. Blended with other natural (or) synthetic fibres wool used as adds drape and crease resistance blankets, anti-static and noise absorbing carpets.
2. Silk has natural beauty and elegance. It gives comfort in cold weather and cold during summer months. It is used in the manufacture of classical and high fashion clothes, modern dresses particularly silk sarees, the elegant of beautiful dresses. It is also used in household for making wall hangings, curtains, rugs and carpets. It is also being used in the manufacture of Cyborg for its hard nature.
3. Only 1
4. Only 2
5. Both 1 and 2
6. None

Explanation

Silk has natural beauty and elegance. It gives comfort in warm weather and warmth during colder months. It is used in the manufacture of classical and high fashion clothes, modern dresses particularly silk sarees, the elegant of beautiful dresses. It is also used in household for making wall hangings, curtains, rugs and carpets. It is also being used in the manufacture of surgical threads for sutures.

35. What is the position of India in silk production in world?

1. First
2. Second
3. Three
4. Five

Explanation

India is the world’s second largest silk producing country.

36. Which among the following is not the famous places for silk production in Tamil Nadu?

1. Kancheepuram
2. Thirubhuvanam
3. Tirupathur
4. Arani

Explanation

Kancheepuram, Thirubhuvanam and Arani are famous places for silk production in Tamil Nadu.

37. Which is any industry has the potential to cause injury, ill health or damage to human being and their property or the environment?

1. Hazard
2. Development
3. Capital
4. None of the above

Explanation

Hazard is any industry has the potential to cause injury, ill health or damage to human being and their property or the environment.

38. The workers in silk industry affected with what as they stand for a long time reeling the silk into yarn?

1. Bronchitis
2. Skin injury
3. Arthritis
4. All the above

Explanation

Generally, the workers in silk industry affected with arthritis is they stand for a long time reeling the silk into yarn. They also develop back pain and visionary problem and skin injuries. Some time they may suffer from respiratory problem like asthma and bronchitis due to poor ventilated area of their work.

39. Which is caused by Bacillus anthracis by handling contaminated animal hair and contact with the live stock during hair processing?

1. Cholera
2. Syphilis
3. Plague
4. Anthrax

Explanation

Anthrax is caused by Bacillus anthracis by handling contaminated animal hair and contact with the live stock during hair processing.

40. Which among the following is not the symptoms of anthrax?

1. Fever
2. Cough
3. Blood in urine
4. Vomiting

Explanation

Anthrax symptoms are fever, cough and shortness of breath, similar to a typical pneumonia. Sometimes it may lead to nausea, vomiting and diarrhoea.

41. Which is given as the best medicine for treatment of anthrax?

1. Ciprofloxacin
2. Amoxicillin
3. Diphenhydramine,
4. Ibuprofen

Explanation

Penicillin or Ciprofloxacin is given as the best medicine for treatment of anthrax. The spread of the disease is controlled by vaccination of animals and by burning or burial of infected animal’s carcases. It is the duty of the employer to take care of the industrial workers by providing hygienic and well-ventilated work place.

42. Workers in wool industry also get infected to anthrax bacterium which leads to fatal dead disease called _________

1. Syphilis disease
2. Cholera
3. Sorters disease
4. Diphtheria disease

Explanation

Hazards in wool industry the workers are exposed to various chemicals and detergents which causes allergies of the skin. They also get infected to anthrax bacterium which leads to fatal dead disease called the sorters disease.

43. Which among the following is not the type of wool?

1. Eri
2. Alpaca
3. Fibre
4. Cashmere

Explanation

The types of wool are Alpaca, Fiber, Moheir, Cashmere and Lambs Wool.

44. Which among the following is not the type of silk?

1. Eri silk
2. Muga
3. Spider silk
4. Moheir

Explanation

The types of silks are Eri Silk, Muga and Spider Silk.

45. Ahimsa silk is also known as _________

1. Gandhi silk
2. Peace silk
3. White silk
4. All the above

Explanation

Ahimsa silk is also known as Peace silk.

46. In 1992, who proposed ahimsa way of silk production for the making silks without killing the silkworm?

1. Padmaja Naidu
2. Tanguturi Prakasam
3. Kusuma Rajaiah
4. Muktyala Raja

Explanation

In 1992, Kusuma Rajaiah proposed ahimsa way of silk production for the making silks without killing the silkworm. It involves a humane method specifically letting the worms to hatch and then using the vacant cocoons.

47. Kusuma Rajaiah is from which among the following state?

1. Kerala
2. Andhra Pradesh
3. Odisha
4. Himachal Pradesh

Explanation

In 1992, Kusuma Rajaiah, a Government officer from Andhra Pradesh state of India proposed ahimsa way of silk production for the making silks without killing the silkworm. Traditional silk manufacturing methods involve boiling the cocoons of the silk worms and then sorting out the threads, which is used later in silk production. It has been supported by many people who are interested in the welfare of animals.

48. Study of breeding of animals and their maintenance is ________

1. Animal Husbandry
2. Animal Horticulture
3. Animal Apiculture
4. Animal Pisciculture

Explanation

Study of breeding of animals and their maintenance is called Animal Husbandry. Protecting animals is like protecting our own children or parent. They are living things similar to human beings. The human tendency and conscience towards the animals should be considerate to protect and safe guard the animals, hence as human it becomes a great responsibility and obligatory to protect the animals.

49. Prevention of Cruelty to Animals Act was enacted in which among the following year?

1. 1948
2. 1953
3. 1960
4. 1979

Explanation

The Prevention of Cruelty to Animals Act was enacted in 1960.

50. The Ministry of Environment, Forest and Climate change has released how many New Gazette Notifications under the Prevention of Cruelty to Animals Act 1960 to regulate dog breeders, animal marketers, aquarium and pet fish owners?

1. Two
2. Three
3. Four
4. Six

Explanation

The Ministry of Environment, Forest and Climate change has released four New Gazette Notifications under the Prevention of Cruelty to Animals Act 1960 to regulate dog breeders, animal marketers, aquarium and pet fish owners. This progress has come about as a joint effort by animal protection groups. With the protection of animal we actually protect ourselves and protect the environment. So, we have to love and protect the animals and treat them as our family members.