62 important questions on Biology (Answered)

1. Which is the basic requirement of living organisms for obtaining energy?

2. Which of the following type of energy is used by living organisms to perform vital life processes? Kinetic energy, Chemical energy, Potential energy, Nuclear energy

3. Which of the following is an autotroph? Green plant or Man

4. Name two inorganic substances which are used by autotrophs to make food.

5. What is the mode of nutrition in fungi?

6. Name one organism each having saprophytic, parasitic and holozoic modes of nutrition.

7. Name the process by which plants make food.

8. In addition to carbon dioxide and water, state two other conditions necessary for the process of photosynthesis to take place.

9. Apart from sunlight and chlorophyll, what other things are required to make food by photosynthesis?

10. (a) Name a gas used in photosynthesis.

(b) Name a gas produced in photosynthesis.

11. The leaves of a plant first prepare food A by photosynthesis. Food A then gets converted into food B. What are A and B?

12. Which substance is used to remove chlorophyll from a green leaf during photosynthesis experiments?

13. Why do we boil the leaf in alcohol when we are testing it for starch?

14. (a) Name the pigment in leaves which absorbs sunlight energy.

(b) What is the colour of this pigment?

15. Name the pigment which can absorb solar energy.

16. Name the organelle of plant cells in which photosynthesis occurs.

17. Apart from carbon dioxide and water, name four other raw materials which are needed by the plants.

18. Where is chlorophyll mainly present in a plant?

19. What is the name of those cells in the leaf of a plant which control the opening and closing of stomata?

20. Name an animal whose process of obtaining food is called phagocytosis.

21. All the animals can be divided into three groups on the basis of their eating habits. Name the three groups.

22. What is the scientific name of the animals which are?

(i) Only meat eaters?

(ii) Only plant eaters?

(iii) Both, plant and meat eaters?

23. Name the green pigment present in the leaves of a plant.

24. Arrange the following processes involved in the nutrition in animals in the correct order (in which they take place):

Assimilation, Egestion, Ingestion, Absorption, Digestion

25. How does Amoeba engulf the food particle?

26. What substances enter into the food vacuole in Amoeba to break down the food?

27. From which part of the body, undigested food is egested in Amoeba?

28. Name a unicellular animal which uses cilia to move food particles into its mouth.

29. Name the enzyme present in human saliva. What type of food material is digested by this enzyme?

30. Which of the organs perform the following functions in humans?

(i) Absorption of food

(ii) Absorption of water

31. What moves the food in the digestive organs?

32. What is the other name of food pipe?

33. What substance is mixed with food in the mouth during chewing by the teeth?

34. What is the name of tiny projections on the inner surface of small intestine which help in absorbing digested food?

35. In which part of the digestive system is water absorbed?

36. What is the name of the opening in the human body through which undigested food is thrown out?

37. Where is digested food absorbed into blood in human body?

38. Name the biological catalysts which bring about chemical digestion of food.

39. Fill in the following blanks with suitable words:

(a) All green plants are………

(b) All non-green plants and animals are…

(c) Heterotrophs depend on…. and other…………. for food.

(d) Green plants use……………..and……….. to make food.

(e) Iodine turns blue-black on reacting with……….

40. (a) What is chlorophyll? What part does chlorophyll play in photosynthesis?

(b) (i) Which simple food is prepared first in the process of photosynthesis?

(ii) Name the food which gets stored in plant leaves.

41. (a) What criteria can be used to decide whether something is alive?

(b) What is meant by life processes? Name the basic life processes common to all living organisms which are essential for maintaining life.

42. (a) What are autotrophs? Give one example of autotrophs.

(b) What are the conditions necessary for autotrophic nutrition?

43. (a) What are heterotrophs? Give one example of heterotrophs.

(b) What is the difference between autotrophic nutrition and heterotrophic nutrition?

44. (a) Define a nutrient. Name four important nutrients present in our food.

(b) What are the various types of heterotrophic nutrition?

45. (a) Photosynthesis converts energy X into energy Y. What are X and Y?

(b) State the various steps involved in the process of photosynthesis.

46. (a) How do plants obtain food?

(b) Why do plants need nitrogen? How do plants obtain nitrogen?

47. Define (i) saprophytic nutrition (it) parasitic nutrition, and (Hi) holozoic nutrition. Give one example of each type.

48. Define (i) saprophyte, and (ii) parasite. Name two saprophytes and two parasites.

49. (a) How does carbon dioxide from the air enter the leaves of a plant to be used in photosynthesis? (b) How does water from the soil reach the leaves of a plant to be used in photosynthesis?

50. What substances are contained in gastric juice? What are their functions?

51. What substances are contained in pancreatic juice? What are their functions?

52. (a) What is the role of hydrochloric acid in our stomach?

(b) What is the function of enzymes in the human digestive system?

53. (a) Which part of the body secretes bile? Where is bile stored? What is the function of bile?

(b) What is trypsin? What is its function?

54. What are the functions of liver and pancreas in the human digestive system?

55. Match the organisms given in column I with the processes given in column II:

56. Name the following:

(a) The process in plants which converts light energy into chemical energy.

(b) Organisms that cannot prepare their own food.

(c) Organisms that can prepare their own food.

(d) The cell organelle where photosynthesis occurs.

(e) The cells which surround a stomatal pore.

(f) An enzyme secreted by gastric glands in stomach which acts on proteins.

57. Match the terms in column I with those in column II:

Column I

(i) Trypsin

(ii) Amylase

(iii) Bile

(iv) Pepsin

Column II

(a) Liver

(b) Gastric glands

(c) Pancreas

(d) Saliva

58. (a) What is common for Cuscuta, ticks and leeches?

(b) Name the substances on which the following enzymes act m the human digestive system:

(i) Trypsin (ii) Amylase (iii) Pepsin (iv) Lipase

(c) Why does absorption of digested food occur mainly in the small intestine?

59. (a) Why is small intestine in herbivores longer than in carnivores?

(b) What will happen if mucus is not secreted by the gastric glands?

(c) What causes movement of food inside the alimentary canal?

60. (a) How do guard cells regulate opening and closing of stomatal pores?

(b) Two similar green plants are kept separately in oxygen free containers, one in dark and the other in continuous light. Which one will live longer? Give reasons.

61. (a) What would happen if all the green plants disappear from the earth?

(b) If a plant is releasing carbon dioxide and taking in oxygen during the day, does it mean that there is no photosynthesis occurring? Justify your answer.

62. (a) Leaves of a healthy potted plant were coated with Vaseline. Will this plant remain healthy for long? Give reason for your answer.

(b) What will happen to the rate of photosynthesis in a plant under the following circumstances?

(i) cloudy day in morning but bright sunshine in the afternoon

(ii) no rainfall in the area for a considerable time.

(iii) gathering of dust on the leaves.

Answer

1. Food 2. Chemical energy 3. Green plant 10. (a) Carbon dioxide (b) Oxygen 11. A is glucose ; B is starch 19. Guard cells 20. Amoeba 31. Peristaltic movement 39. (a) autotrophs (b) heterotrophs (c) plants ; animals (d) carbon dioxide, water, sunlight (e) starch 40. (b) (i) Glucose (ii) Starch 45. (a) X : Light energy ; Y : Chemical energy 55 (i) c (ii) a (iii) d (iv) b 56 (a) Photosynthesis (b) Heterotrophs (c) Autotrophs (d) Chloroplast (e) Guard cells if) Pepsin 57. (i) c (ii) d (iii) a (iv) s 58. (a) Parasitic mode of nutrition (b) (i) Proteins (ii) Starch (iii) Proteins (iv) Fats (c) Due to the presence of a large number of villi 60. (b) Plant kept in continuous light will live longer because it will be able to produce oxygen required for its respiration by the process of photosynthesis . (a) Green plants are the source of food for all the organisms. If all the green plants disappear from the earth, then all the organisms (herbivores, carnivores and omnivores) will die due to starvation (b) When photosynthesis occurs during, the day, the carbon dioxide released by plants by respiration is all used up and not released. Similarly, some of the oxygen produced during photosynthesis is used up in respiration. Since the plant here is releasing carbon dioxide and taking in oxygen even during the day, it means that no photosynthesis is taking place 62. (a) This plant will not remain healthy for long because Vaseline coating closes the stomatal pores on the leaves due to which (i) plant will not get oxygen for respiration (ii) plant will not get carbon dioxide for photosynthesis, and (iii) plant will not get water (and minerals) due to stoppage of transpiration (b) (i) Decreases in morning but increases in the afternoon (ii) Decreases (iii) Decreases