SCIENCE 7 SOLUTION CHAPTER - 2

  Chapter-2   Nutrition in Animals

NCERT EXERCISE QUESTIONS AND ANSWERS

1. Fill in the blanks:

(a) The main steps of nutrition in humans are ___________, ___________, ___________ ,

___________ and ___________

(b) The largest gland in the human body is ___________.

(c) The stomach releases hydrochloric acid and ___________ juices which act on food.

(d) The inner wall of the small intestine has many finger-like outgrowths called

___________

(e) Amoeba digests its food in the ___________ .

Answer:

(a) ingestion, digestion, absorption, assimilation, egestion

(b) liver

(c) digestive

(d) villi

(e) food vacuole.

2. Mark ‘T’ if the statement is true and ‘F’ if it is false:

(a) Digestion of starch starts in the stomach.

(b) The tongue helps in mixing food with saliva.

(c) The gall bladder temporarily stores bile.

(d) The ruminants bring back swallowed grass into their mouth and chew it for some time.

Answer: a) F (b) T (c) T (d) T

3. Tick (√) mark the correct answer in each of the following:

(a) Fat is completely digested in the

(i) stomach

(ii) mouth

(iii) small intestine

(iv) large intestine

(b) Water from the undigested food is absorbed mainly in the:

(i) Stomach

(ii) Food pipe

(iii) Small intestine

(iv) Large intestine

Answer. (a) (iii) Small intestine (b) (iv) Large intestine

4. What are villi? What is their location and function?

Answer: The finger like projections in the inner walls of the small intestine is called villi.

These are found in small intestine.

Function: The villi increase the surface area for absorption of the digested food

5. Where is the bile produced? Which component of the food does it help to digest?

Answer: Bile is produced in liver. The bile juice stored in sac called the gall bladder. It

helps in the digestion of fats.

6. Name the type of carbohydrate that can be digested by ruminants but not by humans.

Give the reason also.

Answer: Cellulose is the carbohydrate that can be digested by ruminants. Ruminants have

large sac like structure between the small intestine and large intestine. The cellulose of the

food is digested by the action of certain bacteria which are not present in humans.

7. Why do we get instant energy from glucose?

Answer: We get instant energy from glucose because it easily breaks down in the cell with

the help of oxygen which provides instant energy to the organism. Glucose does not need to

go through the process of digestion; it is directly absorbed into the blood.

8. Which part of the digestive canal is involved in:

(i) Absorption of food ________ .

(ii) Chewing of food ________ .

(iii) Killing of bacteria ________ .

(iv) Complete digestion of food ________ .

(v) Formation of faeces ________ .

Answer: (i) Small intestine (ii) Mouth (iii) Stomach (iv) Small intestine (v) Large intestine

9. Write one similarity and one difference between the nutrition in amoeba and human

beings.

Answer: Similarity: In both amoeba and human beings digestive juices break down the

complex food particles into simpler substances that can be absorbed.

Difference: Amoeba has no mouth and no digestive system whereas human beings has a

mouth and a complex digestive system made up of many organs.

10. Label the below given figure of the Human digestive system.

Answer:

1. Fill in the Blanks: (a) During the process of digestion carbohydrates are broken down into _________

(b) During digestion Complex substance are broken down into ________(c) The organ that stores bile is _________ (d) In human beings most of the nutrients are absorbed by the _________ (e) The inner walls of the stomach secrete _________ (f) After chewing an apple, the crushed Apple is swallowed and passed from the _________

(g) The bile helps in the breakdown of _________ 

(h) Amoeba takes in food by the use of _________ (i) The engulfed food in Amoeba is trapped in the _________ (j) The digested food moves from the stomach to the _________ (k) During digestion proteins are broken down into _________ (l) Pancreas is located just below the _________ (m)Excess water in the food is absorbed in the _________ (n) Grass is rich in carbohydrates known as _________

(o) The digestive juice that begins the digestion of carbohydrate is _________ .

(p) The semi digested food in the stomach called _________ 

(q) The digestion of food completed in _________ 

(r) During digestion fat is broken down into _________ 

(s) Glucose combines with oxygen and produces _________ 

(t) The process by which a living cell releases energy from glucose is called _________

9. Give one instant source of carbohydrate? 

10. Where the digestion does starts? 

11. What is not digested by human? 

12. Name the glands present in the mouth.  

13. Where is bile produced? 

14. Name the process of taking in food? 

15. What helps the food to taste it by our tongue? 

16. Name the largest gland in human body. 

17. Which part of Amoeba helps in capturing the food particles? 

18. Name the organ that helps in nutrition in Hydra? 

19. Which organ is known as the food pipe? 

20. What is Digestion? 

21. Where is the bile produced? Which component of the food does it digest?

22. Name the type of carbohydrate that can be digested by ruminants but not by humans. Give  the reason also. 

23. Write one similarity and one difference between the nutrition in amoeba and human beings.

24. What is Absorption?  

25. Why do we get instant energy from glucose?  

26. What is salivary digestion? 

27. What are parasites? 

28. Name the various digestive organs of man? 

29. What is cellouse? 

30. What is the function of premolars and molars? Write the number of both teeth in each jaw

31. Which teeth do you use for piercing and tearing? Write the number of these teeth.  32. How many types of teeth do you find in humans? Name them. 

33. What are the main steps of digestion in humans?  

34. Name the type of food and mode of feeding of the following animals- (a)Ant (b)Mosquito 

Short Answer Type Questions 

35. What is digestion? 

36. Write the function of the tongue? 

37. Where is saliva produced? 

38. Name the organs of the human digestive system? 

39. Name the different types of teeth found in human beings? 

40. Give an example of ruminants? 

41. What is peristalsis? 

42. What are villi? What is their location and function? 

43. Why do we get instant energy from glucose? 

44. Can we survive only on raw, leafy vegetables/grass? Discuss. 

45. Where are the salivary glands located and what is their functions? 

46. Explain the term Assimilation, Pseudopodia? 

47. What do you understand by rumen and rumination? 

48. Write the functions of the tongue. 

49. What is the difference between milk teeth and permanent teeth? 

50. Differentiate between incisors and canines? 

51. Name the acid produced in the stomach? 

52. Name any one digestive juice and describe its role in digestion? 

53. How does the liver help in the digestion of food? 

54. What is rumination? 

Long Answer Type Questions 

55. Draw and label Digestive system, of ruminant? 

56. Draw and label Human Digestive system? 

57. Explains with diagram Feeding System in Amoeba? 

58. Explains the Effect of Saliva on starch? 

59. Write the process absorption food in the small intestine? 

60. Draw labelled diagrams of (a) Regions of the tongue for different tastes (b)Amoeba 61. Write short notes on: (a) The stomach (b) The liver 

62. Write a short note on structure and feeding in amoeba. 

63. What do you understand by alimentary canal or digestive tract? 

64. Explain the nutrition in Amoeba with the help of a diagram? 

65. Explain about the different kinds of teeth and their function in human beings?

66. Write the functions of the following organs in the digestive system: mouth, stomach, liver,  small intestine, pancreas 

67. Explain the process of digestion in ruminants and the role of a four chambered stomach?

68. How does Amoeba take in (ingest) the food? From which part of the body undigested food  is egested in Amoeba? 

69. Name the various kind of teeth in our mouth. State their functions. 

70. What is meant by tooth decay? Name some of the foods which are the major cause of tooth  decay. What are the various ways of preventing tooth decay?

71. Describe with the help of labelled diagrams, how feeding and digestion in Amoeba takes  place. 

72. (a) What are ruminants? Which of the following are ruminants? 

Fish, Amoeba, Cow, Humans, Dogs, Sheep, Buffalo, Deer, Goat, Giraffe 

(b) Name the type of carbohydrate that can be digested by ruminants but not by humans.  Give the reason also. 

73. Name the three things secreted by the inner lining of our stomach. Also state their functions.  What is the function of large intestine? 

74. What are incisors, canines, premolars and molars? State their functions.

75. (a) What is meant by the term “rumination”? Name any two ruminants.

(b) Explain why, a cow can digest grass but we cannot.