Ncert solution class 7 science ch-2 questions 1 to 12.

Ncert solution class 7 science ch-2 questions 1 to 12.

science book
science book

questions 1 to 5.

Q 1.fill in the blank:-

(a)answer=digestion,ingestion,absorption,assimilation and egestion.
(b)answer=liver.
(c)answer=digestive.
(d)answer=villi.
(e)answer=vacuole.

Q 2.mark true or false statements.

Answer:
(a) false
(b) true
(c) true
(d) true

Q 3.tick () mark in correct answer.

Answer:
(a) small intestine
(b) large intestine

Q 4.match the following.

(a) food components------- product (s) of digestion
(b) carbohydrates ----------- sugar
(c) proteins -------------------- amino acid
(d) fats---------------------------- fatty acid and glycerol

Q 5.What are villi? What is their location and function?
Answer:villi is small finger-like estimates from small intestine walls. They increase the surface area for the absorption of digested food. The blood vessels inside the villi can absorb nutrients 

 questions 6 to 11.


Q 6.Where is the bile produced? Which component of the food does it help to digest?
Answer:Bile juice littercretes stored in the bladder of the gall. Bile plays an important role in the digestion of fat.

Q 7.Name the type of carbohydrate that can be digested by ruminants but not by humans. Give the reason also.
Answer:Cellulose is a type of carbohydrate that can be digested by Rominant, not by humans. Rominants have a large pouch-like structure between small and large intestines, where the food containing cellulose is digested with the action of certain bacteria. On the other hand, humans can not digest cellulose because cellulose digestive enzymes are absent in them.

Q 8.Why do we get instant energy from glucose?
Answer:Glucose is a simple sugar. Carbohydrates, when consumed, have to digest in glucose. Since glucose can be easily absorbed in the blood, it provides energy to the body. Therefore, when glucose is taken directly, it does not digest and thus acts as an immediate source of energy.

Q 9.Which part of the digestive canal is involved in:
(i)answer: small intestine
(ii)answer: buccal activity
(iii)answer: stomach
(iv)answer: small intestine 
(v)answer: large intestine 

Q 10.Write one similarity and one difference between the nutrition in Amoeba and human beings.
Answer:Similarity between amoeba and nutrition in humans:
Both amoeba and humans require energy for the development and maintenance of their body. It is taken from energy consuming food. The food they consume are always in complex form and hence the process of digestion is divided into simple forms. Therefore, these two organisms have heterotropes.
Differences between amoeba and nutrition in humans.
Humans:-human have  a mouth complex digestion system.
Amoeba:-
mouth and digestive system absent in amoeba.

Q 11. Match the following column:-
Answer :
          Column I                   column II
(i) salivary gland-------- saliva secretion
(ii) stomach---------------- acid release
(iii) liver--------------------- bile juice secretion
(iv) rectum----------------- storage undigested food
(v) small intestine------- digested is completed
(vi) large intestine ----- absorption of water


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