Q.1. Fill in the blanks:
(i) The main steps of digestion in humans are _________ and ___________.
(ii) The largest gland in the human body is _________.
(iii) The stomach releases hydrochloric acid and ______ juices which act on food.
(iv) The inner wall of the small intestine has many finger-like outgrowths called _________.
(v) Amoeba digests its food in the ____________.
Ans. (i) buccal cavity, oesophagus, stomach, small intestine and large intestine.
Buccal cavity(ii) liver
(iii) digestive juices
(v) food vacuole
Q.2. Mark ‘T’ if the statement is true and ‘F’ if it is false:
(i) Digestion of starch starts in the stomach.
(ii) The tongue helps in mixing food with saliva.
(iii) The gallbladder temporarily stores bile.
(iv) The ruminants bring back swallowed grass into their mouth and chew it for some time.
Ans. (i) F
Q.3. Choose the correct option:
(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 in the (i) stomach/(ii) food pipe/(iii) small intestine/(iv) large intestine.
Ans. (a) (iii)
Q.4. Match the items in column I with those in column II:
Q.5. What are villi? What are their location and function?
Q.6. Where is the bile produced? Which component of the food does it digest?
Ans. Bile is produced in the liver and is stored in a sac called the gall bladder. Bile plays an important role in the digestion of fats.Liver with Gall Bladder
Ans. Cellulose is a carbohydrate that can be digested by ruminants. Ruminants have a 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 human beings.
Q.8. Why do we get instant energy from glucose?
Ans. Because glucose easily breakdown in the cell with the help of oxygen and give carbon dioxide, water and energy.
Q.9. Which part of the digestive canal is involved in:
(i) Absorption of food __________.
(ii) Chewing of food __________.
(iii) Killing of bacteria _________.
(iv) Killing of bacteria _________.
(v) Formation of faeces ____________.
(i) Small intestine
(iv) Small intestine
(v) Large intestineLarge Intestine
Q.10. Write one similarity and one difference between the nutrition in amoeba and human beings.
Q.11. Match the items of column I with suitable items of column II:
Q.12. Can we survive only on raw, leafy vegetables/grass? Discuss.