J. Give reasons for the following.
1. The digested food is absorbed mainly in small intestine.
2. Small intestine is as long as 3.5 metres.
3. Digestion is essential.
4. Stomach wall is thick and muscular.
Answers
Answer:
A) The small intestine is the most important part of the digestive system. Maximum absorption occurs in the small intestine because of the following reasons;
(a) Digestion is completed in the small intestine.
(b) The inner lining of the small intestine is provided with villi which increase the surface area for absorption of digested food.
(c) Wall of the intestine is richly supplied with blood vessels which assimilate the absorbed food to the other parts of the body.
B) As food moves slowly along the great length of the intestine, it has plenty of time to break down properly. The size of the small intestine also maximizes the area of inner lining that food passes and the absorbtion of nutrients. Aakash EduTech Pvt. Ltd.
*C) Digestion is important because your body needs nutrients from food and drink to work properly and stay healthy. ... Your digestive system breaks nutrients into parts small enough for your body to absorb and use for energy, growth, and cell repair
D) These muscles allow the stomach to squeeze and churn the food during mechanical digestion. Powerful hydrochloric acid in the stomach helps break down the bolus into a liquid called chyme. A thick mucus layer that lines the stomach walls prevents the stomach from digesting itself