Question

Describe the structure of small intestine and digestion occurs in small intestine.​

Answer 1

.Most of the digestive enzymes in the small intestine are secreted by the pancreas and enter the small intestine via the pancreatic duct. The three major classes of nutrients that undergo digestion are proteins, lipids (fats), and carbohydrates.

Answer 2

The main events occurring in the small intestine are as follows:

a. Bile emulsifies fat present in the food (emulsification means breaking of fat molecules into smaller globules).

b. Pancreatic juice containing trypsin for digesting proteins and pancreatic amylase for starch act upon the food.

c. Bicarbonate ions secreted by duodenal wall make the medium alkaline because it is required for the action of pancreatic enzynies.

d. Enzymes produced in intestinal juice complete the digestive process.

e. Digested food - amino acids, sugar are absorbed by the blood capillaries present in the villi of intestine.

f. Digested fats are absorbed by lymph vessels present in the villi of intestine.