AP BIOLOGY

Detailed explanation-1: -Villi are tiny, finger-like projections from the wall of the small intestine. They line the inner surface of the small intestine. Their role is to increase the surface area within the small intestine. This will lead to the increase of the surface area of absorption as it is the main function of the small intestine.

Detailed explanation-2: -The villi of the small intestine project into the intestinal cavity, greatly increasing the surface area for food absorption and adding digestive secretions.

Detailed explanation-3: -The inside of the small intestine is lined with villi that absorb nutrients from the liquid mixture called chyme produced in the stomach from the food we eat.

Detailed explanation-4: -The epithelial cell are covered by smaller projections like villi known as microvilli which increases the absorption capacity of the intestine. The microvilli is covered with digestive enzymes that help in breaking down carbohydrates and proteins. In this way villi helps in absorption of food.

Detailed explanation-5: -Villi are specialized for absorption in the small intestine as they have a thin wall, one cell thick, which enables a shorter diffusion path. They have a large surface area so there will be more efficient absorption of fatty acids and glycerol into the blood stream.