Question

We eat food composed of all the nutrients like carbohydrates, proteins, fats, vitamins, minerals, and water. After digestion, these are absorbed in the form of glucose, aminoacids, fatty acids, glycerol etc. What mechanisms are involved in absorption of digested food and water?

Answer 1

Absorption is the process by which nutrients pass from the alimentary canal (mainly the small intestine) into the blood and lymph. The mechanisms involved in the absorption of digested food (nutrients other than water) are simple diffusion, facilitated diffusion, and active transport. Glucose is absorbed by active transport, some amino acids are absorbed by active transport, and some by facilitated diffusion, fatty acids and glycerol are absorbed by simple diffusion. Mechanism /involved in the absorption of water is osmosis.