Passive and Active Absorption of Food: Passive Absorption: It is the absorption of nutrient from the higher concentration to the lower concentration without the expenditure of energy. This process is slow and occurs by simple diffusion, osmosis and facilitated diffusion. During simple diffusion, the nutrients are required to be in higher concentration in the intestine lumen than its cells. The various amino acids and monosaccharides (glucose), some of the electrolytes are absorbed by simple diffusion but it does not result in complete absorption of nutrients. The water and some water-soluble salts are absorbed by osmosis. The absorption of fructose, mannose … Continue reading Passive and Active Absorption of Food