Why are villi present in the intestine and not in the stomach ?

Explanation

1. In the stomach there is no absorption of food. Absorption takes place only in the intestine through villi Absorption is a process by which the end product of digestion passes through the intestinal mucosa into the blood and lymph.
2. The villi in the lumen of ileum are the absorbing units consisting of lacteal duct in the middle surrounded by fine network of blood capillaries. The process of absorption involves active, passive and facilitated transport.
3. Small amounts of glucose, amino acids and electrolytes like chloride ions are generally absorbed by simple diffusion. The passage of these substances into the blood depends upon concentration gradeinsts.