How is food absorbed into the body by the villi in the small intestine?
Intestinal villi are small finger like projections that extend into the lumen of the small intestines. Each villus has many microcilli projecting from its epithelium.
The villi and microvilli increase intestinal absorptive surface providing exceptionally efficient absorbtion of nutrients in the lumen.
Certain digestive enzymes are present on their surface which aid in digestion.
Villi are specialised for absorption and have very thin walls ( single cell thick ) . This enables a shorter diffusion path. They have a rich blood supply to keep a concentration gradient.
Villus capillaries collect amino acids and simple sugars and absorb them into the blood stream.
Lymph capillaries in the villi collect absorbed triglycerides, cholesterol and amphipathic proteins and transport it to the rest of the lymph fluid.