AP BIOLOGY

Detailed explanation-1: -Each villus has a network of capillaries and fine lymphatic vessels called lacteals close to its surface. The epithelial cells of the villi transport nutrients from the lumen of the intestine into these capillaries ( amino acids and carbohydrates) and lacteals (lipids).

Detailed explanation-2: -Villi contain capillary beds, as well as lymphatic vessels called lacteals. Fatty acids absorbed from broken-down chyme pass into the lacteals. Other absorbed nutrients enter the bloodstream through the capillary beds and are taken directly to the liver, via the hepatic vein, for processing.

Detailed explanation-3: -The muscles of the small intestine mix food with digestive juices from the pancreas, liver, and intestine and push the mixture forward to help with further digestion. The walls of the small intestine absorb the digested nutrients into the bloodstream. The blood delivers the nutrients to the rest of the body.

Detailed explanation-4: -The blood vessels are thought to transport proteins and carbohydrates absorbed by the cells of the villi, while the lymphatic capillary removes droplets of emulsified fat (chyle).

Detailed explanation-5: -One of the main functions of villi is to absorb nutrients from the lumen in the small intestine. Since the walls of the villi are only one cell thick, the nutrients are able to quickly pass from the villi into the blood. They do this using a process called diffusion.