from the duodenum, chyme passes to the jejunum and ileum. here, tiny villi (finger-like projections) cover the walls of the small intestine. the cells that line the villi are covered with small projections called microvilli. these projections increase the surface area of the small intestine, allowing the chyme to contact more of the small intestine wall. the increased contact causes more efficient food absorption.

during food absorption, food molecules enter the bloodstream through the intestinal walls. capillaries within the villi absorb products of protein and carbohydrate digestion. lymph vessels (lacteals) within the villi absorb products of fat digestion and eventually lead to the bloodstream.

from the small intestine, digested products travel to the liver, one of the body's most versatile organs. hepatocytes (liver cells) detoxify blood of harmful substances such as alcohol and ammonia. And, hepatocytes store fat-soluble vitamins and excess substances such as glucose (sugar) for release when the body requires extra energy.

additional information about intestinal villi:

intestinal villi are tiny, finger-like projections that protrude from the wall of the small intestine and have additional extensions called microvilli which protrude from epithelial cells lining villi. they increase the absorptive area and the surface area of the intestinal wall.

it is important that the food is absorbed at a considerably fast rate so as to allow more food to be absorbed. (If the process is too slow, the concentration of the blood in the blood vessels and the food will be equal, thus, diffusion will not occur.) digested nutrients pass into the villi through diffusion. circulating blood then carries these nutrients away.

information is taken from: