Necessary Life Functions of the Small Intestine
- Digestion: the small intestine aids in digestion by receiving chyme and breaking down its nutrients. Structures in the small intestine (microvilli, villi, and lacteal) help absorb nutrients. The remaining “foodstuffs” is broken down and sent to the large intestine as a waste product. The mucosa cells absorb the nutrients and delivery it to the capillaries.
- Metabolism: for the small intestine, chemical digestion begins in the duodenum. The duodenum has a tight sphincter that separates the small intestine from the stomach. This sphincter allows for only a small amount of chyme to enter the small intestine. After being passed through the duodenum, the chyme enters the jejunum. From the jejunum, chyme continues on to the ileum. The ileum joins the large intestine to the small intestine with its ileocecal valve. Enzymes produced by the intestinal cells and the pancreas complete the chemical break down of foods in the small intestine.
- Excretion: the pancreas and the liver both excrete enzymes into the small intestine to help aid in the chemical digestion in the small intestine. With the help of these excretions, the small intestine is able to break down food, nutrients, and waste products and distribute them properly.