digestion in the 3 parts of the small intestine....

[xcandykissesx33]

hey! ok so here's my question! i know that in the small intestion the chemical digestion of chyme takes place but my teacher wants to know like what happens in all 3 sections of the small intestine?! anyone know?! thanks soooo much for your help

[Navin]

The 3 sections appear in this order: duodenum, jejunum and ileum.

Duodenum:
Stomach empties its contents into here. Bile duct excretes bile (to increase surface area of fat) here. Pancreas secrete pancreatic juice via the pancreatic duct here. Pancreatic juice contains these enzymes: lipase for fat digestion, amylase for starch digestion and trypsinogen (becomes trypsin) for protein digestion. It also contain sodium bicarbonate to make an alkaline pH environment.

Duodenum/Jejunum/Ileum:
Intestinal juice is secreted by all three parts. It contains these enzymes: Erepsin for peptone digestion, lipase for fat digestion, maltase to digest maltose, sucrase to digest sucrose and lactase to digest lactose.

Ileum:
The walls of the ileum contain villi which absorb the end-products of digestion.