Title: Small Intestine: Anatomy, Function, and Treatment
Headings: The Anatomy of the Small Intestine
The Anatomy of the Small Intestine
The largest digestive organ breaks down food and absorbs nutrients
Anatomy
The Mesentery
The Lymph System and the Small Intestine
Location
Anatomical Variations
Function
Absorption of Nutrients
The Lining of the Small Intestine
The Enteric Nervous System
Associated Conditions
Treatment
Tests

Content: In addition, there is some limited absorption of nutrients that takes place in the duodenum, such as the absorption of iron. The jejunum receives the undigested food from the duodenum and absorbs nutrients such as sugar, amino acids, and fatty acids, via finger-like projections called villi. Over 95% of the body’s carbohydrate and protein absorption takes place in the jejunum. 1 ﻿
The ileum receives the food from the jejunum and empties into the large intestine. It continues the process of absorption via the intestinal wall villi, absorbing any products of digestion that were not absorbed by the jejunum. This includes vitamin B12, bile salts, and more. Absorption of Nutrients
Although the small intestine is comprised of a surface area that should be approximately 10.7 square feet, the absorptive surface of the small intestine is nearly 2,690 square feet. How is this possible? There are three key features of the small intestines that enable it to account for its enormous absorptive surface area, including: 2 ﻿
Mucosal folds: