The jejunum is located centrally in the abdomen, whereas the ileum lies mostly in the hypogastric region and pelvic cavity.
The jejunum makes up two-fifths of the total length of the small intestine and is about 0.9m in length. It starts at the duodenojejunal flexure and ends at the ileum.
The main function of the jejunum is absorption of important nutrients such as sugars, fatty acids, and amino acids.
It plays an important role for digestion as 40% of the whole small intestine is jejunum. Its functions include absorbing water and nutrients.
Absorption occurs at and is facilitated by numerous one to two cell layer thick fingerlike projection on the surface mucosa (villi) via active passive transport mechanisms. Absorption lipid breakdown product occurs mostly by passive diffusion protein-mediated processes.
Jejunum: Middle of the three parts of the small intestine
