| The muscular, hoselike portion of the digestive system extending from the lower end of the stomach to the anal opening. In humans the fairly narrow small intestine is a tubelike structure that winds compactly back and forth within the abdominal cavity.
The contraction of its muscular walls (peristalsis) propels food onward while digestion is completed.
Innumerable minute projections (villi) in the intestinal lining absorb the altered food for distribution by the blood and lymphatic systems to the rest of the body.
In the lower right abdominal cavity, the small intestine joins the large intestine (colon), where most of the water content of the remaining mass is absorbed.
see also: imperforate anus, anus, rectum | 
