Digestive system. Computer artwork showing a healthy human digestive system, superimposed on the outline of a human figure. At top is the bean- shaped stomach, in which swallowed food is stored and digested by acidic gastric juices. The food then enters the small intestine through a C-shaped duodenum. The small intestine is the longest region of the digestive system, seen as the coiled structure (yellow/red) in middle of the abdomen. Here, digested food is absorbed into the blood. Food residue then passes into the large intestine or colon (orange), a wide circular tract in which excess water is absorbed. Faeces is stored in the rectum (tube at lower centre).