Colon (anatomy)

In anatomy of the digestive system, the colon is the part of the intestine from the cecum to the rectum. Its primary purpose is to extract water from feces. In mammals, it consists of the ascending colon on the right side, the transverse colon, the descending colon on the left side, the sigmoid colon, and the rectum.

Image:stomach colon rectum diagram.gif

Diseases of the colon

• angiodysplasia of the colon
• colon cancer
• Crohns disease
• diarrhea
• diverticulitis
• Hirschsprung's disease (aganglionosis)
• infective colitis
• polyposis
• pseudomembranous enterocolitis
• ulcerative colitis and toxic megacolon

Role in digesion

The large intestine comes after the small intestine in the digestive track. Although there are differences in the large intestine between different organisms, the large intestine is mainly responsible for storing waste and reclaiming water and maintaining water balance.

By the time the chyme has reached this tube, almost all nutrients have been absorbed by the body and only water and some electrolytes like sodium and chloride are left. As the chyme moves though the large intestine water is removed, while the chyme is mixed with mucus and bacteria, and becomes feces. It is important to know that the large intestine produces no digestive enzymes and that the chemical digestion is completed in the small intestine before the chyme reaches the large intestine.