Colon (anatomy)

Colon

The colon is a part of the large intestine. It is between the cecum and the rectum. The colon takes water from the feces that goes through it. The colon in mammals can be divided into four sections:

Ascending colon

This part of the colon goes from the cecum (where the small intestine ends) up the right hand side of the abdomen.^[1]

Transverse colon

This part of the colon goes across the from the ascending colon. It goes underneath the stomach and the pancreas and joins the descending colon near the spleen.^[1]

Descending colon

This part of the intestine is about 30 cm in length.^[2] It travels down the left side of the abdomen.^[1] It is possible to have medical problems with the descending colon including ulcers, cancer and Crohn's disease.^[3]

Sigmoid colon

This is the small "S" shaped part of the colon, about 40 cm in length, which goes from the bottom of the descending colon into the centre of the pelvis to the rectum.^[1] It gets its name from the Greek letter "s", sigma.^[4]

Colon (anatomy) Media

Illustration of the large intestine.
Inner diameters of colon sections
3D File generated from computed tomography of large intestine
Colonic crypts (intestinal glands) within four tissue sections. The cells have been stained to show a brown-orange color if the cells produce the mitochondrial protein cytochrome c oxidase subunit I (CCOI), and the nuclei of the cells (located at the outer edges of the cells lining the walls of the crypts) are stained blue-gray with haematoxylin.
Large intestine histology
Colonoscopy image, splenic flexure,normal mucosa. You can see spleen through it : the black part
Micrograph of normal large instestinal crypts.
Anatomy of normal large intestinal crypts
Colon. Deep dissection. Anterior view.