The large intestine begins with the ileocecal sphincter and coils up the right side of the abdomen, across the back and down the left side of the abdomen where it connects to the rectum and ends with the anus. It serves to manufacture certain vitamins, complete absorption and form and expel feces from the body. The large intestine is about 1.5 m (5 ft) long and 6.5 cm (2.5 in) in diameter and is divided in to four primary regions; the cecum (SEE- kum), colon, rectum and anal canal. The cecum is a hidden, dilated pouch, about 6 cm (2.5 in) long, located slightly below the ileocecal valve.

The colon makes up most of the large intestine and is itself divided into four regions - the ascending, transverse, descending and sigmoid portions. The ascending colon is the part moving up the right side of the body. It is connected to the transverse colon, the part of the large intestine that travels from the right to the left side of you body. The curve formed between the ascending and transverse regions of the colon is called the right colic (hepatic) flexure. The transverse colon connects on the left side of the body to the descending colon, where it forms another curve called the left colic (splenic) flexure. The sigmoid colon is located low in the abdomen. It connects to the descending colon at the left side of the body and streches to the middle of the body where it meets the rectum.

The rectum composes the last 20 cm (8 in) of the large intestine. It is located just in front of the sacrum and coccyx bones. The last 2 to 3 cm (~1 in) of the rectum is called the anal canal. The opening of the anal canal to the exterior of the body is known as the anus. The internal and external anal sphincters guard this opening.