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The second part is called the transverse colon and goes horizontally across the abdomen from the right side to the left side.
At the end of the horizontal section, the colon moves down on the left side of the abdomen and this part is called the descending colon.
The fourth part is known as the sigmoid colon and is the last part of colon. This part is called sigmoid because of it is shaped like a S. The sigmoid colon joins the rectum, and the rectum continues to the anus.
The rectum and anal canal
The rectum is the last part of large intestine and is located at the end of the colon. Rectum is about 5 inches in length and is normally empty, except just prior to having a bowel movement. Stool is pushed in to the rectum by the colon and is in turn excreted through the anal canal. The anal canal has two muscular "valves", called the internal and external sphincters and these control the movement of stool. The sphincters allow us to have control over bowel movement and retain stool until we are ready to evacuate the rectum