The rectum has little shelves in it called transverse folds. These folds help keep stool in place until you're ready to go to the bathroom. When you're ready, stool enters the lower rectum, moves into the anal canal, and then passes through the anus on its way out.
Diagram of the Rectum
by Donna Myers
for About.comUpdated: September 14, 2006
About.com Health's Disease and Condition content is reviewed by the Medical Review Board
The rectum is about eight inches long and serves, basically, as a warehouse for poop.
Rectum
© Donna Myers 2006
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