Food from the small intestine empties into the large intestine, or colon. No digestion and only a small percentage of absorption take place in the large intestine. The large intestine primarily functions to concentrate waste material into a form called feces. Movements of the large intestine compact feces and move it into the rectum, where it is exited from the body through either the anus. Feces is expelled from the body through the voluntary movements of muscles surrounding the rectum.
Rectum: Muscular storage chamber where the undigested food (feces) is held and molded before being pushed through anus during expulsion.
Anus: The exit of alimentary canal, it is closed by a ring of muscle (the anal sphincter). The ring is relaxed during expulsion of feces.
What are the functions of the large intestine?
By absorbing water and mineral ions, the colon compacts undigested residues and other wastes as feces, which are siored briefly in the rectum before expulsion.