The bowel is divided into the small intestine and the large intestine (colon, rectum and anus). The main function of the small intestine is to absorb nutrients released from the food digested in the stomach. The large intestine absorbs water from food and forms semi-solid and solid food waste into stools, which are eliminated from the body through the anus. Waste product is moved along the digestive system by a wave of involuntary contractions (peristalsis).