Intestine
Intestine, also bowels, in higher animals, the portion of the digestive tract between the stomach and anus. In humans the intestine is divided into two major sections: the small intestine, which is about 6 m (20 ft) long, where the most extensive part of digestion occurs and where most food products are absorbed; and the large intestine, which has a larger diameter and is about 1.5 m (5 ft) long, where water is absorbed and from which solid waste material is excreted (see Digestive System ; Feces ). The small intestine, which is coiled in the center of the abdominal cavity (see Abdomen ), is divided into three sections. The upper portion includes the pylorus, the opening at the lower part of the stomach, through which the contents of the stomach pass into the duodenum. The duodenum is a horseshoe-shaped section surrounding part of the pancreas and the pancreatic duct, as well as ducts from the liver and gall bladder that open into it. The middle part of the small intestine, extending...