The<unk> , also known as the<unk>  bowel, is the last part of the gastrointestinal tract and of the digestive system in vertebrates. Water is absorbed here and the remaining waste material is stored in the rectum as feces before being removed by defecation. The colon is the longest portion of the<unk> , and the terms are often used interchangeably but most sources define the<unk>  as the combination of the cecum, colon, rectum, and anal canal. Some other sources exclude the anal canal. In humans, the<unk>  begins in the right iliac region of the pelvis, just at or below the waist, where it is joined to the end of the small<unk>  at the cecum, via the ileocecal valve. It then continues as the colon ascending the abdomen, across the width of the abdominal cavity as the transverse colon, and then descending to the rectum and its endpoint at the anal canal. Overall, in humans, the<unk>  is about long, which is about one-fifth of the whole length of the human gastrointestinal tract.
Large intestine
Small intestine
Stomach
Gastrointestinal tract
Liver
Gastric mucosa
Lung
Kidney