The gastrointestinal system or alimentary canal exists as a tube that runs through the body from mouth to anus. The wall of the tube is composed of four layers of tissue. The outermost layer, the serosa, is part of a large tissue called the peritoneum, which covers internal organs and lines body cavities. Extensions of the peritoneum, called mesenteries, anchor the organs of digestion to the body wall. Fatty, apron-like structures that hang in front of the abdominal organs are also... więcej

Salem Press Encyclopedia of Science, 2023. 3p.