Embryologically, the liver develops from the foregut and mesenchyme, which develop from the endoderm, one of the germ layers. In the human embryo, the hepatic diverticulum is an enlarged endodermal tube of the foregut into the mesenchyme, which branches and forms the basis of the liver. The liver plays an important role in metabolism. It has functions in many other areas in the body, including glycogen storage, production of red blood cells, plasma and protein synthesis, hormone production and detoxification. The liver also produces bile and bile acids, an alkaline fluid that helps digest fat, and sends this secretion to the gallbladder and duodenum through the hepatic ducts. Therefore, this organ is considered a part of the biliary system.
