Endoderm (from the Greek words "endon" - inside and "dermis" - skin) is one of the three germ layers formed during the process of gastrulation. The endoderm lines the inner wall of the primary intestine, and also gives rise to the digestive tract and its outgrowths - the liver, lungs and pancreas.
During gastrulation, the embryo is divided into three main layers - endoderm, mesoderm and ectoderm. The endoderm is formed from the inside of the embryo and lines the inner wall of the primary intestine, which will later become the digestive tract. The endoderm also gives rise to various organs and tissues that are associated with digestion and metabolism.
The liver is one of the most important organs developing from the endoderm. It performs many functions, including processing and storing food, producing bile, and disposing of toxins. The lungs are also formed from the endoderm and serve for gas exchange - the entry of oxygen into the blood and the removal of carbon dioxide. The pancreas is also formed from the endoderm and is responsible for producing insulin and other hormones necessary for processing food.
The endoderm is an important germ layer that ensures the development of the organs of the digestive and respiratory systems in the embryo. Thanks to its development, humans and other mammals have developed a complex system that ensures the vital functions of the body.