Entoderm

Entoderm is the internal embryonic leaf. A homogeneous layer of cells that forms the lining of the intestinal cavity of the embryo (E. entoderm), and the lining of his yolk SAC. From intestinal endoderm develops epithelium of intestinal tube, as well as digestive glands, including the liver and the pancreas.

Entoderm (from the Greek. entos inside, derma - skin layer) - internal embryonic leaf, the innermost of cell layers of the embryo in all multicellular animals.
Education endoderm and thus the transformation of the germ of a single-layer (blastula) in DL (gastrula) - gastropatia - occurs at different animals in different ways. In higher vertebrates and man is delamination (detachment) endoderm from blastoderm.
The germs of two-layer animals (type coelenterates) entoderm, separate from the ectoderm during gastrulation, directly differentiated in the lining of the intestine, consisting, in addition to the epithelial cells of muscle and nerve cells. Most three-layer animals (superior types), including in lower chordates (tunicates, lunatic), in the process of gastrulation are the primary ectoderm (epiblast) and primary entoderm (hypoblast). From primary endoderm segregated average embryonic leaf - mesoderm (see), and in lower chordates is also a root of the spinal cord, or chord, then the rest of the primary endoderm becomes actual entodermal (secondary). In higher vertebrates, including humans, already in the first phase of gastrulation from blastoderm cleaved net embryo endoderm (secondary), while the material of the future mesoderm and chord remains part of epiblast and is separated from it only in the second phase of gastrulation.
Most animals and humans secondary entoderm is a rudiment of the epithelial lining of the middle intestine and glands (glands of the stomach and intestine, the parenchyma of the liver and the pancreas).
Tissue derived endoderm, by a set of properties and transformations in normal, experimental and pathological conditions are to enterogermina tissue type (the epithelium of intestinal type, N. G. Khlopin). Cm. also Embryonic leaves.