Endoderm

Endoderm
Organs derived from endoderm.
Details
Days	16
Precursor	hypoblast
Identifiers
MeSH	A16.254.425.407
FMA	69071
Anatomical terminology []

Endoderm is one of the three primary germ layers in the very early embryo. The other two layers are the ectoderm (outside layer) and mesoderm (middle layer), with the endoderm being the innermost layer. Cells migrating inward along the archenteron form the inner layer of the gastrula, which develops into the endoderm.

The endoderm consists at first of flattened cells, which subsequently become columnar. It forms the epithelial lining of multiple systems.

In plant biology, endoderm corresponds to the innermost part of the cortex (bark) in young shoots and young roots often consisting of a single cell layer. More the plant will become older, more endoderm will lignify.

The following chart shows the tissues produced by the endoderm. The embryonic endoderm develops into the interior linings of two tubes in the body, the digestive and respiratory tube.

Liver and pancreas cells are believed to derive from a common precursor.

In humans,the endoderm can differentiate into distinguishable organs after 5 weeks of embryonic development.

Section through the embryo.

Section through ovum imbedded in the uterine decidua

Signaling pathway to inducing endoderm

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)