Endoderm

Definition

The endoderm is one of the three primary germ layers in the early embryo that gives rise to the lining of the digestive and respiratory systems, among other internal structures. It forms during the process of gastrulation and differentiates to become various organ linings and glandular tissues.

Related terms

Ectoderm:

The outermost germ layer that develops into skin, brain, and nervous system tissues.

Mesoderm:

The middle germ layer that gives rise to muscles, bones, blood vessels, and some internal organs like the heart and kidneys.

Gastrulation:

A phase early in embryonic development where cells differentiate into three primary germ layers (ectoderm, mesoderm, endoderm) setting the stage for organ formation