Ectoderm

Ectoderm is one of the three primary germ cell layers in the very early embryo. The other two layers are the mesoderm (middle layer) and endoderm (most proximal layer), with the ectoderm as the most exterior (or distal) layer. It emerges first and forms from the outer layer of germ cells.

Generally speaking, the ectoderm differentiates to form the nervous system (spine, peripheral nerves and brain), tooth enamel and the epidermis (the outer part of integument). It also forms the lining of mouth, anus, nostrils, sweat glands, hair and nails.

In vertebrates, the ectoderm has three parts: external ectoderm (also known as surface ectoderm), the neural crest, and neural tube. The latter two are known as neuroectoderm.

Other articles related to "ectoderm":

Histogenesis - Production
... Mesoderm Vertebrate Intermediate mesoderm Mesoderm Vertebrate Lateral plate mesoderm Ectoderm General Nervous system Ectoderm General Outer part of integument ...
Harvestman Anatomy - Digestion
... The foregut (stomodeum) develops from the ectoderm ... Unlike the fore- and hindgut, which are derived from ectoderm, it has no cuticular lining ... The hindgut is a short invagination of the ectoderm, linking the midgut to the anus ...
Surface Ectoderm
... The surface ectoderm (or external ectoderm) forms the following structures Skin (only epidermis dermis is derived from mesoderm) (along with glands, hair ...
Bilaminar Blastocyst - Epiblast Cells During Gastrulation - Ectoderm Development
... do not ingress through the primitive streak rather they remain on the outside and form the ectoderm ... It is not long until the ectoderm becomes the neural plate and surface ectoderm ... an embryo develops cranial to caudal, the formation of ectoderm does not happen at the same rate during development ...