from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The innermost of the three primary germ layers of an animal embryo, developing into the gastrointestinal tract, the lungs, and associated structures. Also called hypoblast.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. One of the three tissue layers in the embryo of a metazoan animal. Through development, it will produce the digestive system of the adult.
from the GNU version of the Collaborative International Dictionary of English
- n. The inner layer of the skin or integument of an animal.
- n. The innermost layer of the blastoderm and the structures derived from it; the hypoblast; the entoblast. See Illust. of ectoderm.
from The Century Dictionary and Cyclopedia
- n. In zoology, the completed inner layer of cells in all metazoan animals, formed by the cells of the hypoblast or endoblast, and representing, under whatever modification, the lining of the enteron: opposed to ectoderm.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. the inner germ layer that develops into the lining of the digestive and respiratory systems
This stage of differentiation consists in the formation of either a pouch or an additional layer between the ectoderm and the endoderm, which is called the mesoderm.
The endoderm is the innermost layer that lines the digestive tract.
It proceeded through a primitive embryonic endoderm, which clumped into embryoid bodies.
For example, the outer skin and nervous system come from the ectoderm; the guts and other internal organs come from the endoderm; and the mesoderm furnishes muscle and bone.
The outer layer of this ‘gastrula’ is called the ectoderm, the inner layer is the endoderm, and there are also some cells thrown into the space between the ectoderm and endoderm, which are called mesoderm.
Further tests confirmed that they were, in fact, stem cells capable of differentiating into the cell types that make up the three layers in an embryo – endoderm, mesoderm and ectoderm – a quality that all embryonic stem cells have.
Instead, the standard method for ascertaining whether putative hESCs are truly pluripotent is to inject them into postnatal, immune-deficient mice, and see whether they give rise to teratomas (tumors that consist of disorganized tissue growth of the three embryonic germ layers, endoderm, mesoderm, and ectoderm).
Ectoderm is supposed to be blue or green, mesoderm red, and endoderm yellow!
The third cell engenders formation of the endoderm, including all the vital organs and glands.
Entoderm: the innermost germ layer of the embryo, from which are derived the epithelium of the alimentary canal and accessory structures: = endoderm and hypoblast.