ectoderm
Noun
Meaning
The outer layer of the blastoderm; epiblast.
The external skin or outer layer of an animal or plant, this being formed in an animal from the epiblast. See Illust. of Blastoderm.
Source: Webster's dictionarySynonyms
Hypernyms
Hyponyms
Phrases with the word
Examples
Because of these different morphogenetic properties, the cells of each germ layer move to form sheets such that the ectoderm ends up on the outside, mesoderm in the middle, and endoderm on the inside.
ES cells are pluripotent and give rise during development to all derivatives of the three primary germ layers : ectoderm, endoderm and mesoderm.
However, all molluscan shells are formed from the ectoderm (outer layer of the embryo); in cuttlefish (Sepia spp.
In Sepia, which has an internal shell, the ectoderm forms an invagination whose pore is sealed off before this organic framework is deposited.
Longitudinal muscular fibrils formed from the cells of the ectoderm allow tentacles to contract when conveying the food to the mouth.
The ectoderm begins to grow rapidly as a result of chemicals being produced by the mesoderm.