
epiblast
Sign in to saveAlso known as primitive mesoderm
In amniote embryonic development, the epiblast (also known as the primitive ectoderm) is one of two distinct cell layers arising from the inner cell mass in the mammalian blastocyst, or from the blastula in reptiles and birds. It drives the embryo proper through its differentiation into the three primary germ layers, ectoderm, mesoderm and endoderm, during gastrulation. The amniotic ectoderm and extraembryonic mesoderm also originate from the epiblast.
Key facts
- Embryology.Name
- Epiblast
- Embryology.Latin
- epiblastus
- Embryology.Image
- Human Embryo Day9.png
- Embryology.Caption
- Human embryo at day 9. Epiblast (pink) is on top of the hypoblast (brown)
- Embryology.CarnegieStage
- 3
- Embryology.Days
- 8
- Embryology.Precursor
- Inner cell mass
- Embryology.GivesRiseTo
- Ectoderm, mesoderm, endoderm
via Wikipedia infobox
~6 min read
Encyclopedic overview
7 sectionsContents
- Discovery of the epiblast
- Mammals
- Epiblast diversity
- Birds
- Reptiles
- See also
- References
In amniote embryonic development, the epiblast (also known as the primitive ectoderm) is one of two distinct cell layers arising from the inner cell mass in the mammalian blastocyst, or from the blastula in reptiles and birds. It drives the embryo proper through its differentiation into the three primary germ layers, ectoderm, mesoderm and endoderm, during gastrulation. The amniotic ectoderm and extraembryonic mesoderm also originate from the epiblast.
The other layer of the inner cell mass, the hypoblast, gives rise to the yolk sac. The layer surrounding the inner cell mass, the trophectoderm, gives rise to the chorion.
Excerpted from Wikipedia’s “epiblast” article, available under the CC BY-SA 4.0 licence.