Epiblast
Section through the embryo. (Epiblast visible but not labeled.)
Cell differentiation
Carnegie stage	3
Days	8
Precursor	inner cell mass
Gives rise to	ectoderm, mesoderm, endoderm

In embryology, the epiblast is a tissue type derived from the inner cell mass. It lies above the hypoblast.

In mammalian embryogenesis, the columnar cells of the epiblast are adjacent to the trophoblast, while the cuboidal cells of the hypoblast are closer to the Blastocoele. The epiblast, whilst referred to as the primary ectoderm, differentiates to form all three layers of the trilaminar embryonic disc in a process called gastrulation.

[edit] See also

• Embryogenesis
• Mammalian embryogenesis

[edit] External links

• http://www.iscr.ed.ac.uk/images/tilo_kunath/Tilo-Web-figure-1.gif
• http://www.embryology.ch/allemand/iperiodembry/carnegie02.html
• http://www.med.umich.edu/lrc/coursepages/M1/embryology/embryo/04secondweek.htm
• http://isc.temple.edu/marino/embryology/EMBII97/sld005.htm

This developmental biology article is a stub. You can help Wikipedia by expanding it. v • d • e

v • d • e Developmental biology > Human embryogenesis (development of embryo) and development of fetus First three weeks Week 1 Fertilization · Egg activation · Zygote · Cleavage · Morula · Blastula (Blastomere) · Blastocyst · Inner cell mass Week 2 (Bilaminar) Hypoblast · Epiblast Week 3 (Trilaminar) Germ layers Archenteron/Primitive streak (Primitive pit, Primitive knot/Blastopore, Primitive groove) · Gastrula/Gastrulation · Regional specification Ectoderm Surface ectoderm · Neuroectoderm · Somatopleure · Neurulation · Neural crest Endoderm Splanchnopleure Mesoderm Chorda- · Paraxial (Somite/Somitomere/Sclerotome/Myotome/Dermatome) · Intermediate · Lateral plate (Intraembryonic coelom, Splanchnopleure/Somatopleure) Extraembryonic/ uterus Trophoblast (Cytotrophoblast, Syncytiotrophoblast) Blastocoele · Yolk sack/exocoelomic cavity · Heuser's membrane · Extraembryonic coelom · Vitelline duct Umbilical cord (Umbilical artery, Umbilical vein, Wharton's jelly) · Allantois Placenta · Decidua (Decidual cells) · Chorionic villi/Intervillous space · Gestational sac (Amnion/Amniotic sac/Amniotic cavity, Chorion) Histogenesis Programmed cell death (Apoptosis) · Stem cells · Germ line development Organogenesis Limb development: Limb bud · Apical ectodermal ridge/AER other structures: Eye development · Cutaneous structure development · Heart development · Development of the urinary and reproductive organs (Some dates are approximate—see Carnegie stages and a timeline.)