Primitive streak

primitive streak

An ectodermal ridge in the midline at the caudal end of the embryonic disk from which arises the intraembryonic mesoderm; achieved by inward and then lateral migration of cells; in human embryos, it appears on day 15 and gives a cephalocaudal axis to the developing embryo.

Synonym: germinal streak.

Retrieved from "http://www.biology-online.org/bodict/index.php?title=Primitive_streak&oldid=47699"
First | Previous (Primitive ridge) | Next (Primogeniture) | Last
Please contribute to this project, if you have more information about this term feel free to edit this page.