出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2010/12/23 15:13 UTC 版)
Yolk plug is the remaining patch of endodermal cells that is created during the formation of the ventral lip of the blastopore. It is a patch of large endodermal cells which remains exposed on the vegetal surface of the amphibian blastula that will eventually be internalized by epiboly.