Most grass embryos have a flap-like structure known as the epiblast .
大多数禾本科胚有一片瓣状结构通常称为外胚叶。
Germ potential is established after conception in a totipotent zygote and retained subsequently during development in blastomers of morula , cells form the inner cell mass of blastocyst , epiblast and population of primordial germ cells .
