the empty space inside a blastula (= the early stage of development of an animal, consisting of a layer of cells around a hollow space), formed when an egg divides into smaller cells

Under low calcium conditions, large proteins can enter the blastocoel of living embryos. 在低钙条件下，大分子蛋白质可进入活胚胎的囊胚腔。

All embryos that had formed a blastocoel cavity were evaluated.