discoblastula /dis′kōblas″tyələ/ [Gk, diskos, flat plate, blastos, germ] , a blastula formed from the partial cleavage that occurs in a fertilized ovum containing a large amount of yolk. It develops from the blastodisc and consists of a cellular cap, or blastoderm, separated from the uncleaved yolk mass by a small cavity, the blastocele.
