Noun
That stage in the development of the ovum in which the outer cells of the morula become more defined and form the blastoderm.
Source: Webster's dictionaryThe sixth cleavage occurs in a similar order and completes a 64 cell stage, finally the seventh cleavage marks the end of the cleavage stage with a blastula with 128 blastomeres. Source: Internet
During gastrulation the cells of the blastula undergo coordinated processes of cell division, invasion, and/or migration to form two ( diploblastic ) or three ( triploblastic ) tissue layers. Source: Internet
The first three to four months are spent with the blastula in suspended development before it implants itself in the uterus. Source: Internet
The parts that are autotomised or the buds may develop directly into fully formed larvae or may develop through a gastrula or even a blastula stage. Source: Internet