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morula vs. blastula

[mawr-oo-luh, -yoo-] / ˈmɔr ʊ lə, -yʊ- /

noun

Embryology.

plural

morulas, morulae
  1. the mass of cells resulting from the cleavage of the ovum before the formation of a blastula.

[blas-chuh-luh] / ˈblæs tʃə lə /

noun

Embryology.

plural

blastulas, blastulae
  1. the early developmental stage of an animal, following the morula stage and consisting of a single, spherical layer of cells enclosing a hollow, central cavity.