Cleavage (embryo)

Division of cells in the early embryo

In embryology, cleavage is the division of cells in the early development of the embryo, following fertilization but before amniogenesis. The zygotes of many species undergo rapid cell cycles with no significant overall growth, producing a cluster of cells the same size as the original zygote. The different cells derived from cleavage are called blastomeres and form a compact mass called the morula.

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