Question

Which statement accurately describes cleavage?

Options

• The embedding of the blastocyst into the endometrium

• The formation of three primary germ layers

• The transformation of morula into a hollow blastocyst

• A series of rapid mitotic divisions of the zygote without an increase in size

Answer 1

Cleavage is specifically a series of rapid mitotic divisions of the zygote that produces smaller cells called blastomeres. The defining characteristic is that these divisions increase the number of cells without increasing the overall size of the embryo, thereby restoring the normal nucleo-cytoplasmic ratio.