meroblastic cleavage

biology

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June 30, 2026

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Meroblastic cleavage is a type of cell division in an embryo where only a portion of the egg's cytoplasm divides. This occurs in eggs with a large amount of yolk, such as those of birds, reptiles, and many fish. The yolk hinders complete division, so cleavage is restricted to a small disc of cytoplasm at the animal pole. The dividing cells, called blastomeres, form the embryo proper, while the uncleaved yolk serves as nourishment. This contrasts with holoblastic cleavage, where the entire egg divides.12

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animal development
Cleavage
…case cleavage is partial, or meroblastic. Only a part of the egg material then is subdivided into cells, the rest remaining as a mass that serves as nourishment for the developing embryo.
Read More
…case cleavage is partial, or meroblastic. Only a part of the egg material then is subdivided into cells, the rest remaining as a mass that serves as nourishment for the developing embryo.
Read More