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Cleavage Stage, Ovum MeSH Descriptor Data 2026


MeSH Heading
Cleavage Stage, Ovum
Tree Number(s)
A16.166
Unique ID
D002970
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D002970
Scope Note
The earliest developmental stage of a fertilized ovum (ZYGOTE) during which there are several mitotic divisions within the ZONA PELLUCIDA. Each cleavage or segmentation yields two BLASTOMERES of about half size of the parent cell. This cleavage stage generally covers the period up to 16-cell MORULA.
Entry Term(s)
Segmentation Stage, Ovum
Previous Indexing
Cell Division (1966-1979)
Mitosis (1968-1979)
Ovum (1966-1979)
Zygote (1975-1979)
See Also
Cell Division
Public MeSH Note
80
History Note
80
Date Introduced
1980/01/01
Last Updated
2007/07/09
Cleavage Stage, Ovum Preferred
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