Germinal vesicle

Oocyte
Identifiers
MeSH	A05.360.490.690.680
Anatomical terminology []

An oocyte (UK: /ˈoʊəsʌɪt/, US: /ˈoʊ.oʊ.saɪt/), oöcyte, ovocyte, or rarely ocyte, is a female or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation. Cryoconservation of animal genetic resources have been put into action as a means of conserving traditional livestock.

The formation of an oocyte is called oocytogenesis, which is a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, and of secondary oocytes after it as part of ovulation.

Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development.

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