oogenesis

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Related to Oocyte maturation: oogenesis, primary follicle

oogenesis

 [o″o-jen´ĕ-sis]
the development of mature ova from oogonia. adj., adj oogenet´ic.

o·o·gen·e·sis

(ō'ō-jen'ĕ-sis),
Process of formation and development of the oocyte.
Synonym(s): ovigenesis, ovogenesis
[G. ōon, egg, + genesis, origin]

oogenesis

/oo·gen·e·sis/ (o″o-jen´ĕ-sis) the process of formation of female gametes (oocytes).oogenet´ic
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Oogenesis, depicting only six of the 46 double-stranded chromosomes (oogonium, primary oocyte), three of the 23 double-stranded chromosomes (secondary oocyte, first polar body), and three of the 23 single-stranded chromosomes (second polar body, spermatozoon, and female and male pronuclei) in human oogenesis, and showing random assortment of homologous chromosome pairs. Crossing over, which may occur in meiosis I, has been omitted. Progression through meiosis II is only completed if fertilization occurs; the spermatozoon and male pronucleus are depicted out of scale for clarity.

oogenesis

(ō′ə-jĕn′ĭ-sĭs)
n.
The formation, development, and maturation of an ovum.

o′o·ge·net′ic (-jə-nĕt′ĭk) adj.

oogenesis

[ō′əjen′əsis]
Etymology: Gk, oon + genesis, origin
the formation of the female gametes, or ova. The female infant is born with the entire number of primary oocytes that will function throughout reproductive life. Only a fraction of these survive until puberty, and only a small percentage will be ovulated. Follicles containing the primary oocytes are found in varying stages of development in the ovary of the sexually mature woman. Egg and sperm formation differ considerably in the number and size of gametes resulting from gametogenesis, the total number of gametes produced in a lifetime, and the time sequence for the initiation of the meiotic divisions and the completion of the cycle. Also called ovogenesis. Compare spermatogenesis. See also gametogenesis, meiosis, menstrual cycle, ovulation. oogenetic, adj.
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Oogenesis

oogenesis

Embryology The process of ♀ gamete formation

o·o·gen·e·sis

(ō'ŏ-jen'ĕ-sis)
Process of formation and development of the oocyte.
Synonym(s): ovigenesis.
[G. ōon, egg, + genesis, origin]
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OOGENESIS

oogenesis

(o?o-jen'e-sis) [? + genesis, generation, birth]
The developmental process by which the mature human ovum (the female reproductive cell) is formed. Formation begins during the first 3 months of female embryonic life with the development of ovarian follicles. Each follicle contains one oogonium which, through the process of mitosis, becomes a primary oocyte containing 46 chromosomes. The oocyte then undergoes the first meiotic reduction division, resulting in formation of a secondary oocyte and a polar body, each containing 22 autosomes (half the number of chromosomes that are found in nongerm cells) and one X heterosome. Further division is arrested in prophase until the female reaches puberty. The second meiotic division begins at ovulation and reaches metaphase where, once again, division is arrested until the ovum is fertilized. The second meiotic division is completed at fertilization, ending with formation of the mature haploid ovum and one polar body. Synonym: ovigenesis
See: illustration; meiosisoogenetic (-je-net'ik), adjective

oogenesis

The production of egg cells (ova) in the ovaries and their preparation for release and fertilization. Oogenesis starts in the fetal ovary with the formation of OOGONIA. These divide by MEIOSIS to form OOCYTES.

oogenesis

or

ovogenesis

the process of GAMETE production in female DIPLOID (2) animals. see GAMETO GENESIS.

oogenesis

the development of mature ova from oogonia. See also avian oogenesis.
References in periodicals archive ?
Effect of growth hormone (GH) on in vitro nuclear and cytoplasmic oocyte maturation, cumulus expansion, hyaluronan synthases, and connexins 32 and 43 expression, and GH receptor messenger RNA expression in equine and porcine species.
The antioxidant, melatonin, is involved in reproductive processes including follicular development, oocyte maturation and ovulation (11).
To obtain serum free IVM medium, bovine serum albumin (BSA) is an alternate source for oocyte maturation (Wydooghe et al.
This may be an important mechanism for the regulation of the final stages of follicle and oocyte maturation.
Because errors during oocyte maturation lead to pregnancy loss, birth defects and infertility, this work will not only provide important insights into fundamental cellular mechanisms, but will also have important implications for human health.
Effect of angiotensin II with follicle cells and insulin-like growth factor-I or insulin on bovine oocyte maturation and embryo development.
Intracellular calcium release mechanisms are accurately modulated during oocyte maturation and maximal sensitivity of calcium release is acquired during final stage of oocyte maturation.
In addition, some events during bovine oocyte maturation including mitogenesis and metabolism are regulated by cytosolic kinase activity such as MAPK also called "extracellular signal-regulated kinase" (ERK) and maturation promoting factor (MPF).
For example, elevation of cAMP or cGMP generally blocks oocyte maturation in mammals but promotes maturation in nemerteans.