oogenesis


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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]
Enlarge picture
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 ?
when females from the 4 sites were moved to the same site before oogenesis, no significant differences were observed in overall or [omega]3/[omega]6 fatty acid composition of oyster eggs by river or age (P > 0.
Oocytes were fully formed when adult females eclosed from the pupa, and oogenesis was continual throughout the lifespan of the female.
The cortisols in eggs are seemingly originated from the maternal derived yolk, where they are accumulated during oogenesis (Tagawa etal.
Translation of maternal mRNA during early oogenesis in a telo trophic-meroistic insect (Dysdercus intermedius).
A slight depression of oogenesis was reported in Drosophila melanogaster when fed a diet containing lufenuron before vitellogenesis development: egg hatching is strongly inhibited (Wilson & Cryan 1997).
Their topics include the evolution and taxonomy of snakes, oogenesis and early embryogenesis, viviparity and placentation, hormones and reproduction in free-ranging snakes, environmental and neuroendocrine control of reproduction in snakes, the sexual segment of the kidney, pheromones in snakes, offspring size variation, paternity patterns, and parental care in snakes.
El periodo de mitosis oogonial, ocurre entre los dias 45 a 110 de gestacion y es el periodo de mayor oogenesis.