From Wikipedia, the free encyclopedia
Oogenesis is the creation of an ovum (egg cell) in the ovarian follicle of the ovary.
In mammals, oogonial transformation into oocytes (oocytogenesis) is completed either before or shortly after birth. Further development comes to a rest during prometaphase I of meiosis, known as the Dictyate stage, until puberty triggers oogenesis. In Ascaris, the oocyte does not even begin meiosis until the sperm touches it.
Once ovulation begins, the oocytes undergo meiosis and split into four cells, of which only one becomes an ovum; the others become polar bodies. There may be two or three polar bodies. If only two are formed, that is because one is diploid and did not undergo meiosis II.
It is interesting to note that such an important process in animal life cycles is done completely without the aid of spindle-coordinating centrosomes.
[edit] See also
[edit] External links
| Female reproductive system
|
| Ovaries: Germinal epithelium | Tunica albuginea | cortex (Cumulus oophorus, Stroma of ovary) | Medulla of ovary
Follicles: Corpus luteum | Corpus albicans | Granulosa cells | Membrana granulosa | Corona radiata | Theca of follicle | Follicular antrum | Follicular fluid | Zona pellucida | Folliculogenesis/Oogenesis
Ligaments: Proper | Suspensory | Round | Broad (Mesovarium, Mesosalpinx, Mesometrium) | Cardinal
Fallopian tubes: Isthmus | Ampulla | Infundibulum | Fimbria
Uterus: cervix/neck (External orifice, Canal of the cervix, Internal orifice) | corpus/body (Cavity of the body, Fundus) | layers (Endometrium, Myometrium, Perimetrium)
Vulva: Mons pubis | Labium (Labia majora, Labia minora, Cleft of venus, Labial commissures) | Clitoris (Clitoral hood , Clitoral glans, Frenulum clitoridis, Clitoral crura, Corpus cavernosa, Vestibular bulbs) | Bartholin's glands | Vagina (Skene's glands , Fossa of vestibule of vagina) | Frenulum labiorum pudendi | Hymen | Vulval vestibule
Breast: Mammary glands | Nipple | Areola | Lactiferous duct
G-spot | Urethral sponge
|
de:Oogenese
pl:Oogeneza
