oocyte


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oocyte

 [o´o-sīt]
an immature ovum; it is derived from an oogonium, and is called a primary oocyte prior to completion of the first maturation division, and a secondary oocyte between the first and second maturation division.

o·o·cyte

(ō'ō-sīt),
Female gamete or sex cell. When fertilized by a sperm, an oocyte is capable of developing into a new individual of the same species; during matuation, the oocyte, like the sperm, undergoes a halving of its chromosomal complement so that, at its union with the male gamete, the species number of chromosome (46 in humans) is maintained; yolk contained in the oocytes of different animal species varies greatly in amount and distribution, which influences the pattern of the cleavage divisions.
See also: egg, ovum.
Synonym(s): ovocyte
[G. ōon, egg, + kytos, a hollow (cell)]

oocyte

/oo·cyte/ (-sīt) the immature female reproductive cell prior to fertilization; derived from an oogonium. It is a primary o. prior to completion of the first maturation division, and a secondary o. in the period between the first and second maturation divisions .

oocyte

(ō′ə-sīt′)
n.
A diploid cell from which an egg or ovum develops by meiosis. A primary oocyte divides to produce a polar body and a secondary oocyte, which divides again to produce the ovum and another polar body.

oocyte

[ō′əsīt]
Etymology: Gk, oon + kytos, cell
a primordial or incompletely developed ovum.

oocyte

Egg Histology The female reproductive or germ cell. Cf Sperm.

o·o·cyte

(ō'ŏ-sīt)
The female sex cell. When fertilized by a sperm, a gamete or zygote is capable of developing into a new individual of the same species; during maturation, the oocyte, like the sperm, undergoes a halving of its chromosomal complement so that, at its union with the male gamete, the species number of chromosomes (46 in humans) is maintained; yolk contained in the oocyte (ova in nonhuman species) varies greatly in amount and distribution, which influences the pattern of the cleavage divisions. In nonhuman females, the term is ovum.
[G. ōon, egg, + kytos, a hollow (cell)]

oocyte

A cell in the OVARY that undergoes MEIOSIS to produce an OVUM. In meiosis the 46 chromosomes are reduced to half the normal number (HAPLOID), so that the full complement can be restored by a haploid contribution from the sperm. Primary oocytes develop in the ovaries of the fetus but only a fraction of these will ever give rise to OVULATION. Secondary oocytes divide to form the mature OVUM but the second maturation division occurs only after the ovum has been fertilized by a sperm.

oocyte

an early stage in GAMETO GENESIS of female animals, ‘primary’ oocytes being DIPLOID (1) and ‘secondary’ oocytes HAPLOID (1) having undergone the first meiotic division. Human females are born with the primary oocytes already formed, which may increase the risk of NONDISJUNCTION of chromosomes. See also DOWN'S SYNDROME.

o·o·cyte

(ō'ŏ-sīt)
Female gamete or sex cell.
[G. ōon, egg, + kytos, a hollow (cell)]

oocyte

an immature ovum; it is derived from an oogonium, and is called a primary oocyte prior to completion of the first maturation division, and a secondary oocyte between the first and second maturation division.
References in periodicals archive ?
1) Atresic volume fraction (AVF): the number of grid points occupied by AO divided by the total number of grid points occupied by all oocyte types.
Today, for women with premature ovarian failure or low ovarian reserve, the chance of pregnancy is recognized as realistic thanks to oocyte donation.
Moreover, 1,414 oocytes were collected from non-smoker couples while 1,280 oocytes were collected from smoker couples.
s study revealed that mouse oocyte vitrification did not affect the developmental competence and ATP content but some alterations were seen in mitochondrial distribution of in vitro matured oocytes compared with control group (38).
When the researchers irradiated mice lacking the CHK2 gene, the oocytes survived, eventually repaired the DNA damage, and the mice gave birth to healthy pups.
Oocyte maturation was evaluated at 24 hr by a stereomicroscope.
Microinjection of full-length and truncated Xpress-Egr3DsRed2 does not hinder oocyte maturation
26) The high concentrations found in follicular fluid are likely present to help counteract free radicals formed during oocyte maturation, as melatonin is a potent free radical scavenger.
Neither of these reported studies have evidence of heterogeneous oocyte development between lobes or within sections of the same lobe.
A potential role for triglyceride as an energy source during bovine oocyte maturation and early embryo development.
To obtain serum free IVM medium, bovine serum albumin (BSA) is an alternate source for oocyte maturation (Wydooghe et al.