oocyte


Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to oocyte: oogenesis, Oocyte donation, OoCyte Retrieval, primary oocyte, Oocyte maturation

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 ?
During maturation, the migration of CGs to the cortex relies on microfilament assembly, and a peripheral CG distribution is one indication of oocyte maturity.
In their first conventional ICSI attempt, 26 oocytes were collected, 3 embryos were transferred and following OHSS, she had negative P hCG value.
Automated two electrode voltage clamp system for electrophysiology recordings from Xenopus oocytes.
b) Workers covered their hair, mouth and nose, and used disposable hoods whenever conducting oocyte and embryo culture techniques.
Final estimates of total oocyte number, clutch size, and clutch mass, however, include only the number of MA and MR oocytes from MA and MR females because some RE eggs from RE females may have been spawned prior to capture (Heins and Baker, 1993a).
To address the concern over the potential for differential oocyte distribution throughout the ovary, additional samples were collected from the anterior and posterior ends of the ovary.
Effects of low methyl donor levels in culture medium during mouse follicle culture on oocyte imprinting establishment.
3C and 4C): A large interval of different oocyte sizes in all gametogenic stages are observed, including some free oocytes.
A single layer of oocyte clusters projects from the ovigerous membrane to the lumen (Fig.
Vitrification uses high concentrations of cryoprotectants and an extremely high cooling rate (-20,000- 25,000 [euro]centsC per minute) that solidify without the formation of ice crystal by direct immersion into liquid nitrogen in order for the oocytes to be transitioned from 37[euro]centsC to -196[euro]centsC in less than one second and can be stored for future use.
Cysteamine is a thiol that increased GSH and promoted male pronucleus formation in porcine oocyte.
However, in contrast to the embryo, the oocyte is more sensitive to the cryopreservation process owing to its high water content, which predisposes it to damage caused by ice crystal formation.