oogonia


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Related to oogonia: oogenesis, polar body, primordial follicle

oogonium

(ō″ō-gō′nē-ŭm) plural.oogonia [″ + gone, seed]
1. The primordial cell from which an oocyte originates.
2. A descendant of the primordial cell from which the oocyte arises.

oogonia

The precursors of OOCYTES in the OVARY derived from primordial female germ cells that have migrated to the site of the ovaries.
References in periodicals archive ?
Within the same individual, alongside mature male gametes, female oogonia also develop (Coe 1931b).
Macrofossils--Characeae oogonia, shells of ostracods and molluscs--found in the lacustrine clay at the bottom of the Pantene/Brauksas I-2006 section, together with pollen of aquatic plants suggest that the clay was deposited in an oligotrophic lake during the late glacial.
The six ovaries used in this study ranged in age from 7 to 11 weeks postconception and contained only oogonia.
Sastry (1965), for instance, demonstrated that bay scallops require a minimum temperature for activation of the oocyte growth phase, and although oogonia can develop below this threshold, further differentiation only occurs at warmer temperatures.
A small minority of the remaining 600 valid histological specimens were bisexual juveniles with vestigial gonads containing chromatin nucleolar oogonia, undeveloped spermatic tissue, or both (Fig.
Oogonia were observed as round or ovoid cells and ranged from 15-20 [micro]m in diameter (Fig.
Oogonia and early oocytes were present with diameters of approximately 20 [micro]m and arranged along the oogenic follicle (Fig.
For an indeterminate spawner like sardine, where recruitment of new spawning batches of oocytes occurs continuously and directly from the oogonia, fast resorption is necessary because the aggregation of old POFs would restrict the space available for the development of new oocytes.
We also characterized 6 substages of oocyte and 2 structural indicators of spawning: oogonia (Po0), previtellogenic oocyte primary (Pol), previtellogenic oocyte secondary (Po2), vitellogenic primary oocyte (Vol).
In January, most clams were in the resting phase, although a small number of females showed small oogonia on their follicular epithelium.
The defining female characteristics were the formation of protogonial germ tissue into spherical germ cell nests, separation of a tissue layer from the outer epithelial layer of the lobe-forming ovarian walls, a tissue bud growing from the suspensory tissue that helped form the ovary wall, and the proliferation of oogonia and oocytes.