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The unisexual female sex organ in oogamous algae and fungi.
A descendant of a primary germ cell which develops into an oocyte.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the female sex organ (gametangium) of many lower plants that are characterized by oogamy. A single egg cell develops in the oogonium. Several egg cells rarely develop, for example, in Cyclosporeae brown algae. The oogonium is usually unicellular; less frequently, is it multicellular, for example, in Charophyta algae.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
AF = atretic follicle; CA = cortical alveolus; F = follicle cells; FG = fullgrown oocytes; Mi = micropyle; MO = maturing oocyte; N= nucleus/germinal vesicle; NC = nest of oogonia; Nu = nucleolus; OG = oogonium; OL = ovarian lumen; OW = ovarian wall; PG = primary growth oocytes; POC = postovulatory follicle complex; SG = secondary growth oocytes ; Y = yolk globules; ZP = zona pellucida.
During stage I, the ovary contained mainly oogonium, and many follicle cells were distributed among germinal zones.
The presence of oocytes, from oogonium to hydrated oocytes, was observed on the histological analyses, characterizing multiple spawning, and the monthly distribution of gonad stages indicated higher percentage of females on ripe and spent through November to April (Fig.
It could provide technical support for the basic research on regulation of c-FLIP(L) on the bovine oogonium development, and be important for further research.
Primary oocyte An intermediate cell type in oogenesis arising from an oogonium and remaining in the first meiotic prophase until ovulation.
After fertilization of an oogonium, the resulting oospore was retained on the female thallus and underwent a number of cell divisions to produce a multicellular 'fruit'.
Abbreviations: AO, amitotic oogonium; AS, amitotic spermatogonia; BPB, mercuric bromophenol blue; C, coelom; CG, cortical granules; DPO, degenerating primary oocyte; FGPO, fully grown primary oocyte; GHS, genital hemal sinus; GI, gonad index; LSS, later spermatogenic stages; MS, mitotic spermatogonia; MYP, major yolk protein; NP, nutritive phagocyte; NPIC, nutritive phagocyte incubation chamber; NS, new spermatozoa; NVPO, new vitellogenic primary oocyte; O, ovum; OL, ovarian lumen; PAS, periodic acid Schiff; RIC, residual NP incubation chamber; RVPO, residual vitellogenic primary oocyte; RSC, residual spermatogenic cells; TL, testicular lumen.
Mature oogonia are cleaved into eight eggs that remain tightly packed inside the oogonium. The total numbers of oogonia did not decline significantly between 23-24 March (prior to release) and 25-26 March (when release occurred), although there were fewer in samples taken on 27 March ([ILLUSTRATION FOR FIGURE 2 OMITTED], left axis: ANOVA, [F.sub.5,48] = 3.18; P [less than] 0.02).