Zona radiata

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(Biol.) a radiately striated membrane situated next the yolk of an ovum, or separated from it by a very delicate membrane only.

See also: Zona

Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
The first visible sing of atresia in vitellogenic oocytes (stage 5 atretic oocytes), was the thickening of the zona radiata. In advance stage five atretic oocytes, yolk liquefaction, zona radiata breakdown, yolk releasing and hypertrophy of the granulosa were observed (Fig.
Their diameters at the early stage ranged from 218 to 359 [micro]m and had a zona radiata width of 2-3 [micro]m (Fig.
A membrana basal e delgada e a zona radiata e mais espessa que nas fases anteriores (Figura 1D), com celulas foliculares apresentando forma de pavimentosa a cubica.
Los cambios macroscopicos (aumento de tamano y de la vascularizacion, cambios en la coloracion y textura) fueron acompanados por grandes modificaciones histologicas durante el desarrollo de los ovocitos (formacion de la zona radiata, envoltura folicular, membrana basal y teca), que fueron achatados y elongados en hembras inmaduras y voluminosos en el periodo de maduracion avanzada.
Fish zona radiata (eggshell) protein: a sensitive biomarker for environmental estrogens.
Besides cytoplasmic vacuolization, opening between zona radiata and follicular epithelium were monitored (Fig.