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SAUL WISCHNITZER
The site of formation of the cortical granules was, until recently, unclear.
Thus, Kemp (1956) felt that they arise in situ in the peripheral cytoplasm.
Balinsky and Devis (1963) have concluded from their studies on Xenopus
that the Golgi complex is intimately associated with the formation of the
/
V
Very early oocyte
Maturing oocyte
Early oocyte
FM
.via?."VV:
··- .
I
Fertilized egg
FIG. 22. A diagrammatic representation of the formation of cortical granules
from the small vesicles of the Golgi complex. SE, surface epithelium; T, theca;
FE, follicle epithelium; p, plasmalemma; Gc, Golgi complex; ZP, zona pellucida;
Cg, cortical granules; VM, vitelline membrane; PS, perivitelline space; FM, fertilization membrane; mac, macrovilli; mic, microvilli.
cortical granules. Their synthesis appears to take place throughout the
outer third of the cytoplasm, during a considerable period of oocyte growth.
Cortical granule formation is initiated when vitellogenesis begins (oocyte
diameter of ~200 μ) and lasts until the time when large amounts of yolk
fill the cytoplasm (oocyte diameter of ~500 μ).