in the present study, a total of 595 specimens collected monthly in the northern part of persian gulf between november 2006 and october 2007 were examined by routine macroscopic and histological techniques. monthly changes in the gonadosomatic index showed the spawning season extended within 2 peaks, from april- may and september. the maturity stages are morphologically separated according to t...

Cortical granules are secretory vesicles poised at the cortex of an egg that, upon stimulation by sperm contact at fertilization, secrete their contents. These contents modify the extracellular environment and block additional sperm from reaching the egg. The role of cortical granules in blocking polyspermy is conserved throughout much of phylogeny. In the sea urchin, cortical granules accumula...