Electron Microscopy on Sea Urchin Gametes

acrosomal filament acrosomal globule acrosomal reaction AFZELIUS Anat annuli Arbacia egg Bernhard Biochem Biol Biophys BRADFIELD brush border CARASSO cell component cell membrane Cell Research cell types centrifugation centriole clear cytoplasm COLWIN cortex cortical cytoplasm cortical granules Cortical reaction Cytol cytoplasmic membranes diameter dictyosomes double membrane droplet egg surface egg water electron micrographs electron microscope endoplasm Exptl fertilization membrane FINEAN fixation fixed Golgi elements GRASSÉ HARVEY heavy bodies homogeneous inclusions inner membranes investigation isolated Janus green limiting membrane living cell living spermatozoa material mature egg middle piece mitochondria nuclear membrane nucleolus nucleoplasm oocyte nucleolus osmiophilic osmium tetroxide particles pigment vacuoles polyspermy present study Proc protoplasm Psammechinus miliaris sea urchin egg sea urchin gametes sea urchin oocyte sea urchin spermatozoon sea water sections similar small granules species sperm spermatids staining Stockholm structure tail filaments tion tozoon unfertilized egg vesicles vitelline membrane yolk granules yolk nuclei Zellforsch