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C.A. Edwards

Publications and source records attributed to C.A. Edwards.

6 recordsLinked to original sources
USGS1996

Comparative morphology of zebra ( Dreissena polymorpha ) and quagga ( Dreissena bugensis ) mussel sperm: Light and electron microscopy

Adult zebra ( Dreissena polymorpha ) and quagga ( Dreissena bugensis ) mussels were induced to release large quantities of live spermatozoa by the administration of 5-hydroxytryptamine (serotonin). Sperm were photographed alive using phase-contrast microscopy and were fixed subsequently with glutaraldehyde followed by osmium tetroxide for eventual examination by transmission or scanning electron microscopy. The sperm of both genera are of the ect-aquasperm type. Their overall dimensions and shape allow for easy discrimination at the light and scanning electron microscopy level. Transmission electron microscopy of the cells reveals a barrel-shaped nucleus in zebra mussel sperm and an elongated nucleus in quagga mussel sperm. In both species, an acrosome is cradled in a nuclear fossa. The ultrastructure of the acrosome and axial body, however, is distinctive for each species. The structures of the midpiece are shown, including a unique mitochondrial "skirt" that includes densely packed parallel cristae and extends in a narrow sheet from the mitochondria.

Canadian Journal of Zoology↗