SPERMIOGENESIS IN CANCER CRABS
نویسندگان
چکیده
منابع مشابه
Spermiogenesis in Cancer Crabs
Spermiogenesis in Cancer crabs was studied by light and electron microscopy. The sperm are aflagellate, and when mature consist primarily of a spherical acrosome surrounded by the nucleus with its short radiating arms. The acrosome forms by a coalescence of periodic acid-Schiff-positive (PAS-positive) vesicles. During spermiogenesis one edge of the acrosomal vesicle invaginates to form a PAS-ne...
متن کاملSpermiogenesis in Lumbricus herculeus
Small pieces of the sperm sacs of Lumbricus herculeus were fixed for 4 hours in chrome-osmium, embedded in methacrylate, sectioned with a Porter-Blum microtome, and studied with a R.C.A. EMU-2C electron microscope. Each spermatid of a group developing synchronously is attached by a cytoplasmic strand to a common nutrient protoplasmic mass. This mass contains mitochondria and yolk bodies but is ...
متن کاملSpermiogenesis in birds
Current knowledge on avian spermiogenesis, including strengths and weaknesses, has been reviewed. Information on avian spermiogenesis considerably lags behind that in mammals because of the paucity of reports in birds. Spermiogenesis in passerine birds has received even much less attention than in non-passerine birds. Mechanisms underlying morphogenesis of the acrosome and nucleus, and roles of...
متن کاملDrosophila spermiogenesis
Drosophila melanogaster spermatids undergo dramatic morphological changes as they differentiate from small round cells approximately 12 μm in diameter into highly polarized, 1.8 mm long, motile sperm capable of participating in fertilization. During spermiogenesis, syncytial cysts of 64 haploid spermatids undergo synchronous differentiation. Numerous changes occur at a subcellular level, includ...
متن کاملVision in Horseshoe Crabs
Limulus has been a superb animal model for understanding vision in higher animals, including man. Nobel-prize winning research on the lateral eye of Limulus by H. K. Hartline revealed fundamental principles of retinal function applicable to all eyes. The function of the Limulus lateral eye is now well understood as is its essential role in the animal’s mating behavior.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Cell Biology
سال: 1969
ISSN: 1540-8140,0021-9525
DOI: 10.1083/jcb.43.3.575