Development of spermatozoa in the wooly opossum with special reference to the shaping of the sperm head.
D000818:Animals; D002462:Cell Membrane; D002467:Cell Nucleus; D003593:Cytoplasm; D008297:Male; D008854:Microscopy, Electron; D008870:Microtubules; D008928:Mitochondria; D009893:Opossums; D012708:Sertoli Cells; D013094:Spermatozoa / Q000166:cytology* / Q000254:growth & development