title: Electron microscopic study of the membranes of bull spermatozoa and spermatids, with reference to the postacrosomal cap and the basal knobs.
mesh_terms: D000177:Acrosome / Q000648:ultrastructure; D000818:Animals; D002417:Cattle / Q000033:anatomy & histology*; D002462:Cell Membrane / Q000648:ultrastructure; D008297:Male; D013087:Spermatids / Q000648:ultrastructure; D013094:Spermatozoa / Q000648:ultrastructure*