Fertilization in amphibians: the ancestry of the block to polyspermy.
D000663:Amphibians / Q000502:physiology*; D000818:Animals; D001001:Anura / Q000502:physiology; D005075:Biological Evolution; D005260:Female; D005306:Fertilization; D005399:Fishes / Q000502:physiology; D006801:Humans; D008297:Male; D009865:Oocytes / Q000166:cytology / Q000502:physiology; D013084:Sperm-Ovum Interactions; D013091:Spermatogenesis; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology; D014562:Caudata / Q000502:physiology