title: Premature sperm incorporation into the primary oocyte of the polychaete Pectinaria: male pronuclear formation and oocyte maturation.
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D008297:Male; D008854:Microscopy, Electron; D009865:Oocytes / Q000502:physiology* / Q000648:ultrastructure; D010063:Ovum / Q000502:physiology*; D011077:Polychaeta / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology*