title: Ultrastructural studies of chiasma distribution.
mesh_terms: D000818:Animals; D012831:Bombyx / Q000235:genetics; D002875:Chromosomes / Q000648:ultrastructure; D003434:Crossing Over, Genetic; D004330:Drosophila / Q000235:genetics; D005260:Female; D005658:Fungi; D007313:Insecta; D008297:Male; D008540:Meiosis; D051379:Mice; D008854:Microscopy, Electron; D008954:Models, Biological; D013090:Spermatocytes / Q000648:ultrastructure