[Achievements in the study of the development and ultrastructure of spermatozoa (on the 300th anniversary of the discovery of spermatozoa)].

A review of principal advances in studying spermiogenesis and fine structure of spermatozoa is given on the occasion of the 3rd centennary of the discovery of spermatozoa by Loevenhuk. The most important achievements are the discovery of acrosome and its role in fertilization, the discovery of centriole and its role in the formation of flagellum, the discovery of axial complex and the role of its components in the flagellum movement. A study of spermatogenesis has revealed the syncytial nature of spermatogenic epithelium, synaptinemal complexes and their role in chromosome conjugation. The role of nuclear membrane in chromosome conjugation was established, the ultrastructural and biochemical transformation of chromatin was investigated, as well as that of microtubules in spermatogenesis. Some other discoveries were made which are of great importance for diagnosis of sterility.