General Considerations

Abstract

Mammalian spermatozoa are small and motile and show a general uniformity in their internal and external structure. The spermatozoon, which performs the function of carrying genetic material from the male to the oocyte, consists of two principal parts, such as the head and the tail (Fig. 55). The tail consists of four components, such as the neck, mid-piece, principal piece, and end-piece (Phillips 1975a). The cytoplasmic droplet is present in association with the mid-piece of immature spermatozoa (Fig. 17). Silver nitrate can differentiate many of the gross morphological features of spermatozoa, including the acrosome, subacrosomal region, perforatorium, post-acrosomal sheath, neck, dense outer fibres of the core of the mid-piece, annulus, principal piece, and end-piece (Elder and Hsu 1981). Silver-staining patterns of spermatozoa have revealed both species-specific and strain-specific differences, especially of the sperm head.