Spermatogonia - Spermatozoa

In a cross-section of the seminiferous tubule you will find that spermatogonia are located just inside the basement membrane of the tubules, and the series of maturing stages i.e. from spermatogonia-spermatozoa, occur towards the lumen where mature sperms are released. Studies have indicated that in man it requires' about 74 days for a spermatogonium to transform into functional spermatozoa. The rate of germ cell development is constant for a given species and strains of mammals, and that this rate cannot be accelerated by hormones.

Cytological observations suggest that germ cells must move forward during their differentiation; if unfavourable environment make it impossible for them to pursue their differentiation at the normal fate, they degenerate and are eliminated from the system. Although hormones do not accelerate the rate of germ cell differentiation. they must contribute to the creation of favourable environments for their transformation into the spermatozoa.