Final answer:
Spermatogonia divide mitotically to produce primary spermatocytes, which then undergo meiosis I to become secondary spermatocytes. These secondary spermatocytes divide once more during meiosis II to become spermatids, which mature into sperm cells.
Step-by-step explanation:
Spermatogonia become primary spermatocytes through the process of mitosis. Initially, a spermatogonium, which is a diploid stem cell, divides mitotically to produce two identical diploid cells. One of these cells retains its status as a spermatogonium to maintain the stem cell population, while the other cell differentiates into a primary spermatocyte.
Following mitosis, the primary spermatocyte undergoes a critical phase of meiosis I, where it divides to form two haploid secondary spermatocytes. Each of these secondary spermatocytes then progresses through meiosis II to produce two spermatids each, resulting in a total of four haploid spermatids from a single primary spermatocyte. These spermatids will eventually mature into sperm cells.
It's essential to understand that this process occurs within the seminiferous tubules of the testes, where the least mature cells, the spermatogonia, line the basement membrane, and spermatozoa are located near the lumen. Spermatogonia are capable of undergoing this sequence of differentiation across the male's reproductive lifespan. The intricacy of spermatogenesis ensures that each resulting sperm is genetically unique, an important factor for genetic diversity.