What are male germ cells?

Male germ cells are the cells in testes that form sperm: they start as spermatogonia and develop into spermatocytes, spermatids, and finally spermatozoa.

In seminiferous tubules, stem-like spermatogonia divide by mitosis. Some remain as a reserve; others become primary spermatocytes that enter meiosis. After two meiotic divisions they form haploid spermatids, which remodel during spermiogenesis (acrosome formation, flagellum growth, nuclear condensation) to become spermatozoa. Sertoli cells support and nourish all stages, and Leydig cells outside the tubules produce testosterone to regulate the process.