Spermatogenesis

Spermatogenesis

1. Mitotic Proliferation

   • Produces large numbers of stem cells which begin maturation at puberty where further mitotic divisions produce Type A spermatogonia
   • Occurs in basal part of tubule. Stem cells along with mesodermal cells form seminiferous cords in developing testis.
   • Spermatogonia are diploid and genetically identical. Some type A spermatogonia will further divide to type B from which primary spermatocytes arise.
     • Meiotic proliferation
       • Generates genetic diversity (chromatids exchange genetic material - crossover)
       • Halves chromosome number (haploid)
       • Spermatocytes become spermatids
         • Cytodifferentiation (Spermiogenesis)
           • Packages genes for delivery to oocyte
           • Elongating spermatids to spermatozoa
           • Spermiogenesis changes
             • Spermiogenesis
       • Occurs in adluminal compartment of tubule