So deep inside the wall of our seminar phil's tubule are the stem cells of the male gonas known as spermatogonium. Now, spermatogonium are diploid cells and that means in humans the chromosome number of spermatogonium is 46. So when lathic cells produce our testosterone, it stimulates the spermatogonium to differentiate into the primary spermatocyte, also a diploid cell. So the primary spermatocyte also contains 46 chromosomes. Now, the primary spermatocide can now undergo meiosis one. And what undergoes meiosis one?