B. testes - the Sertoli cells of the Testes are where sperm mature and the Leydig cells of the Testes generate Testosterone The vas deferens is a delivery tube connecting the testes to the prostate/urethra for export, and the penis is only a conduit to deliver the sperm inside semen during coitus. The epididymis only stores mature sperm in preparation for the next ejaculation.