TOPICS: Urinary pathway, ejaculation pathway, seminiferous tubules, epididymis, ductus deferens, ejaculatory duct, prostatic urethra, membranous urethra, penile urethra, sperm, Sertoli cells, Leydig cells, inhibin B, MIF, androgen-binding protein, spermatozoa, testosterone, spermatogonia, spermatogenesis, spermatogonium, primary spermatocyte, meiosis I, secondary spermatocyte, meiosis II, spermatid, spermiogenesis, spermatozoon, emission, ejaculation, seminal vesicles, prostate gland, prostate specific antigen (PSA), bulbourethral gland, testicles, pudendal nerve, hypogastric nerve, erectile dysfunction, pelvic splanchnic nerves, PDE inhibitors, norepinephrine, androstenedione