Spermatogonium is an undifferentiated male germ cell. Humans have three types: dark (stem) and pale (mitotic) cells. Type B cells differentiate into primary spermatocytes
Vas deferens is part of male reproductive system, measuring 30-35 cm in length. Forms part of spermatic cord, connecting epididymis to ejaculatory duct. Contains external adventitial sheath, muscular middle layer, and mucosal lining. Has greatest muscle-to-lumen ratio among hollow organs
Two small exocrine glands located near urethra below prostate. Each gland is pea-sized, up to 18 cm long in boars. Composed of lobules with acini lined by columnar epithelial cells. Enclosed by sphincter urethrae membranaceae muscle fibers
Testicular atrophy causes testicle size reduction and reduced function. Symptoms include reduced testosterone levels and sexual characteristics. Prepubescent patients show underdeveloped secondary sex characteristics. Postpubescent patients experience lower sex drive and increased breast tissue
Scrotum is a sac of skin containing testicles and spermatic cords. Located behind penis and above perineum. Divided into two cavities by connective tissue septum. Contains testicular artery, vein, and pampiniform plexus
Penis consists of root, body and glans. Contains three erectile tissues: two corpora cavernosa and corpus spongiosum. Root is fixed to pubic symphysis via suspensory ligaments. Body contains urethra and penile neurovascular bundle