Anatomy, Abdomen and Pelvis, Male Genitourinary Tract

The male genitourinary tract is responsible for the excretion of urine, produced by the kidney, and semen from the sperm from the testes and the various accessory glands. The urethra serves as the final path of excretion of both urine and semen from the body. See Male Genitourinary Tract. Urine is the waste product of filtered blood that leaves the kidney via the collecting system. From the renal collecting system, urine is transported through the ureters and stored in the urinary bladder for elimination through the urethra. Sperm is produced in the testes and undergoes maturation in the epididymis. During ejaculation, sperm moves through the epididymis to the vas deferens. The vas deferens is the duct for transporting sperm from the epididymis. It is in the scrotal sac and passes through the inguinal canal into the abdominopelvic cavity. As the vas deferens course to the posterior portion of the prostate, they join the seminal vesicles. The seminal vesicle ducts add seminal fluid to the ejaculate. The area of convergence of the seminal vesicles and vas deferens forms the ejaculatory ducts.  The ejaculatory ducts enter the prostate and empty into the prostatic urethra. Within the prostatic urethra, additional secretions from the prostate gland itself are added to the seminal fluid. The final addition of ejaculatory fluid is a lubricating mucus from the bulbourethral glands, located in the membranous urethra. At ejaculation, the semen leaves through the urethra.