After their manufacture, sperm cells are stored in a much-coiled tube on the surface of each testis, the epididymis. Here they remain until ejaculation propels them into a series of ducts that lead out of the body. The first of these is the vas (ductus) deferens. This duct ascends through the inguinal canal into the abdominal cavity and travels behind the bladder. A short continuation, the ejaculatory duct, delivers the spermatozoa to the urethra as it passes through the prostate gland below the bladder. 

Finally, the cells, now mixed with other secretions, travel in the urethra through the penis to be released. The penis is the male organ that transports both urine and semen. It enlarges at the tip to form the glans penis, which is covered by loose skin, the prepuce or foreskin. Surgery to remove the foreskin is circumcision. This may be performed for medical reasons, but is most often performed electively in male infants for reasons of hygiene, cultural preferences, or religion.

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