Name

# Sphincter of the Urethra (superficial part)

Pronunciation

(sfingk-ter) of the (yO-rE-thra)

Notes

The flow of urine from the urinary bladder is controlled by a group of muscles collectively called the urethral sphincter, named for their proximity to the urethra. Both sexes have at least two areas of muscle: the internal sphincter, or bladder neck; and the external, or distal, sphincter.

In males the internal and external urethral sphincters are more powerful, able to retain urine for twice as long as females, and are furthermore backed up by the tertiary rings of urethral sphincters along the length of the penis.