Question:
Hello,
I read that the prostate is a muscle-driven switch. It stops semen from entering the bladder, but how does it prevent urine from entering the ejaculatory ducts? I have searched on Google and Microsoft and I found nothing about this. Is there a valve in the ejaculatory ducts or what?
Answer:
“During ejaculation, the prostate and the bladder’s sphincter muscle close the urethra up to the bladder to prevent semen from entering the bladder. Closing of the seminal ducts during urination: During urination, the central zone muscles close the prostate’s ducts so that urine cannot enter” [“How does the prostate work?“, National Library of Medicine, 15 February 2011].
Sphincter muscles surround a tube, such as the urinary duct or the ejaculatory duct. When the muscles contract, they squeeze the duct close.