Which gland contains a valve that controls whether urine or sperm enters the urethra?

The prostate gland is responsible for producing a fluid that nourishes and transports sperm, and it also plays a crucial role in controlling the passage of urine and sperm through the urethra. It features a valve-like mechanism known as the prostatic urethra, which helps regulate whether urine or semen is allowed to pass through. During ejaculation, this valve closes off the bladder, preventing urine from mixing with semen, ensuring that only sperm is released through the urethra. This anatomical feature underscores the prostate's essential function in male reproductive health.

Other glands mentioned have different functions: the seminal vesicle primarily contributes fluid to semen, while the bulbourethral gland produces a pre-ejaculatory lubricating fluid. The testis is responsible for sperm production and hormone secretion but does not have a role in controlling fluid passage into the urethra.