Male urethral sphincters
Males have two sphincters:
Bladder internal/neck sphincter, smooth muscle is continuous with the detrusor muscle and is under involuntary control or autonomic control; the function of this sphincter is to keep the bladder closed at the time of ejaculation.
External bladder neck sphincter, striated/skeletal muscle at the base of the prostate and is under voluntary control of the somatic nervous system. This muscle can be exercised and will strengthen with pelvic floor exercises. Figure 2.3: Male bladder showing the position where the ureters enter the bladder, the trigone and the bladder sphincters.
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