ANATOMY

Detailed explanation-1: -The internal urethral sphincter regulates involuntary control of urine flow from the bladder to the urethra, and the external urethral sphincter provides voluntary control of urine flow from the bladder to the urethra.

Detailed explanation-2: -Because the IUS is composed of smooth muscle, it is not under voluntary control. However, the IUS is controlled through the autonomic nervous system [17]. The IUS muscle controls the flow of urine by contracting around the internal urethral orifice.

Detailed explanation-3: -anal canal The internal sphincter is part of the inner surface of the canal; it is composed of concentric layers of circular muscle tissue and is not under voluntary control. The external sphincter is a layer of voluntary (striated) muscle encircling the outside wall of the anal canal…

Detailed explanation-4: -The internal urethral sphincter is located at the junction of the urethra and the urinary bladder. It is made of smooth muscle, and is under autonomic or involuntary control.

Detailed explanation-5: -Theinternal sphincter has both circular and longitudinal smooth muscle and is under involuntary control.