The external urethral sphincter
A)surrounds the external urethral orifice.
B)is composed of smooth muscle fibers.
C)is controlled by the somatic nervous system.
D)opens before the internal urethral sphincter during the micturition reflex.
E)All of the choices are correct.

Question

Quizplus · Accepted Answer

The external urethral sphincter is controlled by the somatic nervous system, which means it is under voluntary control. The other options are not correct: A is true but not the best answer as the question is asking about the function, not location. B is incorrect as the external urethral sphincter is composed of skeletal muscle fibers, not smooth muscle fibers. D is also incorrect as the internal urethral sphincter opens before the external sphincter during the micturition reflex.

The External Urethral Sphincter