When the bladder wall is distended as a result of urine accumulation, the stretch receptors are stimulated and send afferent impulses to the spinal cord that
A) stimulate parasympathetic nerves, which return to the bladder and cause it to contract.
B) inhibit the motor neurons that normally keep the external urethral sphincter closed.
C) stimulate nerves that go to the kidney and prevent glomerular filtration until the bladder is empty.
D) both (a) and (b) above.
E) all of these answers.

Question

Quizplus · Accepted Answer

The stretch receptors in the bladder wall send afferent impulses to the spinal cord, which stimulates parasympathetic nerves that return to the bladder and cause it to contract (response A) and also inhibits the motor neurons that normally keep the external urethral sphincter closed (response B). Therefore, both responses A and B are correct. Response C is incorrect, as there is no connection between the bladder and kidney in this reflex arc. Therefore, the best answer is D.

When the Bladder Wall Is Distended as a Result of Urine