Question

which of the following is incorrect about erection?
a autonomic nerves release nitric oxide.
b cgmp is produced that causes artery walls to relax.
c arteries entering the penis constrict.
d veins that exit the penis are compressed.

Explanation:

During erection, autonomic nerves release nitric oxide (A is correct). Nitric oxide leads to the production of cGMP, which causes artery walls to relax (B is correct). When artery walls relax, arteries entering the penis dilate, not constrict (C is incorrect). Also, veins that exit the penis are compressed (D is correct) to maintain the erection.

Answer:

C. Arteries entering the penis constrict.