When rods are in the dark, cyclic guanosine monophosphate (cGMP) keeps sodium channels _________ allowing sodium to _________ the cell.
A) open; enter
B) open; leave
C) closed; enter
D) closed; leave

Question

Quizplus · Accepted Answer

In the dark, cyclic guanosine monophosphate (cGMP) keeps sodium channels open, allowing sodium ions to enter the cell, which is crucial for the dark current in photoreceptor cells.

When Rods Are in the Dark, Cyclic Guanosine Monophosphate (CGMP)