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

Question

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

Quizplus · Accepted Answer

In the dark, cGMP keeps the sodium channels open in the rod cell membrane, allowing sodium ions to enter the cell. This influx of positive charge depolarizes the cell and leads to the release of neurotransmitters, which activate the downstream neurons and send the visual signal to the brain. Therefore, the best choice is A: open channels allow sodium to enter the cell.

When Rods Are in the Dark,cGMP Keeps Sodium Channels _________