When light activates a photoreceptor, what is the effect on the membrane potential of the cell?
A) depolarization
B) depolarization, followed by hyperpolarization
C) hyperpolarization
D) repolarization

Question

Quizplus · Accepted Answer

When light activates a photoreceptor, it causes hyperpolarization of the cell membrane. This is because light causes the closure of cGMP-gated ion channels, which leads to a decrease in the influx of sodium and calcium ions and an increase in the outflux of potassium ions, resulting in hyperpolarization of the cell membrane.

When Light Activates a Photoreceptor, What Is the Effect on the Membrane