Ion Channels on Photoreceptors That Open or Close Due to Cyclic

Multiple Choice

Ion channels on photoreceptors that open or close due to cyclic guanosine monophosphate (cGMP) are responsible for maintaining the photoreceptor's resting membrane potential, which is usually about

A) -80 mV, until it is depolarized by light.
B) -40 mV, until it is depolarized by light.
C) -80 mV, until it is hyperpolarized by light.
D) -40 mV, until it is hyperpolarized by light.
E) -20 mV, until it is hyperpolarized by light.