In the figure below, panel a shows a photoreceptor and its postsynaptic cell in the dark, and panel b shows both cells in the light. What causes the change observed in this figure?
A)Hyperpolarization of the rod cell in the dark causes release of a neurotransmitter.
B)Hyperpolarization of the rod cell in the light inhibits release of a neurotransmitter.
C)Depolarization of the rod cell in the light inhibits release of neurotransmitter.
D)This figure is incorrect; dark and light are reversed.

Question

In the figure below, panel a shows a photoreceptor and its postsynaptic cell in the dark, and panel b shows both cells in the light. What causes the change observed in this figure? 
A)Hyperpolarization of the rod cell in the dark causes release of a neurotransmitter. 
B)Hyperpolarization of the rod cell in the light inhibits release of a neurotransmitter. 
C)Depolarization of the rod cell in the light inhibits release of neurotransmitter. 
D)This figure is incorrect; dark and light are reversed.

Quizplus · Accepted Answer

In the dark, the rod cell is depolarized and releases a neurotransmitter onto the postsynaptic cell. In the light, the rod cell is hyperpolarized, which inhibits the release of neurotransmitter onto the postsynaptic cell. Therefore, the change observed in the figure is due to the inhibition of neurotransmitter release in response to hyperpolarization of the rod cell in the light.

In the Figure Below, Panel a Shows a Photoreceptor and Its