When a single photon from a source of light hits the retina in the eye, it triggers a signal that travels along the optic nerve to the occipital lobe of the brain.

The interaction of a photon with the photoreceptors in the retina first causes the movement of sodium ions into a sensory neuron. What happens after the movement of sodium ions?

Select one:

a. Potassium ions move into an interneuron.

b. Potassium ions move out of a sensory neuron.

c. Sodium ions move out of a sensory neuron.

d. Sodium ions move into an interneuron.