Question

All of the following describe the molecular/cellular changes that occur in cones in response to light, except one. Choose the exception. Group of answer choices a) Hyperpolarization of membrane potential b) Reduction in the release of the neurotransmitter glutamate from cone synaptic terminals c) Activation of transducin d) Inactivation of phosphodiesterase.

Answer 1

Answer:

The exception is d) Inactivation of phosphodiesterase

Explanation:

In the presence of light:

a) The membrane potential of the photoreceptors is hyperpolarized, causing a reduction in the amount of neurotransmitter released by the photoreceptor terminal to the postsynaptic neurons

b) Sodium ions accumulate outside the plasma membrane and the receptor potential takes a form

of hyperpolarization 6. This change in membrane potential leads to the closure of calcium channels. The end result is a decrease in the secretion of the neurotransmitter glutamate by the photoreceptors

c) Visual transduction or phototransduction is the process by which a light photon generates a nervous response in the photoreceptors

d) As a consequence of phosphodiesterase activation, degradation of a molecule called cGMP (guanosine cyclic monophosphate) is stimulated