In the context of neuron activity, what occurs when neuron X is depolarizing and neuron Y is undergoing an action potential?

In the context of neuron activity, what occurs when neuron X is depolarizing and neuron Y is undergoing an action potential?

• A. Ligand-gated chloride ion channels are opening in neuron X, whereas voltage-gated potassium ion channels are opening in neuron Y
• B. Voltage-gated potassium ion channels are opening in neuron X, whereas ligand-gated chloride ion channels are opening in neuron Y
• C. Ligand-gated sodium ion channels are opening in neuron X, whereas voltage-gated sodium ion channels are opening in neuron Y
• D. Voltage-gated sodium ion channels are opening in neuron X, whereas ligand-gated sodium ion channels are opening in neuron Y

Answer: (C)

In the process of neural communication, depolarization in a neuron refers to a change in the membrane potential that makes the inside of the neuron more positive relative to the outside, generally in preparation for firing an action potential. When neuron X is depolarizing, it indicates that there is an increase in sodium ion permeability, often due to the opening of sodium ion channels, particularly ligand-gated sodium channels. These channels open in response to neurotransmitter binding, allowing sodium ions to flow into the cell, further contributing to depolarization. Simultaneously, neuron Y experiencing an action potential indicates that it has reached its threshold potential, and voltage-gated sodium channels are opening rapidly. This influx of sodium ions occurs almost instantly, causing the rapid depolarization phase of the action potential. This explanation clarifies that both neurons are actively engaging in different yet complementary stages of electrical signaling: neuron X is in the phase of increased sodium permeability due to ligand-gated sodium channels, while neuron Y is undergoing its action potential due to the activity of voltage-gated sodium channels. Thus, option C identifies the correct events corresponding to the states of both neurons.

In the process of neural communication, depolarization in a neuron refers to a change in the membrane potential that makes the inside of the neuron more positive relative to the outside, generally in preparation for firing an action potential. When neuron X is depolarizing, it indicates that there is an increase in sodium ion permeability, often due to the opening of sodium ion channels, particularly ligand-gated sodium channels. These channels open in response to neurotransmitter binding, allowing sodium ions to flow into the cell, further contributing to depolarization.

Simultaneously, neuron Y experiencing an action potential indicates that it has reached its threshold potential, and voltage-gated sodium channels are opening rapidly. This influx of sodium ions occurs almost instantly, causing the rapid depolarization phase of the action potential.

This explanation clarifies that both neurons are actively engaging in different yet complementary stages of electrical signaling: neuron X is in the phase of increased sodium permeability due to ligand-gated sodium channels, while neuron Y is undergoing its action potential due to the activity of voltage-gated sodium channels. Thus, option C identifies the correct events corresponding to the states of both neurons.