What occurs during an action potential in a neuron?

During an action potential in a neuron, the process begins when a stimulus causes the membrane potential to reach a threshold level. This triggers the opening of sodium channels, allowing sodium ions to rush into the cell. The influx of sodium contributes to a rapid depolarization of the neuron, which is a critical aspect of the action potential. Once the membrane potential reaches a peak, potassium channels open, allowing potassium ions to flow out of the cell. This efflux of potassium is responsible for repolarizing the neuron back towards its resting potential.

The option detailing the behavior of sodium channels opening, followed by the opening of potassium channels, accurately encapsulates the sequence of events that define the action potential. This sequence is vital for the propagation of electrical impulses along the neuron and ultimately communicates signals throughout the nervous system.