AP PSYCHOLOGY

Detailed explanation-1: -Action potential is a brief reversal of membrane potential where the membrane potential changes from-70mV to +30mV. When the membrane potential of the axon hillock of a neuron reaches threshold, a rapid change in membrane potential occurs in the form of an action potential.

Detailed explanation-2: -For example, if the neuron is at resting potential (-70mV) and the conductance to sodium increases, the membrane potential will be depolarized (it will move toward +55mV). When the conductance to sodium goes back to its original value, the membrane potential will return to the resting potential.

Detailed explanation-3: -A neuron at rest is negatively charged: the inside of a cell is approximately 70 millivolts more negative than the outside (−70 mV, note that this number varies by neuron type and by species).

Detailed explanation-4: -This is called repolarization, meaning that the membrane voltage moves back toward the-70 mV value of the resting membrane potential. Repolarization returns the membrane potential to the-70 mV value of the resting potential, but overshoots that value.