Question

two fundamental concepts about the ion channels of a
esting\ neuron are that the channels are always open, but the concentration gradients of ions frequently change. open and close depending on chemical messengers and are nonspecific as to which ion can traverse them. open and close depending on stimuli and are specific as to which ion can traverse them. are always closed, but ions move closer to the channels during excitation. open in response to stimuli and then close simultaneously, in unison.

Explanation:

Ion - channels in a resting neuron are gated, meaning they open and close depending on stimuli like electrical or chemical signals. They are also ion - specific, allowing only certain ions to pass through. For example, voltage - gated sodium channels open in response to a change in membrane potential and allow sodium ions to enter the neuron.

Answer:

open and close depending on stimuli and are specific as to which ion can traverse them.