Why does the chair in which you are currently sitting retain its same shape over time?
question options:
the particles of the chair are strongly held together.
the chair is lower in energy than the surrounding environment.
the particles of the chair are free to move and form their most stable positions.
the chair is made of particles that are relatively far apart and spread out to a maximum to form the chair shape.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.