What is a group of organisms that belong to a same species

The organisms which belong to the same species in any specific locality are named as a population. A population is a number or a group of all the organisms belonging to the same group or species living in a specific geographical area and are capable of interbreeding and reproducing to produce similar offspring.

Explanation:

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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