Coal is formed when layers of plant matter accumulate at the bottom of a body of water and are protected from biodegradation and oxidization. over time, the properties of the original material change. what evolutionary significance, if any, does this have?

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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