The opportunity for the natural exchange of nutrient-depleted surface water and nutrient-rich deep water is relatively high . a. in the Mediterranean
b. where salinity is equal
c. in warm waters
d. in tropical waters
e. where there is little or no thermocline

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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