What happens to a population when immigration increases? A. The population size usually increases.
B. The emigration rate usually increases.
O C. The emigration rate usually decreases.
O D. The population size usually decreases.

the answere is D bc the more people leave the less they will be

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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