The hypothalamus causes the anterior pituitary to secrete hormones by
a--nervous stimulation.
b--releasing hormones.
c--negative feedback.
d--releasing adrenalin.

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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it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added

answer; endometriosis;