Osmosis which is a form of passive transport

represents the flow of water through its concentration gradient, through a semi-permeable membrane.

Explanation:

This means that water flows from where it is in a higher concentration to a place where it is in a lower concentration to try to equalize the concentrations of both solutions.

Osmosis is an example of diffusion when molecules tend to be evenly distributed in space.

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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