How does craving a cookie relate to diffusion

You craving that cooking would mean that the smell of the cookie enticed you had a higher concentration smell inside the cookie jar so the smell left the jar to lower condentration in open to in order to have and equilibrium in concentration smells thus leading it to your nose causing you my friend to crave that cookie.

Explanation:

Diffusion is the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration. The difference in the concentrations of the molecules in the two areas is called the concentration gradient.

I hoped that was clearer now

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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