While water molecules are polar, they are also very small. One fact not mentioned in the video is that some (but not most) water molecules are able to squeeze directly through the phospholipid bilayer due to their small size. This is an example of which of the following?

simple diffusion

active transport

facilitated diffusion

semidiurnal tides is !

i did this and it was !

answer; (phospholipid);

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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