Nerves are cells that can detect any type of pressure, movement, or anything of that nature. If we didn't have nerves, we couldn't feel pain. If the nerves in a foot are damaged, you wouldn't feel the pain of it being burned.
Becuase the cell has a lower concentration that the solution it is placed in, the solution is considered hypertonic. The cell will lose water through osmosis and will shrink, the 2nd option is correct.
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