The answer is stem cells. Normal stem cells and germ cells can also be said to be immortal
I think salt is it
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Answer:
The cell would lose the water inside it causing it to die.
Explanation:
Water in cells moves towards the higher concentration of salt so if there is more on the outside the water would move on the outside causing it to die because it needs water. If it was the opposite and there was more salt inside more water would go inside causing the cell to swell and virtually exploding and diluting parts of our body.