Question

when potatoes are in the ground, do they swell with water when it rains? If not, how do you explain that, and if so, what would be the advantage or disadvantage?

Answer 1

I don't think they swell when they're in the ground and it rains, or else they cells within the root would burst. Cells must stay in an equilibrium with their surroundings, and that means that they could not swell after a rain. It would literally kill the potato, as silly as that sounds.