What part of the plant cell gets bigger due to osmosis?

When water enters a cell, it expands.  This creates turgor pressure on the walls of a plant cell and can cause the cell to explode because of the heavy absorption of fluid. This is also known as turgidity.

Explanation:

Plant cells are encompassed by a rigid cell wall and when the plant cell is put in a hypotonic solution, it takes up water through osmosis. It obviously starts to swell at this point, but the cell wall prevents it from ultimately bursting. The plant cell is said to have become 'turgid' or swollen and hard.

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