Vacuoles are membrane-bound compartments that can be found in eukaryotic cells. Eukaryotic cells are cells that contain membrane-bound organelles, such as a vacuole, and a nucleus. Plants, animals, and fungi are composed of eukaryotic cells.
Vacuoles serve to hold water and nutrients within a cell. Vacuoles also protect cells by storing toxins.
The vacuoles of plant cells are larger than the vacuoles of animal cells. When filled with water, the vacuole of plant cells exert pressure within the cell. This pressure is known as turgor pressure. When the vacuoles of plant cells are filled with enough water, the plant appears healthy and stands upright. When the vacuoles of plant cells do not contain enough water, then there is not enough pressure within the cell and the plant appears wilted.