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The contractile vacuole allows free-living protists to expel extra water. <b>The contractile vacuole allows free-living protists to expel extra water <br /></b>.
A vacuole is a cell organelle found in a number of different cell types. Vacuoles are fluid-filled, enclosed structures that are separated from the cytoplasm by a single membrane.They are found mostly in plant cells and fungi. However, some protist, animal cells, and bacteria also contain vacuoles.acuoles are fluid-filled, enclosed structures that are separated from the cytoplasm by a single membrane. They are found mostly in plant cells and fungi. However, some protist, animal cells, and bacteria also contain vacuoles.