A vacuole is a large, fluid-filled, membrane-bounded compartment in the cytoplasm of a plant cell or a smaller vesicle (a compartment that can involve cellular secretion, storage, or nutrient uptake) in the cytoplasm of any eukaryotic cell. In many plant cells, the vacuole can occupy 80–90% of the total cell volume. In plants, vacuoles allow individual cells to increase in size without amassing bulk that would hinder cell metabolism. The cells of some bacteria contain gas vacuoles. See also contractile vacuole.