If a cell did not have a vacuole, it would be unable to carry out its usual functions and would eventually die. In plants, the vacuole plays an important role in water storage and the maintenance of structure. In animals, the vacuole is much smaller, but also performs essential functions related to protection of the cell, isolation of waste products and more. Vacuoles are also present in fungi and bacteria.
The vacuole is an organelle that is composed of a semi-permeable membrane that changes shape and size based on the needs of the cell. In a plant cell that is deprived of water, for example, the vacuole will be shriveled and small, and the plant will wilt. A plant with an abundant supply of water will have vacuoles that are turgid enough to create pressure against the cell walls, causing the plant to stand upright. When this happens, the vacuole can take up as much as 90 percent of the cell’s volume. The vacuole in both plant and animal cells also functions as a waste receptacle, keeping harmful molecules separate from the cell’s interior. In addition, it works to store organic and non-organic molecules as well as break down extremely complex molecules.