The vacuole is a membrane-bound organelle that is found in plant and animal cells. Vacuoles are responsible for storing a variety of materials, including water, salts, sugars, proteins, and waste products. Vacuoles also help to maintain the cell's turgor, which is the pressure that keeps the cell from collapsing. In plant cells, vacuoles also play a role in photosynthesis by storing carbon dioxide and releasing it as needed. In animal cells, vacuoles are involved in the process of digestion by storing food and digestive enzymes.