Vacuoles are membrane-bound organelles that are found in the cytoplasm of animal and plant cells. They are involved in a variety of cellular functions, including storage, waste disposal, and homeostasis. Vacuoles can store a variety of substances, including water, salts, proteins, and carbohydrates. They can also store waste products, such as toxins and metabolic byproducts. Vacuoles help to maintain homeostasis by regulating the concentration of various substances in the cytoplasm.