As Amoeba is unicellular in nature, all functions are carried out by a single cell. When Amoeba ingests food through phagocytosis or pinocytosis then it makes a vacuole around the food particle. The vacuole in Amoeba is contractile in nature. This contractibility is important to accommodate food of various sizes and to have enough digestive enzymes. The contractile vacuole helps in maintaining the tonicity of the cell.