Amoeba obtains its nutrition in heterotrophic mode. Both the anabolic and catabolic functions are carried out in the same cell. Amoeba feeds on plankton and diatomspresent in water. It can form arm- like structures called pseudopodia, extending from any part of its body as it is shapeless. When it senses food in its surroundings it extends its pseudopodia in that direction and moves towards it. Then it engulfs the food with its pseudopodia. When the food enters its body the amoeba forms a food vacuole around it which contains certain enzymes to digest the food. When the food is digested the unwanted waste is released through its body surface.