Page:A Text-book of Animal Physiology.djvu/43

 inorganic and unorganized food, also organized matter in the form of a complex organic compound known as protein, which contains nitrogen in addition to carbon, hydrogen, and oxygen. In fact, Amœba can prey upon both plants and animals, and thus use up as food protoplasm itself. The pseudopodia serve the double purpose of organs of locomotion and prehension.



This creature absorbs oxygen and evolves carbon dioxide.