metabolic

Metabolism refers to the set of life-sustaining chemical reactions that occur within living organisms. The three main functions of metabolism are the conversion of energy in food into a usable form for cellular processes; the conversion of food to building blocks of macromolecules (biopolymers) such as proteins, lipids, nucleic acids, and some carbohydrates; and the excretion of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow, reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells. In a broader sense, the set of reactions occurring within the cells is called intermediary metabolism. Read more on Wikipedia