Correct Option: C

Metabolism is the sum total of chemical reactions occurring in cells. It includes both anabolism, the synthesis of the biomolecules (e.g., protein synthesis, DNA replication, glucose synthesis in plants) and catabolism, the degradation of molecules usually for the production of energy (e.g., glycolysis, Krebs Cycle). Metabolism is carried out by specific enzymes which catalyze each step of a long series of reactions.