The term metabolic process refers to the chemical reactions that take place within living organisms to sustain their lives. Synonyms for this term include metabolic pathway, biochemical pathway, cellular respiration, and catabolism. A metabolic pathway is a series of chemical reactions that occur within the cell to produce energy or to synthesize complex molecules. Biochemical pathways refer to the chemical reactions that take place within cells and involve the production or breakdown of compounds. Cellular respiration describes the process by which cells convert glucose into energy, while catabolism refers to the breakdown of complex molecules into simpler ones. All of these terms describe the same fundamental processes that occur within living organisms to maintain life.