Final answer:
Metabolism includes both energy-releasing catabolic reactions and energy-consuming anabolic reactions, not just reactions that yield energy; hence, the statement is false.
Step-by-step explanation:
The statement that metabolism reflects only those reactions that yield energy is false. Metabolism is the sum of all catabolic and anabolic reactions within an organism's body. Catabolic reactions involve the breakdown of complex molecules into simpler ones, releasing energy in the process, while anabolic reactions are synthetic processes that build complex molecules from simpler ones, necessitating an input of energy. The metabolic rate of an organism measures the amount of energy used to maintain life. Enzymes play a crucial role in facilitating these biochemical reactions, which would otherwise occur too slowly at the low temperatures and concentrations inside living organisms.