What does metabolism encompass in a living organism?

Metabolism in a living organism refers to the sum of all chemical reactions that occur to maintain life. This encompasses a wide range of processes, including anabolic reactions that build complex molecules from simpler ones (such as the synthesis of proteins, nucleic acids, and carbohydrates) and catabolic reactions that break down complex molecules into simpler ones, releasing energy in the process.

The correct answer highlights that metabolism goes beyond energy storage or waste production; it includes the myriad biochemical pathways that support growth, reproduction, repair, and response to environmental changes. By integrating both energy-yielding and energy-consuming reactions, metabolism functions as a vital framework for the overall regulation and homeostasis of the organism. Understanding this comprehensive view of metabolism is crucial for exploring how organisms interact with their environment and manage their internal processes.