What term describes the sum of chemical and physical processes which maintain life?

The term that describes the sum of chemical and physical processes which maintain life is metabolism. Metabolism encompasses all the biochemical reactions within an organism that convert food into energy and the building blocks necessary for growth, maintenance, and repair of tissues. This includes various processes such as anabolism (the building up of substances) and catabolism (the breaking down of substances).

While homeostasis refers to the body’s ability to maintain a stable internal environment despite external changes, it is more about balance and regulation rather than the sum of processes. Respiration specifically focuses on the biochemical processes that involve the exchange of gases, primarily oxygen and carbon dioxide, which is part of metabolism but not synonymous with it. Digestion is the process of breaking down food into smaller components that can be absorbed but does not encompass the wider range of metabolic activities within the body. Therefore, metabolism is the most comprehensive term that captures the entirety of chemical and physical processes vital for sustaining life.