What is the term for the chemical processes that occur in the body to sustain life?

• A. Homeostasis
• B. Metabolism
• C. Osmosis
• D. Immunity

Answer: (B)

Metabolism is the set of all chemical reactions that sustain life. It covers how the body breaks down nutrients to release energy and how that energy, along with simple building blocks, is used to synthesize the molecules needed for growth, repair, and maintenance. This includes not only energy production through pathways like glycolysis and the citric acid cycle but also the construction of proteins, nucleic acids, lipids, and other essential biomolecules. In short, metabolism encompasses the entire web of chemical processes that keep cells alive and functioning.

Other terms refer to more specific ideas: homeostasis is about keeping internal conditions stable, osmosis is the movement of water across membranes, and immunity is the system that fights infections.