Which of the following is NOT one of the seven basic life functions?

• A. Photosynthesis
• B. Ingestion
• C. Respiration
• D. Reproduction

Answer: (A)

All living things perform a set of basic life processes that keep them alive: nutrition (taking in and using food), movement, respiration (releasing energy from food), growth, excretion (getting rid of waste), sensitivity or response to the environment, and reproduction. Photosynthesis is a specific energy-making process used by plants and some microorganisms, but not all organisms can do it. Because it isn’t performed universally, it isn’t counted as one of the seven basic life processes. Ingestion, respiration, and reproduction fit as universal life functions: ingestion is part of nutrition, respiration releases energy from food, and reproduction ensures the continuation of the species.