Final answer:
Anabolic reactions are endergonic, building complex molecules and consuming energy, while catabolic reactions are exergonic, breaking down complex molecules to release energy.
Step-by-step explanation:
Relationship Among Metabolic Reactions
In biology, anabolic reactions refer to the synthesis of complex molecules from simpler ones, consuming energy in the process. These are endergonic reactions, as they require an input of energy. In contrast, catabolic reactions involve the breakdown of complex molecules into simpler ones, releasing energy, and thus are exergonic reactions. Metabolism encompasses both anabolic and catabolic processes within biological systems.
Identifying the nature of specific reactions:
- A. Cellular respiration is catabolic and exergonic because it involves the breakdown of glucose to release energy.
- B. Photosynthesis is anabolic and endergonic as it involves the creation of glucose from carbon dioxide and water using energy from sunlight.
- C. Catabolic reactions are, by definition, exergonic.
- D. Anabolic reactions are, by definition, endergonic.
In a metabolic pathway, anabolic and catabolic reactions are interconnected; anabolic reactions build up molecules using the energy that is released by catabolic reactions.