Which type of metabolism builds complex molecules from simpler ones?

• A. Anabolic metabolism
• B. Catabolic metabolism
• C. Endergonic metabolism
• D. Exergonic metabolism

Answer: (A)

Anabolic metabolism refers to the process that constructs complex molecules from simpler ones. This process is crucial for growth, repair, and the synthesis of important substances such as proteins, nucleic acids, and lipids. During anabolic reactions, energy is typically consumed, which is why these processes are often linked with energy storage and the building of cellular structures.

In contrast, catabolic metabolism breaks down complex molecules into simpler ones, releasing energy in the process. Understanding the distinction between these two types of metabolism is fundamental to grasping the overall functioning of biological systems, as they are interconnected. For instance, the energy released during catabolic reactions can be used to fuel anabolic processes.

Endergonic and exergonic reactions describe the flow of energy in metabolic processes; endergonic reactions require an input of energy, whereas exergonic reactions release energy. While these terms are related to the energy changes associated with metabolic pathways, they do not specifically define the building of complex molecules. Thus, anabolic metabolism is the correct term for the process that creates complex biological macromolecules from simpler units.