Which process requires energy to synthesize larger molecules?

Anabolism is the metabolic process that requires energy to synthesize larger molecules from smaller ones. During this process, simple molecules, such as amino acids and fatty acids, are built up into complex molecules like proteins and lipids, respectively. This requires energy input, often in the form of adenosine triphosphate (ATP) or other energy-rich compounds, which is essential for driving these synthetic reactions.

Anabolic processes are vital for growth, repair, and maintenance of body tissues and are involved in forming new cells, building muscle, and producing hormones and enzymes. The requirement for energy distinguishes anabolism from catabolism, which is the breakdown of larger molecules into smaller ones, releasing energy. Metabolism encompasses both anabolic and catabolic processes, while fermentation refers to a specific metabolic process for energy production, typically in anaerobic conditions, and does not primarily focus on the synthesis of larger molecules.