Anabolism is a set of metabolic pathways that construct molecules from smaller units. These reactions require energy, known as an endergonic process, and are the building-up aspect of metabolism. Anabolism is powered by catabolism, where large molecules are broken down into smaller parts and then used up in cellular respiration. Many anabolic processes are powered by the cleavage of adenosine triphosphate (ATP) . Anabolism usually involves reduction and decreases entropy, making it unfavorable without energy input. Anabolism operates with separate enzymes from catalysis, which undergo irreversible steps at some point in their pathways. This allows the cell to regulate the rate of production and prevent an infinite loop, also known as a futile cycle, from forming with catabolism.
In simpler terms, anabolism is the process by which the body utilizes the energy released by catabolism to synthesize complex molecules. These complex molecules are then used for various functions in the body, such as building muscle mass and bone development. Anabolism is the opposite of catabolism, which is the process of breaking down larger structures into smaller units.
