Anabolic reactions are best described as which of the following?

• A. Builds larger molecules from smaller ones
• B. Breaks down molecules to release energy
• C. Involves genetic replication
• D. Occurs only in mitochondria

Answer: (A)

Anabolic reactions are processes that build larger, more complex molecules from smaller units, using energy. This assembly is essential for growth, repair, and the creation of biomolecules such as proteins from amino acids or polysaccharides from simple sugars. Because these reactions require energy input and result in more complex products, they contrast with catabolic reactions, which break down molecules to release energy. Saying that replication of genetic material describes anabolic activity is not as precise as recognizing that anabolic processes involve bond-making to assemble large molecules, while many anabolic steps occur outside mitochondria.