Final answer:
An anabolic reaction usually requires energy. Anabolic reactions involve the building of larger molecules from smaller ones and require the input of energy.
Step-by-step explanation:
An anabolic reaction usually requires energy. Anabolic reactions involve the building of larger molecules from smaller ones and require the input of energy. Examples of anabolic reactions include the formation of proteins from amino acids and the synthesis of nucleic acids from nucleotides.