Amino acid 23/07/2019 Amino acids are organic molecules that are used by the body as building blocks to construct proteins. Many amino acids also have a vast range of metabolic functions where they are further modified to perform key metabolic functions in the body. Related Articles: ElectrAAte at BridgeClimb SydneyBuilding your immune system with OptimAAteMembers PageNew Roles for Red Blood CellsMaintaining muscle is crucial for well-being in elderly adults.