Define Amino Acids in the Building Blocks of Proteins?

Amino acids, as you have already illustrated, have a carboxyl group and an amino group bonded to a common carbon atom and differ from each other in their side chains or R groups. The R groups vary in structure, size and electric charge which influence the solubility of amino acids in water. The amino acids are joined together by specific covalent bonds called peptide bonds. All amino acids except glycine have a chiral centre and are optically active and have two possible stereoisomers called enantiomers.