Proteins and polypeptides are formed by the condensation of α-amino acids. The correct representation of the dipeptide, glycyl alanine is

Proteins, polypeptides, oligopeptides are written from N-terminal to C-terminal of amino acid residues.∴Glycyl alanine means-COOH group of glycine must condense with -NH2 group of alanine so that the -NH2 group of glycine will be free and it will be present on left hand terminal.H2N−CH2−COOHGlycine+H2N−CH CH3|   -COOHAlanine→H2OH2N−CH2−CO∥−NH−CHCH3|   −COOHGlycyl  alanine