Number of amino acid residues in a tetrapeptide are

Peptide bond formation;-COOH+H2N-→-H2O-CO-NH-peptide linkage;Condensation of α-amino acids involves loss of water molecules ; -OH from -COOH and -H from -NH2 lose as water;Number of peptide linkages= n-1 (n=number of amino acid residues);A tetra peptide contains four amino acid residues with three peptide linkages;