Which of the following statements about peptide bonds are true?
A. Peptide bonds are amide linkages.
B. Peptides are polymers of amino acids.
C. Peptide bond formation is a condensation reaction.
D. A tripeptide contains three amino acid residues.
E. Peptide bonds form from nucleophilic attack by an α-carbon atom on an electron pair of an α-amino nitrogen atom of another amino acid.