the answer is A because peptide bonds form only between COOH n NH2 grps which are attached to the central carbon atom. Grps 2 and 5 are part of the R grps of the two amino acids and hence cannot be involved in peptide bonding. these grps may be a part of the tertiary and quaternary structures of polypeptides dese amino acids may be a part of.Can any1 help me with this question .... Please
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