How does the structure of the peptide bond make the structure of proteins relatively rigid

Answer: Peptide bonds linked polpetide chains together and this polypeptide chains contain amino acids that are linked together. The linear sequence of the polypeptide chains form proteins that are linked by peptide bonds. Peptide bond Is said to be rigid because it has double bond character. Due to the double bond character of peptide bond, the structure of protein becomes rigid.

Explanation:

Peptide bond is a covalent bond that is formed between two proteins when one molecule of the carboxyl group of a molecule reacts with the aminogroup of another molecule to release water.

Answer: because it has a double bond character due to it's resonance.

Explanation: Peptide bond is formed between C of carboxyl group of one amino acid and the N of amino group of another amino acid by releasing H2O (OH of carboxyl group and H of amino group) making dipeptide structure. More amino acids are added in this dipeptide structure and polypeptide is formed. O, N, C, H are easy to rotate on phi and psi angle makes the protein rigid and due to resonance, double bond character of peptide is shown. There is negative charge on the carbonyl oxygen and positive charge on the amide nitrogen.