Answer: Quaternary/Tertiary (disulfide bonds in tertiary structure).
- A Quaternary/Tertiary (disulfide bonds in tertiary structure)
- B Primary structure, since the amino acid sequence itself is cleaved
- C Secondary structure, since the alpha-helix hydrogen bonds break
- D Primary sequence, since the peptide backbone is hydrolysed
Correct answer: A. Quaternary/Tertiary (disulfide bonds in tertiary structure)
Explanation: Disulfide bonds (covalent S-S) contribute to tertiary and quaternary structure; reducing agents cleave them.
Two amino acids join via a condensation reaction: the carboxyl -OH of one and an amine -H of the other are eliminated as water, leaving a peptide bond (-CO-NH-) linking them into a dipeptide; repeating this builds a full protein chain.
Concept context
The chemistry of life: carbohydrates, proteins, lipids, nucleic acids, enzymes, and vitamins. Understand their structures, classification, and biological functions. Highly relevant for NEET and Class 12 board exams.