The tertiary structure of a protein is held in shape by all of the following EXCEPT
Correct answer: D. peptide bonds between R groups
- A. hydrogen bonds between R groups
- B. ionic bonds between charged R groups
- C. disulphide bridges between cysteine residues
- D. peptide bonds between R groups
Explanation
Peptide bonds join the amino group of one residue to the carboxyl group of the next along the backbone, so they build the primary structure and never form between R groups. The fold itself is maintained by the weaker hydrogen, ionic and hydrophobic interactions between side chains, reinforced by the covalent disulphide bridge where two cysteines meet. That is why gentle heating or a pH change can unfold a protein without breaking it apart.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Proteins
Proteins are polymers of amino acids joined by peptide bonds, and their function depends on primary, secondary, tertiary and quaternary structure. The topic covers fibrous and globular proteins, enzymes, antibodies, hormones and transport proteins, as well as denaturation by heat or extreme pH.
Practise Biological Molecules
1,790 free Biological Molecules MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Biology questions like this
Biology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.