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Question #46784
The Question
During severe thermal stress (heat shock), cellular proteins undergo denaturation, often triggering apoptosis due to the accumulation of misfolded chains. Which of the following accurately describes the molecular basis of this structural loss while maintaining the polymer's basic integrity?
Options
- A.
The thermal gradient cleaves the rigid C-N peptide bonds, destroying the primary structure and releasing free amino acids.
- B.
Heat disrupts the hydrogen bonds stabilizing the secondary structure, altering fixed torsional angles, while the resonance-stabilized C-N bonds remain intact.
- C.
The partial double-bond character of the C-N bond is lost due to heat, causing the polypeptide backbone to fragment into oligopeptides.
- D.
Thermal energy primarily breaks the covalent disulfide bridges, leaving the hydrogen-bonded alpha-helices and beta-sheets unaffected.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Peptide Bond Geometry|Heat Shock Thermal Gradient|Secondary Protein Structure Stabilizers
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often know that 'heat destroys protein shape' but fail to distinguish between the vulnerable non-covalent bonds (hydrogen bonds) and the highly stable, resonance-stabilized covalent peptide bonds.
The trap lies in confusing the hierarchy of protein structure (Primary vs.
Secondary/Tertiary) and the specific thermodynamic stability of the bonds that maintain them.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biomolecules - Class 11 |
| Concept | Peptide Bond Geometry |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |