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Question #45240
The Question
Which of the following statements is INCORRECT regarding the post-translational maturation and structural stability of human insulin?
Options
- A.
The excision of the C-peptide from proinsulin is a post-translational modification that occurs during its packaging within the secretory vesicles of pancreatic -cells.
- B.
The mature, biologically active insulin molecule is stabilized by three interchain disulfide bridges that covalently link the A and B polypeptides.
- C.
Exposure of mature insulin to strong reducing agents disrupts its covalent disulfide bonds, leading to the loss of its specific receptor-binding conformation.
- D.
In the recombinant DNA technique utilized by Eli Lilly, the A and B chains were synthesized independently in E. coli and later combined by creating disulfide bonds in vitro.
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
Insulin_Chain_Maturation|Protein_Denaturation_Specificity|Proinsulin
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating NCERT text with NCERT diagrams.
While the Biotechnology chapter text states chains A and B are 'linked together by disulphide bridges,' Figure 12.3 visually illustrates two interchain bonds and one intrachain bond.
Students often memorize the number '3' for total disulfide bonds in insulin but fail to distinguish between 'interchain' (between A and B) and 'intrachain' (within A), falling for this classic quantitative/structural trap.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biomolecules - Class 11 |
| Concept | Protein Denaturation Specificity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |