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Question #46530
The Question
In the autoimmune pathogenesis of Type 1 Diabetes mellitus, autoreactive T-cells often target neoantigens generated during the biochemical processing of hormones in pancreatic beta-cells. If the immune system specifically targets the polypeptide stretch that is removed to make the hormone biologically active, which of the following statements is structurally and physiologically correct regarding this target?
Options
- A.
It is the C-peptide, which is excised during maturation and is absent in the mature insulin composed only of disulfide-linked A and B chains.
- B.
It is the C-peptide, which connects the A and B chains in proinsulin and is proteolytically cleaved in the rough endoplasmic reticulum.
- C.
It is the A-chain, which is excised to allow the B and C chains to form the functional hormone via disulfide bridges.
- D.
It is the C-peptide, which remains attached to the B-chain via hydrogen bonds to maintain the structural integrity of circulating insulin.
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
C-peptide|Proinsulin|Beta_Cells
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating the structural details of insulin maturation (Biotechnology chapter) with the concept of Autoimmunity (Human Health chapter).
The trap relies on Location Specificity (RER vs.
Secretory Vesicles) and Structural Nuance (Disulfide bonds vs.
Hydrogen bonds; A/B chains vs.
B/C chains).
Students often fail to realize that cleavage occurs post-RER in the secretory pathway.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Health and Disease - Class 12 |
| Concept | Autoimmunity Principles |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |