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Question #45412
The Question
A chronic disruption in the hypothalamo-hypophyseal portal system impairs the delivery of hypothalamic satiety signals, leading to severe hyperphagia, obesity, and sustained hyperglycemic stress. Over time, this metabolic dysregulation causes 'secretory fatigue' in the pancreatic islets. Which of the following is the most likely biochemical consequence observed in the patient's blood plasma?
Options
- A.
An elevated ratio of pro-insulin to mature insulin due to the exhaustion of post-translational cleavage machinery in the β-cells.
- B.
A complete absence of circulating C-peptide due to the failure of the rough endoplasmic reticulum to synthesize the A and B chains.
- C.
Increased accumulation of mature insulin characterized by intact A, B, and C chains linked by disulfide bonds.
- D.
Enhanced secretion of mature insulin directly stimulated by the accumulation of releasing hormones in the pars nervosa.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Insulin_Chain_Maturation|Pro-insulin|Portal_System
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating neuroendocrine anatomy (portal system) with molecular biology (insulin maturation).
The trap relies on students knowing that mature insulin lacks the C-peptide, but failing to deduce that β-cell exhaustion (due to upstream hypothalamic failure and resulting hyperglycemia) impairs this post-translational modification, causing immature pro-insulin to spill into the blood.
Option C is a classic definitional trap by falsely describing mature insulin as having a C chain, while Option D tests anatomical location traps (pars nervosa vs portal system).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Chemical Coordination and Integration - Class 11 |
| Concept | Hypothalamo-Hypophyseal Portal System |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |