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Question #45453
The Question
A patient who recently underwent an organ transplant is prescribed an immunosuppressive agent derived from the fungus Trichoderma polysporum. Months later, the patient presents with severe systemic hypertension. Blood tests reveal abnormally high levels of Atrial Natriuretic Factor (ANF). Which of the following best explains why the elevated ANF fails to restore normal cardiovascular homeostasis in this specific clinical scenario?
Options
- A.
The immunosuppressant induces afferent arteriolar vasoconstriction and renal fibrosis, blunting the target organ's responsiveness to ANF-mediated vasodilation.
- B.
The immunosuppressant competitively binds to ANF receptors on the adrenal cortex, preventing the normal ANF-mediated inhibition of aldosterone secretion.
- C.
High levels of ANF in the presence of the immunosuppressant trigger a positive feedback loop, stimulating the Juxtaglomerular Apparatus to release more renin.
- D.
The drug directly degrades the peptide bonds of ANF in the systemic circulation, reducing its effective half-life before it reaches the renal target sites.
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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
ANF|Cyclosporin A|Juxtaglomerular Apparatus
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating two distinct NCERT facts (Cyclosporin A from Microbes in Human Welfare and ANF/RAAS regulation from Excretory Products) into a single clinical pathophysiology model.
The trap relies on the 'loss of target sensitivity' concept.
Students often assume that if a compensatory hormone (ANF) is elevated, the drug must be directly destroying the hormone (Option D) or altering its feedback loop (Option C).
They fail to recognize that the receptor organ (kidney) itself can become structurally unresponsive due to drug-induced nephrotoxicity.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Chemical Coordination and Integration - Class 11 |
| Concept | Atrial Natriuretic Factor (ANF) |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |