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Question #45455
The Question
A patient with a hypersecreting tumor of the adrenal medulla exhibits severe hypertension and significantly elevated levels of Atrial Natriuretic Factor (ANF). Despite the high ANF, blood analysis shows persistent sodium retention and elevated aldosterone levels. Which of the following physiological crosstalk mechanisms best explains the failure of ANF to inhibit aldosterone synthesis in this patient?
Options
- A.
Catecholamines directly downregulate ANF receptors in the zona glomerulosa, preventing signal transduction.
- B.
The sympathetic surge from the medulla stimulates juxtaglomerular cells to release renin, creating a RAAS drive that overrides ANF's inhibition.
- C.
ANF requires the permissive action of cortisol to inhibit aldosterone, which is suppressed during adrenal medulla hypersecretion.
- D.
The catecholamine surge shifts blood flow away from the adrenal cortex, preventing ANF from reaching the zona glomerulosa.
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
Hormone Receptors Location|Adrenal Cortex vs Medulla|ANF
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often view hormonal antagonism (ANF vs RAAS) as absolute.
The trap lies in failing to recognize that a pathological upstream drive (sympathetic stimulation of JG cells by the adrenal medulla) can outcompete and override the downstream inhibitory signal (ANF on the zona glomerulosa).
This tests the integration of Excretory System regulation (Chapter 19) with Endocrine System pathology (Chapter 22).
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 |