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Question #45741
The Question
In the regulation of kidney function, the Atrial Natriuretic Factor (ANF) acts as a physiological antagonist to the Renin-Angiotensin-Aldosterone System (RAAS). If a patient experiences chronically elevated levels of ANF due to an atrial anomaly, which of the following represents the most accurate sequence of renal and systemic consequences?
Options
- A.
Vasodilation of blood vessels, suppression of renin release from the JGA, and decreased conditional Na+ reabsorption in the distal tubules, leading to natriuresis and hypovolemia.
- B.
Direct inhibition of obligatory Na+ reabsorption in the proximal convoluted tubule (PCT), leading to massive polyuria and a compensatory spike in aldosterone secretion.
- C.
Inhibition of angiotensin II formation, leading to decreased ADH secretion and a compensatory increase in obligatory water reabsorption in the PCT.
- D.
Stimulation of the adrenal medulla to suppress aldosterone, causing decreased K+ excretion and increased Na+ retention in the collecting duct.
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
Proximal Convoluted Tubule Selectivity|ANF Antagonism|RAAS System
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between 'obligatory' reabsorption in the PCT (hormone-independent) and 'conditional' reabsorption in the DCT/CD (hormone-dependent).
A common misconception is that systemic hormones like ANF drastically alter the bulk reabsorption in the PCT.
In reality, ANF fine-tunes distal segments by antagonizing RAAS, leading to a failure of compensatory distal adjustment.
Option D also includes a classic anatomical location trap (Adrenal Medulla vs.
Adrenal Cortex).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Excretory Products and Their Elimination - Class 11 |
| Concept | Proximal Convoluted Tubule Selectivity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |