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Question #46346
The Question
A patient is diagnosed with a severe impairment in the Renin-Angiotensin-Aldosterone System (RAAS) due to unresponsive mineralocorticoid receptors in the renal tubules. Despite normal hepatic synthesis of plasma proteins, the patient suffers from severe hypotension and systemic fluid redistribution failure. Which of the following best explains this physiological collapse?
Options
- A.
The inability to reabsorb and water in the distal convoluted tubule leads to profound hypovolemia, rendering normal oncotic pressure insufficient to maintain systemic blood pressure.
- B.
The absence of aldosterone hyper-stimulates the counter-current mechanism, causing excessive water retention in the vasa recta and subsequent dilution of plasma proteins.
- C.
The failure of RAAS directly inhibits the release of Atrial Natriuretic Factor (ANF), which normally acts synergistically with plasma proteins to increase blood volume.
- D.
The lack of aldosterone prevents the active secretion of in the proximal convoluted tubule, disrupting the medullary osmotic gradient required for plasma protein function.
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
RAAS_Mechanism|Tubular_Secretion_Specificity|Plasma_Proteins
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often view oncotic pressure (plasma proteins) and hydrostatic pressure (RAAS/blood volume) as independent systems.
The trap is failing to realize that oncotic pressure is functionally useless for maintaining systemic blood pressure if the absolute blood volume is critically depleted due to RAAS failure.
Additionally, Option D employs a classic 'Location Trap' by placing a correct physiological action ( secretion) in the wrong anatomical segment (PCT instead of DCT).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Body Fluids and Circulation - Class 11 |
| Concept | Plasma Proteins and Osmotic Pressure |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |