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Question #47644
The Question
A pharmacological agent selectively inhibits the active transport of NaCl in the thick ascending limb of Henle's loop. Assuming the secretion of Vasopressin (ADH) from the posterior pituitary remains normal, which of the following will be the most direct physiological consequence?
Options
- A.
The medullary interstitium maintains its hyperosmolarity solely through urea recycling, allowing normal urine concentration.
- B.
The counter-current multiplier fails to establish the corticomedullary gradient, rendering ADH ineffective and producing dilute urine.
- C.
Obligatory water reabsorption in the proximal convoluted tubule (PCT) is drastically reduced, leading to severe diuresis.
- D.
The descending limb of the vasa recta actively secretes NaCl into the interstitium to compensate for the loss of the gradient.
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
Loop of Henle|Vasa Recta|Proton-Coupled Transport
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the half-truth that 'ADH causes concentrated urine' without realizing that ADH only provides the permeability (the pathway).
The actual driving force for water reabsorption is the osmotic gradient established by the Loop of Henle.
If the gradient is abolished, the presence of ADH cannot prevent diuresis.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Proton Gradient Directionality |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |