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Question #45752
The Question
In a patient with untreated Diabetes Mellitus, blood glucose levels significantly exceed the renal threshold. Which of the following accurately describes the primary physiological mechanism leading to the characteristic symptom of polyuria?
Options
- A.
Saturation of carrier proteins in the proximal convoluted tubule retains glucose in the filtrate, which acts as an osmole to restrict obligatory water reabsorption.
- B.
Hyperglycemia suppresses hypothalamic osmoreceptors, leading to decreased ADH secretion and reduced facultative water reabsorption in the collecting duct.
- C.
Excess glucose in the filtrate stimulates the active secretion of sodium into the distal convoluted tubule, disrupting the counter-current mechanism.
- D.
High tubular fluid osmolarity directly stimulates the juxtaglomerular apparatus to release renin, which increases the glomerular filtration rate and urine volume.
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
SGLT2_Transporter|Insulin_vs_Glucagon_Effects|Proximal_Convoluted_Tubule
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between osmotic diuresis (solute-driven water loss) and hormonal diuresis (ADH deficiency).
Students often confuse the mechanism of polyuria in Diabetes Mellitus (osmotic) with that of Diabetes Insipidus (ADH-related).
Furthermore, it tests the exact location of glucose reabsorption (PCT) and the concept of Transport Maximum (Tm) limiting obligatory water reabsorption.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Excretory Products and Their Elimination - Class 11 |
| Concept | Renal Threshold Concept |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |