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Question #47670
The Question
Fluoroacetate poisoning leads to the massive accumulation of a 6-carbon tricarboxylic acid in the mitochondrial matrix and subsequent glucosuria, despite the subject having normal blood glucose levels. Which of the following correctly identifies the inhibited enzyme, the type of inhibition, and the physiological basis for the observed glucosuria?
Options
- A.
Aconitase; Competitive inhibition; ATP depletion in PCT cells impairs the basolateral Na+/K+ pump, halting the secondary active transport of glucose.
- B.
Citrate synthase; Allosteric inhibition; ATP depletion in PCT cells directly impairs the primary active transport of glucose via SGLT2.
- C.
Aconitase; Non-competitive inhibition; ATP depletion in the Loop of Henle prevents counter-current multiplication, leading to glucose loss.
- D.
Isocitrate dehydrogenase; Competitive inhibition; ATP depletion in DCT cells impairs the facultative reabsorption of glucose.
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
Aconitase|Citrate|TCA Cycle
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: This question requires the synthesis of two distinct NCERT chapters: 'Respiration in Plants' (TCA cycle intermediates and enzymes) and 'Excretory Products and their Elimination' (PCT reabsorption mechanisms).
The primary trap is confusing primary vs. secondary active transport in the nephron.
Students often forget that glucose transport itself (via SGLT) does not directly use ATP (it is secondary active), but relies on the Na+ gradient created by the primary active Na+/K+ ATPase.
Furthermore, it tests the specific location of glucose reabsorption (PCT) against plausible-sounding distractors.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Respiration in Plants - Class 11 |
| Concept | TCA Cycle Stoichiometry |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |