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Question #47602
The Question
2,4-Dinitrophenol (DNP) is a chemical uncoupler that renders the inner mitochondrial membrane highly permeable to protons. If DNP is introduced into a suspension of actively respiring plant mitochondria, which of the following physiological events will NOT occur?
Options
- A.
Rapid dissipation of the proton motive force across the inner mitochondrial membrane.
- B.
Cessation of electron transport through the cytochrome complexes to molecular oxygen.
- C.
Increased consumption of molecular oxygen acting as the terminal electron acceptor.
- D.
Release of energy as heat instead of being conserved in the high-energy bonds of ATP.
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
TCA Cycle Stoichiometry|Inner Mitochondrial Membrane|2,4-Dinitrophenol
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently conflate the Electron Transport Chain (ETC) with ATP synthesis, assuming that if ATP production halts, the ETC must have also stopped.
The trap relies on failing to distinguish between an 'inhibitor' (which stops the ETC, like Cyanide) and an 'uncoupler' (which disconnects the ETC from ATP synthase).
Uncouplers allow the ETC to run continuously and even faster, but without generating ATP.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Chemiosmotic ATP Synthesis Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |