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Question #46727
The Question
Thermogenin (UCP1) is a specialized protein in brown adipose tissue that increases the permeability of the inner mitochondrial membrane to protons. If actively respiring mitochondria are exposed to such an uncoupling agent, all of the following physiological events will occur, EXCEPT:
Options
- A.
A significant decrease in the rate of oxygen reduction at the cytochrome c oxidase complex.
- B.
Dissipation of the proton motive force as thermal energy instead of driving phosphorylation.
- C.
Unabated transfer of electrons from NADH + H+ through the electron transport system.
- D.
Failure of the F1 peripheral membrane protein to undergo conformational changes for ATP synthesis.
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
Plasma_Membrane_Fluidity|Inner_Mitochondrial_Membrane|Uncoupling_Agents
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse ETS 'inhibitors' (which halt both electron flow and oxygen consumption) with 'uncouplers'.
Uncouplers destroy the proton gradient but allow the ETS to run at maximum capacity.
The trap relies on the misconception that a halt in ATP production must logically result in a decrease in oxygen consumption, failing to recognize the thermodynamic decoupling.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell – The Unit of Life - Class 11 |
| Concept | Plasma Membrane Fluidity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |