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Question #45915
The Question
A novel antibiotic targets Gram-negative bacteria by inserting itself into the plasma membrane and acting as a proton ionophore, allowing the free, unregulated passage of ions across the membrane. Based on the chemiosmotic hypothesis, which of the following statements correctly describes the immediate physiological impact on the bacteria?
Options
- A.
The rate of electron transport will decrease, leading to an immediate halt in oxygen consumption.
- B.
ATP synthesis by the - complex will cease despite the continuous operation of the electron transport chain.
- C.
The accumulation of protons in the periplasmic space will increase, hyperpolarizing the plasma membrane.
- D.
Substrate-level phosphorylation will become the sole source of ATP, yielding a net of 38 ATP per glucose molecule.
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
Chemiosmosis|Proton_Leakage|Flocs_Formation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently conflate the Electron Transport Chain (ETC) with Oxidative Phosphorylation.
The trap assumes that if ATP synthesis stops, the ETC and oxygen consumption must also stop.
However, membrane-disrupting agents act as 'uncouplers'—they destroy the proton gradient (the physical link), meaning the ETC continues to burn fuel and consume oxygen, but no ATP is synthesized because the particle lacks the proton motive force required for conformational change.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Respiration in Plants - Class 11 |
| Concept | Chemiosmotic ATP Yield |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |