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Question #45220
The Question
If an uncoupling agent is added to an actively photosynthesizing leaf, rendering the thylakoid membrane highly permeable to protons and allowing them to bypass the CF0-CF1 complex, which of the following statements is INCORRECT regarding the subsequent physiological consequences?
Options
- A.
A. The CF1 particle fails to undergo the conformational change required to catalyze the formation of ATP.
- B.
B. The reduction and regeneration phases of the C3 cycle are rapidly starved of energy substrates.
- C.
C. The photolysis of water at the lumenal side of the thylakoid membrane immediately ceases.
- D.
D. The energy released by the downhill movement of electrons through the cytochrome b6f complex is dissipated as heat.
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
ATP_Synthase|Proton_Gradient|Chloroplast_Membrane
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the interdependence of the light reaction components.
While ATP synthesis strictly depends on the proton gradient, electron transport and water splitting (photolysis) drive the gradient, not vice versa.
Uncoupling the gradient stops ATP production but does not immediately stop the ETC or photolysis, trapping students who assume 'no ATP = no light reaction at all'.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biomolecules - Class 11 |
| Concept | Enzyme Activation Energy Lowering |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |