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Question #47591
The Question
A C3 plant is subjected to acute high-temperature stress, resulting in the selective thermal denaturation of the Oxygen Evolving Complex (OEC) located on the inner side of the thylakoid membrane. Which of the following will NOT be an expected physiological consequence of this damage?
Options
- A.
Accumulation of the oxidized form of the Photosystem II reaction center (P680+) due to the cessation of electron supply.
- B.
Immediate cessation of cyclic photophosphorylation due to the disruption of electron flow from Photosystem II to Photosystem I.
- C.
A decline in the Net Primary Productivity (NPP) of the plant due to the restricted reduction of NADP+ to NADPH + H+.
- D.
A decrease in proton concentration within the thylakoid lumen, impairing chemiosmotic 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
Photolysis of Water Stoichiometry|Thermal Tolerance Ranges|Productivity Ratios
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate the entire light reaction as being strictly dependent on the photolysis of water.
The trap exploits the functional independence of cyclic photophosphorylation, which relies solely on PSI (P700) and bypasses the heat-labile OEC and PSII entirely.
It also tests the integration of Class 11 Bioenergetics with Class 12 Ecosystem productivity (NPP).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Photolysis of Water Stoichiometry |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |