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Question #47586
The Question
A newly discovered thermophilic alga possesses an extreme GC-rich chloroplast genome. This extreme GC bias leads to severe translational stalling, completely preventing the synthesis of the protein scaffold of the Light Harvesting Complex (LHC). However, the biochemical synthesis of chlorophyll a and accessory pigments remains completely unaffected. If a researcher plots the absorption spectrum of the extracted pigments and the action spectrum of the intact alga, which of the following is the most likely observation?
Options
- A.
The absorption spectrum will show characteristic peaks in the blue and red regions, but the action spectrum will be severely depressed.
- B.
Both the absorption and action spectra will perfectly overlap, as the presence of chlorophyll a guarantees photosynthetic activity.
- C.
The absorption spectrum will be completely flat because pigments cannot absorb light without being bound to the LHC proteins.
- D.
The action spectrum will show normal peaks, but the absorption spectrum will shift to the green region due to the extreme GC content.
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
Action Spectrum|Absorption Spectrum|Chargaff’s Rule Limitation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Differentiating between the physical property of light absorption (Absorption Spectrum) and the biological utilization of that energy (Action Spectrum).
Students often conflate the mere presence of chlorophyll with the automatic occurrence of photosynthesis, forgetting that the Light Harvesting Complex is a 'pigment-protein' complex where the structural integrity of the protein scaffold is an absolute prerequisite for energy transfer.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Action Spectrum vs Absorption Spectrum |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |