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Question #47617
The Question
In a terrestrial ecosystem dominated by C3 plants, high ambient temperatures and light intensities trigger a metabolic shift that impacts energy flow. Which of the following statements regarding this phenomenon is INCORRECT?
Options
- A.
The oxygenase activity of RuBisCO initiates the C2 cycle, which releases CO2 in the mitochondria while consuming ATP, thereby reducing Net Primary Productivity (NPP).
- B.
The metabolic cost of photorespiration acts as a limiting factor for the ecosystem, as NPP represents the actual biomass available for consumption by heterotrophs.
- C.
The reduction in NPP due to photosynthetic inefficiency directly decreases secondary productivity, which is defined as the rate of formation of new organic matter by decomposers.
- D.
C4 plants avoid this specific reduction in secondary productivity under similar conditions because they possess a spatial mechanism that concentrates CO2 at the RuBisCO enzyme site.
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
Energy_Flow|Photorespiration|Trophic_Levels
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot & Micro-Terminology Trap: This question places a high cognitive load on the student by integrating Plant Physiology (Photosynthesis/Photorespiration) with Ecology (Ecosystem Productivity).
Students often focus so heavily on the complex relationship between RuBisCO's oxygenase activity and NPP that they gloss over the foundational ecological definition at the end of Option C.
Confusing 'consumers' with 'decomposers' tests precise NCERT terminology retention under synthesis-level pressure.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Photosynthesis in Higher Plants - Class 11 |
| Concept | Photorespiration Metabolic Cost |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |