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Question #46027
The Question
In a mature forest ecosystem, an ecologist notes that despite high Net Primary Productivity (NPP) and abundant detritus accumulation, the secondary productivity within the Detritus Food Chain (DFC) is severely bottlenecked. The energy flow fails to meet the expected 10% transfer efficiency due to substrate-level limitations. According to the principles of decomposition, which of the following factors is NOT responsible for creating this ecological bottleneck?
Options
- A.
A high proportion of lignin and chitin in the accumulated plant detritus.
- B.
Extensive humification resulting in an amorphous substance highly resistant to microbial action.
- C.
Immobilization of nutrients within the biomass of soil microbes.
- D.
A high concentration of nitrogenous compounds and water-soluble sugars in the detritus.
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
Trophic Efficiency Limits|Detritus Food Chain Dominance|Secondary Productivity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the steps of decomposition but fail to apply how the chemical composition of detritus dictates the rate of these processes.
The trap relies on the 'Not/Except' format, requiring the student to distinguish between factors that cause nutrient immobility (lignin, chitin, humification) and factors that facilitate rapid microbial catabolism (nitrogen, sugars).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Nutrient Immobility |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |