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Question #46669
The Question
An ecologist studying a pelagic marine ecosystem observes that the standing crop of phytoplankton is 4 g/m², while the standing crop of zooplankton is 21 g/m². Despite this inverted biomass pyramid, the ecosystem remains stable and nutrient cycling is maintained. Which of the following statements is INCORRECT regarding the ecological dynamics of this system?
Options
- A.
The pyramid of energy for this ecosystem remains strictly upright because the high reproductive turnover of phytoplankton ensures continuous energy flow.
- B.
The gross primary productivity (GPP) of the phytoplankton over a given period is sufficient to support the higher trophic levels despite their low instantaneous biomass.
- C.
The inverted biomass pyramid demonstrates a natural exception to Lindeman's 10% law of energy transfer between successive trophic levels.
- D.
The rapid consumption and high replacement rate of phytoplankton decouple their instantaneous reservoir size from their total trophic output.
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
Decomposition Rate Modifiers|Stratification Efficiency|Nutrient Immobility
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently conflate 'Biomass' with 'Energy'.
The trap relies on the misconception that an inverted biomass pyramid implies an inverted energy pyramid or a violation of thermodynamic efficiency (the 10% law).
It tests the critical NCERT distinction between 'Standing Crop' (a static snapshot) and 'Productivity' (a dynamic rate over time).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Ecosystem - Class 12 |
| Concept | Decomposition Rate Modifiers |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |