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Question #46042
The Question
An ecologist measures the standing crop of a marine pelagic ecosystem and observes that the biomass of zooplankton and small fishes far exceeds the biomass of phytoplankton. Despite this inverted biomass pyramid, the ecosystem is thermodynamically stable and supports multiple trophic levels. Which of the following statements correctly resolves this ecological paradox?
Options
- A.
The ecological efficiency in marine ecosystems is inverted, allowing more energy to flow to higher trophic levels than is assimilated by producers.
- B.
The rapid turnover rate of phytoplankton results in a high Net Primary Productivity, compensating for their low standing crop at any given snapshot in time.
- C.
The pyramid of energy in such marine ecosystems is also inverted, which sustains the high biomass of secondary and tertiary consumers.
- D.
Phytoplankton have negligible respiratory losses, making their Gross Primary Productivity (GPP) quantitatively equal to their standing crop.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Primary Succession Facilitation|Ecological Succession Climax|Alien Species Invasion Impacts
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between 'Standing Crop' (a static snapshot of biomass) and 'Productivity' (a dynamic rate of energy/biomass flow).
Students often erroneously assume a low standing crop implies low productivity, failing to account for the high turnover rate of phytoplankton which sustains the inverted biomass pyramid without violating thermodynamic laws.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biodiversity and Conservation - Class 12 |
| Concept | Species-Area Relationship |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |