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Question #47678
The Question
During primary succession on a bare rock (xerarch succession), early vascular plants rely heavily on symbiotic associations to survive in the nutrient-poor lithosphere. If fungi of the genus Glomus fail to colonize the roots of these early seral plants in a phosphate-limited environment, which of the following represents the most immediate physiological bottleneck halting their secondary productivity?
Options
- A.
Impaired synthesis of RuBisCO due to restricted nitrogen assimilation from the soil.
- B.
Failure of cellular energy transfer mechanisms due to the inability to mobilize and absorb phosphorus.
- C.
Arrest of the electron transport chain due to the lack of iron-sulfur proteins.
- D.
Inhibition of water photolysis due to the non-availability of manganese and chloride ions.
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
Glomus|Phosphorus_Cycle|Pioneer_Species
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The question tests the synthesis of three distinct NCERT chapters: Microbes in Human Welfare (Glomus absorbs Phosphorus), Ecosystem (Phosphorus reservoir is the lithosphere and is needed for energy transfer), and Succession.
The common trap is failing to link the specific ecological role of Glomus to its exact intracellular physiological consequence (ATP bottleneck).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Microbes in Human Welfare - Class 12 |
| Concept | Mycorrhiza Nutrient Dynamics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |