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Question #47502
The Question
In the evolutionary sequence of terrestrial colonization, the symbiotic logic of fungi shifts from forming lichens (pioneer species) to establishing mycorrhizal associations (e.g., Glomus) in vascular plants. Which of the following accurately describes the systemic fallout of this evolutionary transition?
Options
- A.
The fungal role shifts from extracellular rock weathering in an undifferentiated thallus to active phosphorus mobilization within the differentiated root cortex of higher plants.
- B.
The fungal partner transitions from being the primary autotrophic component in pioneer colonization to a heterotrophic mineral scavenger in vascular plants.
- C.
The symbiotic interface evolves from intracellular haustoria in lichenized algae to strictly extracellular sheaths (ectomycorrhizae) in all advanced angiosperms.
- D.
The association shifts from providing structural anchorage via true roots in lichens to facilitating passive water absorption via rhizoids in vascular plants.
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
Differentiation vs Dedifferentiation|Lichen Symbiotic Logic|Thallus formation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize 'fungi help in absorption' without distinguishing the evolutionary and structural context (bare rock weathering in a thallus vs. soil nutrient extraction in a root cortex).
The question tests the ability to synthesize ecological succession (lichens as pioneers) with plant anatomy and microbe functionality (Glomus absorbing phosphorus).
The distractors rely on confusing autotrophic/heterotrophic roles (Option B) and the anatomical timeline of true roots vs. rhizoids (Option D).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biological Classification - Class 11 |
| Concept | Lichen Symbiotic Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |