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Question #47515
The Question
While spermatophytes achieved extensive adaptive radiation across diverse terrestrial ecosystems via siphonogamy, bryophytes remained ecologically restricted as an evolutionary 'half-way house'. Which of the following best explains the fundamental reproductive constraint limiting the adaptive radiation of bryophytes in arid habitats?
Options
- A.
They failed to evolve a dominant sporophyte generation, making their haploid thallus highly susceptible to vegetative desiccation.
- B.
They retained zoidogamy, wherein the release of non-motile male gametes requires a water current to passively reach the archegonium.
- C.
Their reliance on zoidogamy necessitates an external water medium for the chemotactic movement of biflagellate antherozoids to the archegonium.
- D.
The absence of vascular tissues prevented the development of siphonogamy, which strictly requires xylem vessels to guide pollen tube growth.
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
Meristematic Totipotency|Cytokinin-Auxin Ratio|Bryophyte Dependence Mechanics
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the vegetative limitations of bryophytes (lack of true roots/vascular tissue) with their reproductive limitations.
The NCERT explicitly states that their limited distribution is due to the requirement of water for sexual reproduction.
The question also tests the 'Word-Play' trap in Option B by swapping 'motile/biflagellate' with 'non-motile', and the 'Functional Confusion' trap in Option D by falsely linking pollen tube growth to xylem vessels.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Bryophyte Dependence Mechanics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |