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Question #46253
The Question
A botanist observes a flowering plant exhibiting valvate aestivation, noting that its petals just touch at the margins without overlapping, creating an open floral architecture. If this plant is Calotropis, which of the following statements best explains the evolutionary synthesis between its aestivation pattern and its primary outbreeding device?
Options
- A.
The open valvate aestivation facilitates wind pollination, which is complemented by a genetic self-incompatibility mechanism to prevent autogamy.
- B.
The open architecture accommodates diverse pollinators, while dicliny ensures strict cross-pollination by spatially separating male and female flowers.
- C.
The valvate aestivation exposes the reproductive whorls, but autogamy is prevented by herkogamy, where pollen is packaged into pollinia requiring specific insect-mediated transfer.
- D.
The valvate aestivation allows easy access to the stigma, but autogamy is prevented by dichogamy, specifically protogyny, where the stigma matures before the anthers.
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
Valvate_Aestivation|Contrivances_for_Cross_Pollination
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: This question tests the student's ability to synthesize two separate NCERT chapters (Morphology of Flowering Plants and Sexual Reproduction in Flowering Plants).
Students often memorize examples of aestivation (Calotropis = valvate) and outbreeding devices in isolation.
The trap lies in failing to understand the functional, evolutionary relationship between an open floral structure (which theoretically invites selfing) and the necessity of a physical barrier (herkogamy/pollinia) to enforce cross-pollination.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Morphology of Flowering Plants - Class 11 |
| Concept | Aestivation Patterns |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |