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Question #45482
The Question
An invasive weed releases volatile allelochemicals that specifically denature the biochemical recognition factors deposited on the pollen exine of a native angiosperm. Consequently, the native plant's pistil fails to recognize the pollen, leading to a collapse in population recruitment despite the production of fully viable male gametes. Which of the following statements is INCORRECT regarding this phenomenon?
Options
- A.
The dynamic chemical dialogue required for compatible pollen-pistil interaction is disrupted, mimicking a self-incompatibility response.
- B.
This phenomenon acts as a post-zygotic isolating mechanism, because the fully viable male gametes are prevented from executing syngamy and triple fusion.
- C.
The ecological relationship between the invasive weed and the native angiosperm in this specific context is best described as amensalism.
- D.
The pistil rejects the pollen by either inhibiting its germination on the stigma or arresting pollen tube growth within the style.
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
Pollen Wall Chemistry|Biotic Interactions|Plant-Pollinator Co-evolution
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between pre-zygotic and post-zygotic reproductive isolation mechanisms in the context of plant embryology.
Students often fall for the trap that 'failure of viable gametes to fuse' is a post-zygotic event.
However, 'zygotic' refers to the formation of the zygote itself; any block prior to successful syngamy (including pollen-pistil incompatibility) is strictly pre-zygotic.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Sexual Reproduction in Flowering Plants - Class 12 |
| Concept | Pollen Wall Chemistry |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |