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Question #45308
The Question
A population of Commelina benghalensis is growing in a soil ecosystem where the process of mineralization has been severely inhibited due to the prolonged application of broad-spectrum soil microbicides. Based on the principles of resource allocation, how will this specific ecological limitation most likely alter the plant's reproductive strategy?
Options
- A.
It will increase the ratio of chasmogamous to cleistogamous flowers to promote xenogamy, thereby enhancing genetic vigor to survive the nutrient stress.
- B.
It will preferentially develop cleistogamous flowers to minimize the metabolic cost of floral displays, conserving limited nitrogen and phosphorus for assured seed set.
- C.
It will delay the transition from the vegetative to the reproductive phase indefinitely until soil detritivores restore the fragmentation and humification processes.
- D.
It will abort cleistogamous buds because continuous autogamy leads to inbreeding depression, which is highly lethal under severe mineral deficiency.
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
Cleistogamy vs Chasmogamy|Humification vs Mineralization|Endosperm Development Sequencing
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the heuristic that 'environmental stress induces sexual reproduction to create genetic variation' (which is true for many algae/fungi) and might incorrectly select Option A (chasmogamy).
The trap lies in failing to integrate Ecosystem concepts (Mineralization/Nutrient cycling) with Plant Reproduction.
The student must recognize cleistogamy not merely as an obligate autogamy mechanism, but as a highly evolved, energy-saving phenotypic response to nutrient limitation.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Sexual Reproduction in Flowering Plants - Class 12 |
| Concept | Cleistogamy vs Chasmogamy |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |