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Question #46474
The Question
The human vermiform appendix and coccyx are classic examples of vestigial structures. From the perspective of metabolic cost and population genetics, which of the following statements best explains the continuous evolutionary reduction of such structures and their deviation from Hardy-Weinberg equilibrium?
Options
- A.
The metabolic tax of maintaining non-functional tissues reduces energy allocation for reproduction, lowering the relative fitness of individuals with larger structures and driving directional selection.
- B.
The lack of functional use induces targeted mutations in the alleles governing these structures, leading to a rapid decline in their frequency via genetic drift.
- C.
Vestigial organs undergo stabilizing selection because their complete elimination would disrupt pleiotropic gene networks, maintaining a constant allele frequency.
- D.
Individuals with larger vestigial structures experience a higher rate of gene flow, which dilutes the alleles responsible for their reduction in the gene pool.
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
Vestigial Organs Interpretation|Optimal Foraging Theory|Hardy-Weinberg Equilibrium Variables
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that vestigial organs are 'useless' but fail to realize they are actually 'costly'.
The common misconception is that vestigial organs disappear simply because they are 'not used' (a Lamarckian view).
The NCERT-Plus depth requires understanding the Darwinian mechanism: the metabolic cost of maintaining them creates a selective disadvantage, driving directional selection that actively shifts allele frequencies away from Hardy-Weinberg equilibrium.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Evolution - Class 12 |
| Concept | Vestigial Organs Interpretation |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |