Before You Begin
Question #45537
The Question
A hypothetical human population relies entirely on barrier contraceptive methods and Artificial Reproductive Technologies (specifically ICSI, which bypasses natural gamete interaction) for thousands of generations. Over time, the population completely loses the ability for natural sperm-egg recognition due to structural changes in the zona pellucida receptors. Which of the following evolutionary mechanisms best explains this loss of natural gametic compatibility?
Options
- A.
The genes undergo directional selection, actively eliminating the energetically costly receptor proteins.
- B.
The absence of stabilizing selection allows deleterious mutations to accumulate randomly via genetic drift.
- C.
The population experiences a genetic bottleneck, fixing recessive lethal alleles for gamete recognition.
- D.
Sympatric speciation occurs due to the artificial induction of pre-zygotic reproductive isolation.
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
Sexual_Selection|Genotype_Frequency|Hardy_Weinberg
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between 'Directional Selection' (active removal of a trait due to a disadvantage) and 'Relaxed Selection with Genetic Drift' (passive loss of a trait due to the absence of stabilizing selection).
Students often fall for the Lamarckian 'use and disuse' fallacy, falsely assuming that unused traits are actively selected against to 'save energy' (Option A), rather than degrading neutrally via genetic drift when stabilizing selection is suspended.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Reproductive Health - Class 12 |
| Concept | Barrier Method Dynamics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |