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Question #45377
The Question
In human fertilization, the cortical reaction releases proteases that degrade ZP3 receptors on the zona pellucida, establishing a chemical block to polyspermy. Suppose a pathological condition causes the premature secretion of similar proteases into the ampullary region of the fallopian tube prior to sperm arrival. Which of the following phenomena in angiosperms is functionally most analogous to the resulting failure of fertilization?
Options
- A.
The genetic mechanism of self-incompatibility, which acts as a pre-fertilization molecular barrier preventing pollen germination.
- B.
The temporal separation of gamete maturation seen in protandry, which prevents autogamy.
- C.
The secretion of chemical attractants by the filiform apparatus to guide the pollen tube into the synergid.
- D.
The physical barrier of herkogamy, where the spatial separation of anther and stigma prevents pollen deposition.
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
Oviductal_Fluids|Acrosin|Ovum_Microenvironment
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Cross-kingdom functional analogy.
Students must connect the molecular receptor-level block in human polyspermy prevention (ZP3 degradation) with the chemical dialogue in plant self-incompatibility.
The trap lies in distinguishing a molecular/receptor-mediated barrier from temporal (protandry), spatial (herkogamy), or facilitative (filiform apparatus) mechanisms.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Polyspermy Prevention Mechanisms |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |