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Question #45516
The Question
Evolutionary strategies for ensuring zygote integrity and species-specific fertilization differ significantly between mammals and flowering plants. Which of the following statements regarding gamete interaction and the prevention of polyspermy is INCORRECT?
Options
- A.
In mammals, the sperm's contact with the zona pellucida induces membrane changes that physically block the entry of additional sperms.
- B.
The cortical reaction in human ova involves the exocytosis of cortical granules, leading to the hardening of the zona pellucida.
- C.
In angiosperms, the filiform apparatus undergoes structural hardening post-fertilization to act as a physical barrier against multiple pollen tubes, analogous to the zona pellucida.
- D.
Angiosperms primarily rely on a dynamic, pre-fertilization biochemical dialogue during pollen-pistil interaction to ensure species-specific compatibility.
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
Ovarian Follicle Stages|Polyspermy Prevention Mechanisms|Pollen-Pistil Interaction
Why This Question Is Tricky
Common Mistakes
The 'Conceptual Pivot' is a false evolutionary analogy.
Students often assume that since mammals utilize a post-fertilization physical barrier (zona hardening) to prevent polyspermy, angiosperms must have a direct structural equivalent.
The trap exploits the filiform apparatus, confusing its actual NCERT-defined role (pre-fertilization guidance) with a fabricated role (post-fertilization physical block).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Ovarian Follicle Stages |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |