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Question #45366
The Question
During human fertilization, the entry of a sperm induces a calcium ion surge within the secondary oocyte. If a specific chemical inhibitor prevents the exocytosis of cortical granules without affecting the calcium surge, which of the following statements regarding the subsequent events is INCORRECT?
Options
- A.
The zona pellucida will fail to undergo the structural hardening required for the slow block to polyspermy.
- B.
Additional spermatozoa will continue to successfully bind to the ZP3 receptors present on the zona pellucida.
- C.
The resulting zygote will likely exhibit aneuploidy, leading to mitotic spindle disruption and early embryonic lethality.
- D.
The secondary oocyte will successfully complete meiosis II and extrude the second polar body.
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
Acrosin|Cortical Reaction|Zona Pellucida Hardening
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between the specific chromosomal consequences of polyspermy (Polyploidy) versus segregation errors (Aneuploidy).
Students often conflate these terms.
Additionally, it tests the nuanced understanding that the calcium surge has dual, independent roles: triggering Meiosis II completion and initiating the cortical reaction.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Acrosomal Enzyme Activation |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |