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Question #45283
The Question
In human oogenesis, the secondary oocyte is ovulated in a state of physiological dormancy and requires a specific trigger to complete its equational division. Which of the following statements correctly identifies the molecular mechanism and timing of this event?
Options
- A.
The LH surge directly activates the Anaphase-Promoting Complex (APC), allowing the oocyte to exit Metaphase II and extrude the second polar body prior to sperm entry.
- B.
The entry of the sperm into the secondary oocyte induces the degradation of Maturation Promoting Factor (MPF), triggering the completion of Meiosis II before the fusion of pronuclei.
- C.
The fusion of male and female pronuclei (syngamy) initiates a metabolic shift that releases the oocyte from its arrest at the Diplotene stage of Prophase I.
- D.
The completion of the second meiotic division is an equal division triggered by the cortical reaction, resulting in two functional haploid ova.
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
Ovarian_Follicle_Stages|Secondary_Oocyte|Equational_Division
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between the precise timeline of 'sperm entry' versus 'syngamy' (pronuclear fusion), and mapping them to the exact stages of meiotic arrest.
A common misconception is confusing the LH surge's role (completing Meiosis I) with the sperm's role (completing Meiosis II), or assuming that the equational division is equal in oogenesis.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell Cycle and Cell Division - Class 11 |
| Concept | Equational Division Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |