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Question #45267
The Question
A mutation in a primary spermatocyte completely inhibits the synthesis of the structural proteins required for synaptonemal complex assembly. Which of the following represents the most accurate sequence of consequences during meiosis?
Options
- A.
Recombination nodules form normally during pachytene, but the absence of the complex prevents chiasmata terminalization, leading to polyploidy.
- B.
Bivalent formation fails during zygotene, preventing crossing over and leading to random segregation of homologous chromosomes at Anaphase I, resulting in aneuploidy.
- C.
Synapsis occurs via alternative proteins, but the cell arrests at diplotene because there is no synaptonemal complex to dissolve.
- D.
Homologous chromosomes segregate accurately at Anaphase I, but the resulting haploid gametes exhibit zero recombination-linked genetic variation.
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
Synaptonemal Complex|Prophase I Sub-stages Sequence|Genetic Recombination
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often mistakenly believe the synaptonemal complex and crossing over are exclusively for generating genetic variation (Option D trap).
They fail to synthesize the structural necessity of chiasmata: holding homologous chromosomes together to ensure proper tension and accurate segregation during Anaphase I.
Without it, nondisjunction and aneuploidy are inevitable.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell Cycle and Cell Division - Class 11 |
| Concept | Synaptonemal Complex Assembly |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |