Before You Begin
Question #45297
The Question
A geneticist is tracking two linked genes in a primary spermatocyte undergoing meiosis. A highly specific inhibitor completely inactivates the Anaphase-Promoting Complex (APC) exactly at the onset of Anaphase I. Which of the following statements is INCORRECT regarding the cytological and genetic consequences?
Options
- A.
Securin remains undegraded, which continuously inhibits Separase from cleaving the cohesin proteins.
- B.
The physical segregation of homologous chromosomes fails, causing the cell cycle to arrest at the Metaphase I checkpoint.
- C.
The physical exchange of genetic material between non-sister chromatids is halted, preventing the formation of recombination nodules.
- D.
The bivalents remain aligned at the equatorial plate because the resolution of chiasmata cannot be completed.
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
Chromosomal_Theory_of_Inheritance|APC|Recombination_Frequency
Why This Question Is Tricky
Common Mistakes
Process Sequence Trap & Conceptual Pivot: Students often conflate the 'manifestation' of recombination (which requires chromosomal segregation to be observed in gametes) with the 'physical event' of recombination (which occurs much earlier in Prophase I).
The trap relies on the student forgetting that crossing over is entirely independent of, and temporally precedes, the APC-mediated Anaphase checkpoint.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell Cycle and Cell Division - Class 11 |
| Concept | Anaphase Promotion Complex (APC) |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |