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Question #45355
The Question
In a clinical case of bilateral cryptorchidism (undescended testes), a testicular biopsy reveals normal serum testosterone levels and intact Sertoli cells, but a marked absence of spermatids. Instead, there is a significant accumulation of primary spermatocytes. Which of the following best explains the physiological basis of this specific meiotic arrest?
Options
- A.
High core body temperature induces apoptosis of Sertoli cells, halting the secretion of Androgen Binding Protein (ABP).
- B.
Thermal denaturation of heat-sensitive proteins disrupts meiotic checkpoints, preventing the progression of primary spermatocytes through Meiosis I.
- C.
Elevated temperature downregulates LH receptors on Leydig cells, causing a localized deficiency of testosterone required for spermiogenesis.
- D.
Spermatogonia fail to undergo mitotic proliferation due to the thermal inactivation of enzymes required for DNA replication.
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
Scrotal_Thermoregulation|Inhibin|Meiosis_I_Completion
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students know 'heat stops spermatogenesis' (NCERT fact) but often fail to pinpoint the exact cellular target.
The common misconception is that heat destroys the supporting cells (Sertoli/Leydig) or halts initial mitosis.
The question tests the NCERT-Plus depth that thermal stress specifically induces meiotic arrest in primary spermatocytes by disrupting heat-sensitive meiotic regulatory proteins, while somatic testicular cells remain functional.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Meiotic Arrest Points |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |