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Question #45475
The Question
A male patient presents with testicular hyperplasia and uncontrolled proliferation of spermatogonia. Blood tests reveal normal physiological titers of GnRH, FSH, LH, and Testosterone. A biopsy reveals a loss-of-function mutation in the gene encoding an intracellular proteolytic enzyme (part of the ubiquitin-proteasome system) specifically within the Sertoli cells. Based on the principles of cellular signaling and hormone action, which of the following is the most scientifically accurate mechanism explaining this localized hyper-stimulation?
Options
- A.
Failure to degrade intracellular signaling proteins downstream of the FSH receptor extends their half-life, causing continuous stimulation of spermatogenesis despite normal FSH levels.
- B.
The mutation prevents the degradation of circulating FSH in the seminiferous tubules, increasing its localized half-life and over-stimulating Leydig cells.
- C.
The defective enzyme fails to cleave the precursor of Androgen Binding Protein (ABP), leading to an infinite accumulation of active ABP and toxic testosterone levels.
- D.
The mutation inhibits the proteolytic cleavage required for the release of Inhibin, abolishing negative feedback and causing localized FSH hyper-secretion.
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
ADA Deficiency Genetic Correction|Hormone Half-life Logic|Sertoli Cell Functions
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often assume that hyper-stimulation must be caused by elevated hormone levels (ligand excess).
This question pivots on the concept of 'intracellular signal termination'.
If the degradation machinery fails, the signal persists indefinitely even with normal hormone levels.
It also heavily tests the classic NCERT functional distinction between FSH/Sertoli cells and LH/Leydig cells, using it as a trap in Option B.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Chemical Coordination and Integration - Class 11 |
| Concept | Hormone Half-life Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |