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Question #45437
The Question
A patient presents with severe hyperglycemia, central obesity, and immunosuppression. Hormonal profiling reveals elevated cortisol but abnormally low ACTH levels. A localized mass is identified in the adrenal cortex. Which of the following statements correctly explains the cellular and molecular basis of this pathology, distinguishing it from physiological glandular hyperplasia?
Options
- A.
The mass resulted from a mutation converting a tumor suppressor gene into a proto-oncogene in the zona fasciculata, making the cells highly dependent on ACTH.
- B.
A proto-oncogene mutation in the zona fasciculata induced autonomous cellular proliferation, and the resulting hypercortisolism caused negative feedback suppression of the HPA axis.
- C.
Chronic hypothalamic stimulation caused compensatory hyperplasia in the zona reticularis, leading to a loss of contact inhibition and subsequent ACTH suppression.
- D.
The neoplastic cells in the zona glomerulosa have lost contact inhibition, leading to uncontrolled proliferation and secondary suppression of the anterior pituitary.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Zona_Fasciculata|Adrenal_Tumors|Proto-oncogenes
Why This Question Is Tricky
Common Mistakes
The 'Conceptual Pivot' is the integration of the HPA axis negative feedback loop with the molecular basis of cancer.
Students often fail to recognize that in autonomous tumors (neoplasia driven by oncogenes), the trophic hormone (ACTH) will be suppressed due to negative feedback, whereas in physiological hyperplasia, the trophic hormone is the driving force and would be elevated.
The question also utilizes a 'Location Trap' by testing the precise anatomical origin of cortisol (zona fasciculata vs. glomerulosa/reticularis).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Chemical Coordination and Integration - Class 11 |
| Concept | Adrenal Cortex vs Medulla |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |