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Question #47453
The Question
A patient presents with chronic fasting hypoglycemia. Endocrine assays reveal abnormally high circulating levels of Adrenocorticotropic Hormone (ACTH) and Glucagon. Despite these high levels, the adrenal cortex fails to secrete cortisol, and the liver fails to initiate glycogenolysis. However, exogenous administration of cortisol successfully restores normal blood glucose levels, whereas exogenous glucagon has no effect. Based on the principles of hormone action and metabolic integration, which of the following is the most accurate conclusion?
Options
- A.
The patient possesses a mutation in the intracellular receptors of both the adrenal cortex and hepatocytes, preventing hormone-receptor complex formation.
- B.
The primary defect lies in the membrane-bound receptor signaling cascade, specifically the failure to generate secondary messengers like cAMP.
- C.
The hypoglycemia is a direct result of the hypothalamic-hypophyseal portal system failing to transport Corticotropin-Releasing Hormone (CRH).
- D.
The elevated ACTH and Glucagon levels indicate a hyperactive negative feedback loop driven by excessive gluconeogenesis in the liver.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
cAMP|Protein_Kinase|Hormone-Receptor_Interaction
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between the mechanisms of action of peptide hormones (membrane-bound receptors/secondary messengers) and steroid hormones (intracellular receptors/gene expression).
Students often memorize hormone functions (like Glucagon raising blood sugar) but fail to link them to their specific signal transduction pathways.
The trap in Option A relies on confusing the receptor location for ACTH/Glucagon with that of Cortisol, while Option C tests the understanding of the hypothalamic-pituitary axis feedback loop.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Neural Control and Coordination - Class 11 |
| Concept | Hypothalamic-Pituitary Axis Integration |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |