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Question #47455
The Question
The Hypothalamic-Pituitary-Thyroid (HPT) axis integrates environmental temperature data to regulate Basal Metabolic Rate (BMR). In the context of Allen's Rule and thermoregulation, which of the following statements is INCORRECT regarding a tropical mammal (possessing a high surface-area-to-volume ratio) that is chronically exposed to a severe cold environment?
Options
- A.
The hypothalamus perceives chronic cold stress and persistently secretes TRH, leading to elevated thyroxine levels and increased chemical thermogenesis.
- B.
The organism's high surface-area-to-volume ratio facilitates rapid heat dissipation, forcing a continuous reliance on the HPT axis to maintain core body temperature.
- C.
To prevent metabolic exhaustion from continuous heat loss, the hypothalamus resets its homeostatic set-point and downregulates TSH secretion to conserve cellular energy reserves.
- D.
The evolutionary mismatch between its morphological heat-retention capacity and the environmental demand leads to rapid depletion of glycogen and fat reserves.
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
Hypothalamus|Thyrotropin-Releasing_Hormone|TSH
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The conflict between morphological adaptation (Allen's Rule) and physiological homeostasis.
Students often fall for the 'teleological trap'—assuming the body will smartly 'shut down' the HPT axis to save energy.
In reality, homeotherms are obligate regulators; the hypothalamus will relentlessly drive the HPT axis to maintain core temperature, causing fatal metabolic exhaustion when morphology fails to retain that heat.
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 |