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Question #45476
The Question
An alien weed species invades a terrestrial ecosystem. Subsequently, the native apex predator population exhibits severe reproductive collapse. Endocrine profiling of the predators reveals abnormally low levels of gonadotropins (FSH and LH), alongside high systemic concentrations of a plant-derived secondary metabolite that structurally mimics endogenous estrogen. Which of the following best explains the physiological mechanism behind this reproductive failure?
Options
- A.
The metabolite acts as a water-soluble hormone, binding to ovarian membrane receptors and triggering a rapid cAMP cascade that exhausts the gonads.
- B.
The metabolite evades hepatic degradation and conjugation pathways, resulting in an extended biological half-life that exerts continuous negative feedback on the hypothalamus.
- C.
The metabolite competitively binds to ovarian follicles, preventing endogenous estrogen from inducing the LH surge required for ovulation.
- D.
The metabolite undergoes biomagnification and selectively destroys the cytochrome P450 enzymes in the adrenal cortex, halting all steroidogenesis.
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
Hormone Half-life Logic|Alien Species Invasion Impacts|Trophic Efficiency Limits
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often understand 'negative feedback' but fail to integrate 'hormone clearance/half-life' as a critical regulator of endocrine equilibrium.
A common misconception is assuming that all hormone mimics act as receptor antagonists (blockers).
In reality, many act as hyper-potent agonists simply because they evade normal metabolic degradation, turning a normal physiological feedback loop into a pathological suppression.
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 |