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Question #45510
The Question
A female patient with hyperthyroidism frequently experiences irregular menstrual cycles characterized by a shortened luteal phase. Even though her anterior pituitary secretes adequate baseline levels of Luteinizing Hormone (LH), premature luteolysis occurs. Based on the integration of metabolic and endocrine systems, which of the following mechanisms best explains this phenomenon?
Options
- A.
Elevated thyroid hormones accelerate the hepatic clearance of progesterone and disrupt LH pulsatility, leading to premature luteolysis.
- B.
High levels of thyroxine directly exert negative feedback on the corpus luteum, inhibiting the conversion of pregnenolone to progesterone.
- C.
Hyperthyroidism downregulates LH receptors on the corpus luteum, rendering it completely insensitive to circulating gonadotropins.
- D.
Increased basal metabolic rate causes the rapid renal excretion of LH glycoproteins, preventing them from maintaining the corpus luteum.
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
Corpus Luteum|Thyroid Hormone|Progesterone|Metabolic Rate
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating two separate NCERT facts: (1) LH maintains the Corpus Luteum, and (2) Thyroid hormones regulate BMR and menstrual cycles.
Students often fail to connect that systemic metabolic rate directly impacts the half-life of steroid hormones (hepatic clearance) and the pulsatile nature of gonadotropin signaling, assuming instead a direct receptor-level inhibition (Option C) or direct enzymatic block (Option B).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Corpus Luteum Fate |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |