Before You Begin
Question #45853
The Question
A female patient with a 45, X0 karyotype presents with primary amenorrhea and rudimentary ovaries. Based on the principles of endocrine feedback, which of the following hormonal profiles is expected in her blood serum, and what is the correct physiological rationale?
Options
- A.
Elevated FSH and LH, low Estrogen; due to the absence of negative feedback on the hypothalamic-pituitary axis.
- B.
Decreased FSH and LH, low Estrogen; due to the failure of the anterior pituitary to stimulate the rudimentary ovaries.
- C.
Elevated FSH and LH, elevated Estrogen; due to continuous hyperstimulation of the ovaries by the anterior pituitary.
- D.
Normal FSH and LH, low Estrogen; due to the downregulation of GnRH receptors in response to gonadal dysgenesis.
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
Down/Klinefelter/Turner Syndrome Karyotypes|Placental Endocrine Profile|Insulin vs Glucagon Effects
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating genetic disorders (Turner's syndrome) with endocrine feedback mechanisms.
A common misconception is that 'defective gonads lead to defective (low) gonadotropins'.
Students must realize that the hypothalamic-pituitary axis is intact, and it is the loss of the target organ's negative feedback (estrogen) that drives FSH and LH levels up.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Principles of Inheritance and Variation - Class 12 |
| Concept | Down/Klinefelter/Turner Syndrome Karyotypes |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |