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Question #45390
The Question
The initiation of parturition in humans involves a complex neuroendocrine cascade triggered by the fully developed fetus and placenta. Which of the following statements regarding the shifting endocrine profile and the Ferguson reflex during this process is INCORRECT?
Options
- A.
Signals from the fully developed fetus stimulate the fetal adrenal cortex to secrete cortisol, which shifts the placental profile towards estrogen dominance.
- B.
A high estrogen-to-progesterone ratio upregulates oxytocin receptors in the myometrium, increasing its sensitivity to maternal oxytocin.
- C.
The Ferguson reflex operates via a positive feedback loop where cervical stretching directly stimulates the maternal posterior pituitary to synthesize oxytocin.
- D.
Placental estrogen stimulates the synthesis of prostaglandins, which act synergistically with oxytocin to induce vigorous myometrial contractions.
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
Oxytocin|Cortisol|Progesterone_Withdrawal|Placenta
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot & Location Trap: This question tests the student's ability to navigate advanced NCERT-Plus concepts (fetal cortisol shifting the estrogen/progesterone ratio) while hiding a fundamental NCERT trap in plain sight.
Students often focus so heavily on the complex mechanics of the Ferguson reflex that they overlook the basic anatomical fact: the posterior pituitary does not synthesize hormones; it only stores and releases hypothalamic hormones.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Human Reproduction - Class 12 |
| Concept | Placental Endocrine Profile |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |