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Question #45449
The Question
During parturition, the neuroendocrine reflex relies on a continuous positive feedback loop between uterine contractions and oxytocin secretion. If a pharmacological agent specifically dampens the /DAG secondary messenger cascade in the myometrial cells at the onset of labor, which of the following will be the most likely physiological outcome?
Options
- A.
The fetal ejection reflex will fail to trigger the initial release of fetal oxytocin, completely halting the parturition process.
- B.
The maternal hypothalamus will cease oxytocin synthesis due to the absence of direct chemical stimulation from the placenta.
- C.
Uterine contractions will fail to reach the threshold required to stimulate cervical mechanoreceptors, thereby breaking the positive feedback amplification of maternal oxytocin.
- D.
The estrogen to progesterone ratio will prematurely reverse, causing the myometrial oxytocin receptors to undergo rapid downregulation.
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
Oxytocin|Myometrium|Parturition_Neuroendocrine_Reflex
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Understanding the interdependent, cyclical nature of the Ferguson reflex.
Students often view oxytocin release as a one-way street (Hormone -> Contraction).
This question tests the realization that the mechanical contraction itself (mediated by the /DAG pathway) is the mandatory afferent trigger for subsequent maternal oxytocin surges.
It also utilizes a classic 'Functional Confusion' trap in Option A by swapping 'maternal' with 'fetal' oxytocin.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Chemical Coordination and Integration - Class 11 |
| Concept | Secondary Messenger Cascade |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |