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Question #45511
The Question
In a clinical case of early pregnancy loss, a blastocyst successfully adheres to the uterine endometrium, but a cellular defect prevents the trophoblast from differentiating into a functional syncytiotrophoblast. Which of the following represents the most direct physiological consequence of this developmental failure?
Options
- A.
The anterior pituitary will upregulate Luteinizing Hormone (LH) secretion to rescue the corpus luteum and maintain the endometrium.
- B.
Absence of human chorionic gonadotropin (hCG) secretion will lead to the rapid involution of the corpus luteum and subsequent endometrial desquamation.
- C.
The corpus luteum will continue to secrete progesterone autonomously, but the embryo will fail to receive maternal oxygen.
- D.
The inner cell mass will immediately degenerate due to the lack of human placental lactogen (hPL) secreted by the maternal decidua.
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|Syncytiotrophoblast|hCG|Implantation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often know that 'progesterone maintains pregnancy' but fail to connect the exact sequence of the embryonic-maternal signaling axis.
The trap lies in assuming the maternal pituitary (LH) or autonomous ovarian function can maintain the Corpus Luteum post-implantation, whereas it is strictly dependent on the embryonic trophoblast (syncytiotrophoblast) secreting hCG to prevent the default menstrual cycle termination.
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 |