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Question #46164
The Question
During early mammalian embryogenesis, a severe disruption in the maternal progesterone-estrogen feedback mechanism prevents the proper invagination of the neural plate. Consequently, the embryo fails to establish a defining feature of Phylum Chordata. Which of the following correctly identifies the affected structure and its embryological origin?
Options
- A.
Dorsal hollow nerve cord; derived from the ectoderm
- B.
Notochord; derived from the mesoderm
- C.
Dorsal solid nerve cord; derived from the ectoderm
- D.
Ventral hollow nerve cord; derived from the mesoderm
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
Dorsal_hollow_nerve_cord|Progesterone/Estrogen_Feedback|Chordata
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently confuse the embryonic origins of the fundamental chordate trio (Notochord = Mesoderm; Nerve Cord = Ectoderm).
Furthermore, this question tests the classic 'Location Trap' and 'Taxonomic Trap' by mixing chordate (dorsal/hollow) and non-chordate (ventral/solid) nervous system traits with their respective germ layers, while integrating human reproductive endocrinology.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Chordata Fundamental Trio |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |