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Question #46187
The Question
A human neonate is diagnosed with a Ventricular Septal Defect (VSD), characterized by an incomplete interventricular septum. From an evolutionary and physiological perspective, which of the following is the most accurate deduction regarding this anomaly?
Options
- A.
It is a developmental regression to the amphibian cardiac state, resulting in a complete shift from double circulation to single circulation.
- B.
It mimics the ancestral non-crocodilian reptilian heart, causing incomplete double circulation where mixed blood is pumped out through the systemic aorta.
- C.
It represents an atavistic trait of the crocodilian heart, leading to the mixing of blood exclusively at the level of the ductus arteriosus.
- D.
It is a vestigial expression of the piscine heart, ensuring that strictly deoxygenated blood is pumped to the systemic circulation.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Reptilian Heart Anatomy|Evolutionary Chronology|Vestigial Organs Interpretation
Why This Question Is Tricky
Common Mistakes
The conceptual pivot is distinguishing the exact evolutionary checkpoints of ventricular septation.
Students often lump amphibians and reptiles together as '3-chambered'.
However, amphibians have zero ventricular septation, while non-crocodilian reptiles have partial septation.
A human VSD anatomically mirrors this specific reptilian checkpoint, testing the student's ability to link a clinical embryological failure to the NCERT concept of 'incomplete double circulation'.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Reptilian Heart Anatomy |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |