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Question #46167
The Question
Analyze the following statements regarding the evolutionary and developmental adaptations of the notochord and skeletal structures in Chordates. Which of the following statements is INCORRECT?
Options
- A.
In Branchiostoma, the notochord extends from the head to the tail region and persists throughout its entire life.
- B.
The loss of the notochord and post-anal tail in adult Ascidia represents retrogressive metamorphosis, an evolutionary structural reduction optimizing the organism for a sessile niche.
- C.
Analogous to the regressive skeletal adaptation in adult Urochordates, the pneumatic bones in Aves represent a structural reduction that minimizes mass to optimize metabolic efficiency for flight.
- D.
In both Urochordates and Cephalochordates, the embryonic notochord is eventually replaced by a rudimentary cartilaginous vertebral column to support adult ecological demands.
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
Urochordata|Cephalochordata|Chordata_Fundamental_Trio
Why This Question Is Tricky
Common Mistakes
The Conceptual Pivot lies in the fundamental NCERT distinction between 'Chordata' and 'Vertebrata'.
A common misconception is assuming all chordates eventually form some type of vertebral column.
The trap in Option D exploits this by falsely attributing vertebrate developmental traits (cartilaginous vertebral column) to Protochordates, while Options A, B, and C correctly synthesize NCERT facts with evolutionary metabolic trade-offs (structural reduction for niche optimization).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Urochordata vs. Cephalochordata |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |