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Question #47573
The Question
Echinoderms and Chordates share a close phylogenetic relationship as deuterostomes. Which of the following statements regarding their evolutionary trajectory, symmetry, and fundamental features is INCORRECT?
Options
- A.
Adult echinoderms exhibit secondary radial symmetry, but their bilaterally symmetrical larvae indicate a shared deuterostome ancestry with chordates.
- B.
The phylogenetic proximity of Echinodermata to Chordata is evidenced by the presence of a rudimentary notochord and dorsal hollow nerve cord in their bilaterally symmetrical larval stage.
- C.
The radial symmetry of adult echinoderms is an adaptation to a benthic lifestyle, representing an ontogenetic shift rather than a primitive phylogenetic trait.
- D.
Both Echinodermata and Chordata are classified under the Bilateria clade, as the fundamental body plan of their common ancestor was bilaterally symmetrical.
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
Economic Importance Matrix|Alien Species Invasion Impacts|Pteridophytes
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse phylogenetic proximity (being deuterostomes) with the sharing of defining diagnostic characters.
The trap exploits the 'Common Half-Truth' that because Echinoderm larvae are bilaterally symmetrical and evolutionarily close to Chordates, they must possess rudimentary chordate features.
It tests the strict boundary of the Chordata Fundamental Trio while acknowledging the shared deuterostome lineage and the concept of secondary radial symmetry.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Economic Importance Matrix |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |