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Question #46133
The Question
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Despite possessing only a tissue level of organization, Ctenophores exhibit a highly coordinated locomotory mechanism utilizing eight external rows of ciliated comb plates. Reason (R): The presence of this complex ciliary locomotive system in basal diploblasts perfectly aligns with and supports the traditional linear 'simplicity-to-complexity' model of metazoan evolution.
In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- A.
Both (A) and (R) are true and (R) is the correct explanation of (A)
- B.
Both (A) and (R) are true but (R) is not the correct explanation of (A)
- C.
(A) is true but (R) is false
- D.
(A) is false but (R) is true
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
Ctenophora Locomotion|Adaptive Radiation Logic|Vestigial Organs Interpretation
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often conflate 'basal phylogenetic position' with 'absolute structural simplicity'.
The trap lies in assuming that because Ctenophores are taught early in the Animal Kingdom (diploblastic, tissue-level), all their traits must support a linear simplicity-to-complexity model.
Recognizing that their ciliated comb plates represent an 'evolutionary primitive complexity' is key to understanding modern phylogenetic challenges to linear evolution.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Ctenophora Locomotion |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |