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Question #46765
The Question
While studying cellular motility, a researcher observes two distinct types of flagella: Type X exhibits a whip-like bending movement driven by ATP, while Type Y exhibits a 360-degree rotational movement. If the structural genes of Type Y are experimentally substituted into an organism possessing Type X, the organism fails to achieve motility. Which of the following statements correctly identifies the structures and the primary reason for this functional failure?
Options
- A.
Type X is prokaryotic (9+2 axoneme) and Type Y is eukaryotic (flagellin-based). The failure occurs because eukaryotic cells lack the proton-motive force across their plasma membrane to drive flagellin rotation.
- B.
Type X is eukaryotic (tubulin-based) and Type Y is prokaryotic (flagellin-based). The failure occurs because the prokaryotic rotary motor requires a proton gradient across the plasma membrane and specific cell envelope anchorage, which the eukaryotic architecture does not support.
- C.
Type X is eukaryotic (tubulin-based) and Type Y is prokaryotic (flagellin-based). The failure occurs because prokaryotic flagella require ATP-dependent dynein arms to generate the rotational movement, which are absent in the substituted genes.
- D.
Type X is eukaryotic (tubulin-based) and Type Y is prokaryotic (flagellin-based). The failure occurs because eukaryotic basal bodies (centrioles) will erroneously assemble the introduced flagellin into a 9+0 arrangement, preventing motility.
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
Cilia and Flagella Ultrastructure|Methanogens Metabolism|Mammalia Mammary Glands
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that both prokaryotes and eukaryotes possess flagella but fail to distinguish their fundamentally different biochemical compositions (Tubulin vs.
Flagellin), movement mechanics (Bending/Sliding vs.
Rotary), and energy sources (ATP vs.
Proton-motive force).
The primary trap (Option D) exploits the knowledge that eukaryotic basal bodies have a 9+0 arrangement, tricking the student into thinking flagellin would simply misassemble into this microtubular pattern, rather than recognizing the systemic incompatibility of the motor mechanism itself.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell – The Unit of Life - Class 11 |
| Concept | Cilia and Flagella Ultrastructure |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |