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Question #46717
The Question
In the context of prokaryotic cellular organization, both mesosomes (prominent in Gram-positive bacteria) and thylakoids (in cyanobacteria) represent membranous infoldings. Which of the following statements accurately distinguishes their functional geometry and physiological roles?
Options
- A.
Mesosomes form a sequestered lumen to maintain a proton motive force for respiration, whereas thylakoids merely increase surface area for light absorption.
- B.
While mesosomes increase the surface area for respiratory enzymes and DNA replication, thylakoids form compartmentalized lumens strictly required to establish a proton gradient for photophosphorylation.
- C.
Both mesosomes and cyanobacterial thylakoids are structurally homologous to the eukaryotic chloroplast envelope, possessing a distinct double-membrane architecture.
- D.
Thylakoids are autonomous, double-membrane bound organelles within the cyanobacterial cytoplasm, whereas mesosomes are simple extensions of the plasma membrane.
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
Prokaryotic Mesosome Geometry|Thylakoid Lumen Sequestration|Cilia and Flagella Ultrastructure
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Differentiating between simple membrane infolding for surface area expansion (mesosomes) versus the evolutionary necessity of a closed, compartmentalized lumen for establishing an electrochemical proton gradient (thylakoids).
A common misconception is treating cyanobacterial thylakoids as autonomous double-membrane organelles (like chloroplasts), forgetting the fundamental NCERT rule that prokaryotes lack membrane-bound organelles.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Cell – The Unit of Life - Class 11 |
| Concept | Prokaryotic Mesosome Geometry |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |