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Question #46967
The Question
In a hypothetical scenario, a mutation replaces the rigid Z-lines of cardiac muscle sarcomeres with flexible, proteinaceous strips structurally analogous to the pellicle of Euglena. Which of the following would be the most direct physiological consequence of this alteration?
Options
- A.
The muscle would undergo non-linear deformation instead of generating the high-tension, synchronized shortening required for effective ventricular systole.
- B.
The thin filaments would fail to undergo cross-bridge cycling due to the masking of active sites on actin by the flexible protein strips.
- C.
The cardiac muscle would lose its functional syncytium property because the flexible strips would directly degrade the gap junctions in intercalated discs.
- D.
The sliding filament mechanism would generate excessive tension, leading to sustained tetanic contractions independent of the SA node.
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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
Euglenoid Pellicle Flexibility|Chrysophytes Silica Wall|Mycoplasma
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often focus solely on the biochemical interactions of the sliding filament theory (ATP, Calcium, Troponin) and overlook the mechanical necessity of the Z-line.
This question tests the understanding that macroscopic, high-tension linear contraction requires rigid mechanical anchoring to translate microscopic sliding into effective physiological work (ventricular systole).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Biological Classification - Class 11 |
| Concept | Euglenoid Pellicle Flexibility |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |