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Question #47383
The Question
To survive chronic hypoxia and avoid a 'metabolic bottleneck' during sustained locomotion, high-altitude mammals undergo evolutionary selection for a specific skeletal muscle profile. Which of the following statements correctly identifies the favored muscle fiber type and its corresponding structural adaptation?
Options
- A.
Red muscle fibers; characterized by high myoglobin content, numerous mitochondria, and a highly developed sarcoplasmic reticulum.
- B.
White muscle fibers; characterized by high glycogen content, fewer mitochondria, and an extensive sarcoplasmic reticulum to rapidly bypass oxygen requirements.
- C.
Red muscle fibers; characterized by an extensive capillary network, high mitochondrial density, and a relatively low amount of sarcoplasmic reticulum.
- D.
White muscle fibers; characterized by low myoglobin, high mitochondrial density, and reliance on anaerobic glycolysis to prevent lactic acid accumulation.
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
Myoglobin|Taq_Polymerase_Thermal_Stability|Oxygen_Affinity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The inverse relationship between oxidative capacity and Sarcoplasmic Reticulum (SR) density.
Students often mistakenly assume that 'highly efficient' red muscle fibers must have a highly developed SR for rapid calcium release.
However, white (fast-twitch) fibers require the extensive SR for rapid, short bursts of contraction, whereas red (slow-twitch) fibers rely on high mitochondrial density for sustained aerobic activity and have comparatively less SR.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Locomotion and Movement - Class 11 |
| Concept | Red vs. White Muscle Fibers |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |