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Question #47391
The Question
The deep muscles attached to the lumbar vertebrae (L1-L5) are primarily responsible for maintaining an erect posture. If a biomechanical anomaly at the lumbosacral junction increases the continuous torque on the lower back, these muscles must undergo a compensatory adaptation to prevent fatigue. Which of the following statements regarding these adapting muscles and their associated skeletal framework is INCORRECT?
Options
- A.
They will exhibit a high concentration of the oxygen-storing pigment myoglobin, giving them a reddish appearance.
- B.
They will contain plenty of mitochondria to utilize large amounts of oxygen for aerobic ATP production.
- C.
They will develop an extensive sarcoplasmic reticulum to rapidly release calcium for prolonged, sustained contractions.
- D.
The bony framework supporting these muscles in an adult human consists of 26 serially arranged vertebrae, including 5 lumbar and 1 fused sacral vertebra.
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
Vertebral Column Formula|Red vs. White Muscle Fibers
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often incorrectly assume that 'sustained, continuous contraction' (posture) requires a massive, rapid calcium release system (extensive SR).
However, NCERT explicitly distinguishes that Red (postural/aerobic) fibers have less sarcoplasmic reticulum, while White (fast/anaerobic) fibers have more SR for quick bursts.
The trap relies on confusing the inverse relationship between mitochondrial density and sarcoplasmic reticulum volume in muscle fiber types.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Locomotion and Movement - Class 11 |
| Concept | Vertebral Column Formula |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |