Which character is not associated with red muscle fibres ?

Options

A. High quantity of myoglobin is present
B. Amount of mitochondria are more
C. Amount of sacroplasmic reticulum is high
D. Contraction is slow and for long duration

Answer

To determine which character is not associated with red muscle fibers, we will analyze each of the given options based on the known characteristics of red muscle fibers.

### Step-by-Step Solution:

1. **Understanding Red Muscle Fibers:**
- Red muscle fibers, also known as slow-twitch fibers, are characterized by their endurance and ability to sustain prolonged activity.

2. **Analyzing the Options:**
- **Option A: High quantity of myoglobin is present.**
- Red muscle fibers contain a high amount of myoglobin, which gives them their red color and aids in oxygen storage. This statement is true.

- **Option B: Amount of mitochondria is more.**
- Red muscle fibers have a higher number of mitochondria compared to white muscle fibers. This allows them to produce energy efficiently through aerobic respiration. This statement is also true.

- **Option C: Amount of sarcoplasmic reticulum is high.**
- The sarcoplasmic reticulum in red muscle fibers is not particularly high; it is generally moderate. This statement is not true and indicates a characteristic that is not associated with red muscle fibers.

- **Option D: Contraction is slow and for long duration.**
- Red muscle fibers are known for their slow contraction speed and ability to sustain contractions over long periods. This statement is true.

3. **Conclusion:**
- The character that is not associated with red muscle fibers is **Option C: Amount of sarcoplasmic reticulum is high.**

### Final Answer:
**The character that is not associated with red muscle fibers is: Amount of sarcoplasmic reticulum is high.**

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