The main difference between white and yellow
fibres is of

Options

A. protein
B. colour of fibres
C. both (1) and (2)
D. none of these

Answer

To answer the question about the main difference between white and yellow fibers, we can break down the solution into the following steps:

### Step 1: Identify the Types of Fibers
- There are two main types of fibers in connective tissue: white fibers and yellow fibers.

### Step 2: Understand the Composition of White Fibers
- White fibers are primarily composed of collagen. Collagen is a protein that provides strength and toughness to the fibers.

### Step 3: Understand the Composition of Yellow Fibers
- Yellow fibers are primarily composed of elastin. Elastin is a protein that provides elasticity and flexibility to the fibers.

### Step 4: Analyze the Color of the Fibers
- White fibers are colorless and appear white and shiny due to the collagen they contain.
- Yellow fibers have a yellowish appearance due to the presence of elastin.

### Step 5: Compare the Properties of the Fibers
- White fibers are inextensible and provide tensile strength, making them tough.
- Yellow fibers are more elastic and can stretch, providing flexibility.

### Step 6: Identify the Locations of the Fibers
- White fibers are found in tendons (connecting muscle to bone) and sheaths (like the pericardium of the heart).
- Yellow fibers are found in ligaments (connecting bone to bone).

### Conclusion
- The main difference between white and yellow fibers lies in their protein composition (collagen in white fibers and elastin in yellow fibers) and their color (colorless for white fibers and yellow for yellow fibers). Therefore, both the protein and the color are key differences.

### Final Answer
- The main difference between white and yellow fibers is due to the presence of different proteins (collagen in white fibers and elastin in yellow fibers) and their respective colors.

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