Collagen fibres are secreted by

Options

A. Mast cells
B. Macrophage
C. Histiocytes
D. Fibroblasts

Answer

**Step-by-Step Solution:**

1. **Understanding Collagen Fibers**: Collagen fibers are essential components of the extracellular matrix in animals. They provide structural support and strength to tissues and are crucial for resisting tensile forces.

2. **Identifying the Source of Collagen**: The question asks which type of cell secretes collagen fibers. The options provided are:
- A) Mast cells
- B) Macrophages
- C) Pesticides (which is likely a typo or error, as pesticides are not cells)
- D) Fibroblasts

3. **Analyzing Each Option**:
- **Mast Cells**: These cells are involved in inflammatory responses and release histamines but do not secrete collagen.
- **Macrophages**: These are phagocytic cells that play a role in immune response and do not primarily secrete collagen.
- **Pesticides**: This option is irrelevant as pesticides are chemical substances and not cells.
- **Fibroblasts**: These are specialized cells that synthesize collagen and other extracellular matrix components. They secrete collagen in the form of pro-collagen, which is then processed outside the cell to form mature collagen fibers.

4. **Conclusion**: The correct answer is **D) Fibroblasts**. They are responsible for the secretion of collagen fibers in the extracellular matrix.

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