Harversian system is characteristic of

Options

A. All bones
B. Reptilian bones
C. Mammalian bones
D. Avian bones .

Answer

**Step-by-Step Solution:**

1. **Understanding Bone Types**: Bones in mammals can be classified into two main types: compact bones and spongy bones. Compact bones are dense and have fewer spaces, while spongy bones have larger spaces.

2. **Identifying Compact Bone Structure**: Compact bones are characterized by their structural unit called the osteon, also known as the Haversian system. This system includes a central canal surrounded by concentric rings of bone matrix.

3. **Function of Haversian System**: The Haversian system is crucial for the supply of blood and nutrients to the bone tissue. The central canal contains blood vessels and nerves, which are essential for the maintenance of bone health.

4. **Determining the Correct Answer**: Since the Haversian system is specifically associated with compact bone structure and is a characteristic feature of mammalian bones, the correct answer to the question is "mammalian bones."

5. **Conclusion**: Therefore, the Haversian system is characteristic of mammalian bones.

**Final Answer**: Mammalian bones.

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