Which of the following is characteristic of mammalian bone ?

Options

A. Collagen
B. Blood vessels
C. Lymphatic vessels
D. Haversian canals

Answer

**Step-by-Step Solution:**

1. **Understanding the Components of Bone:**
- Bones are complex structures composed of various components. In mammals, these include collagen fibers, blood vessels, lymphatic vessels, and specialized structures like Haversian canals.

2. **Analyzing Each Option:**
- **Collagen:** While collagen is a significant component of bone, it is not exclusive to mammals; it is found in many other organisms as well.
- **Blood Vessels:** Blood vessels are essential for the nourishment of tissues and are present in all types of organisms, not just mammals.
- **Lymphatic Vessels:** Similar to blood vessels, lymphatic vessels are found in various organisms and are not unique to mammalian bone.
- **Haversian Canals:** These are specific to the structure of mammalian bone. They are small canals that run through the compact bone and are involved in the organization of bone tissue.

3. **Defining Haversian Canals:**
- Haversian canals are central tubes that contain blood vessels and nerves, surrounded by concentric layers of bone matrix. They are crucial for the bone's health and function, facilitating the exchange of nutrients and waste.

4. **Conclusion:**
- Since Haversian canals are unique to mammalian bone and not found in other types of bone or cartilage, they represent the characteristic feature of mammalian bone. Therefore, the correct answer is Haversian canals.

**Final Answer:**
The characteristic feature of mammalian bone is the presence of Haversian canals.

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