Haversian canals are found in

Options

A. Matrix of mammalian bone
B. Matrix of amphibian bone
C. Matrix of reptilian bone
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Haversian Canals**: Haversian canals are specialized structures found within bone tissue. They are essential for the nourishment and communication within the bone.

2. **Identifying the Location**: Haversian canals are located within the matrix of bone. The matrix is the intercellular substance that provides structural support.

3. **Types of Bones**: The question provides options related to different types of bones: mammalian, amphibian, and reptilian. We need to determine where Haversian canals are specifically found.

4. **Analyzing Bone Structure**: In mammals, particularly in compact bone, Haversian canals run longitudinally and contain blood vessels and nerves. This structure is crucial for the supply of nutrients to bone cells, known as osteocytes.

5. **Conclusion**: Haversian canals are primarily found in the matrix of mammalian bone, specifically in the compact bone structure. They are not typically found in the same form in amphibian or reptilian bones.

6. **Final Answer**: Therefore, the correct answer to the question "Haversian canals are found in" is the matrix of mammalian bone.

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