This is the region of a long bone that articulates with other bones.

Options

A. Diaphysis
B. Epiphysis
C. Metaphysis
D. Periosteum

Answer

To answer the question "This is the region of a long bone that articulates with other bones," we need to analyze the options provided: diaphysis, epiphysis, metaphysis, and periosteum.

### Step-by-Step Solution:

1. **Understand the Structure of a Long Bone**:
- A long bone consists of several parts: the diaphysis, epiphysis, metaphysis, and periosteum. Each part has a specific function and location.

2. **Identify Each Option**:
- **Diaphysis**: This is the shaft or main section of the long bone. It is primarily made up of cortical bone and contains bone marrow and adipose tissue.
- **Epiphysis**: This is the rounded end of the long bone. It is the part that articulates (forms a joint) with other bones.
- **Metaphysis**: This is the region between the diaphysis and epiphysis. It plays a role in bone growth but is not the articulating part.
- **Periosteum**: This is a membrane that covers the outer surface of all bones. It serves as a protective layer and provides a surface for muscle attachment but does not articulate with other bones.

3. **Determine the Correct Answer**:
- Since the question specifically asks for the region that articulates with other bones, the correct answer is **epiphysis**. This part of the bone is designed to connect with other bones at joints.

4. **Conclusion**:
- The region of a long bone that articulates with other bones is the **epiphysis**.

### Final Answer:
The correct option is **epiphysis**.

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