Coelom is lined by :-

Options

A. Ectoderm
B. Mesoderm
C. Endoderm
D. Mesogloea

Answer

To solve the question "Coelom is lined by:", we will analyze the options provided and understand the concept of coelom and the germ layers involved.

### Step-by-Step Solution:

1. **Understanding Coelom**:
- Coelom is defined as the body cavity found in many multicellular organisms. It is a fluid-filled space that separates the digestive tract from the outer body wall.

2. **Identifying Germ Layers**:
- In embryonic development, organisms typically have three primary germ layers:
- **Ectoderm**: The outermost layer that develops into the skin and nervous system.
- **Mesoderm**: The middle layer that forms muscles, bones, and the circulatory system.
- **Endoderm**: The innermost layer that develops into the lining of the digestive tract and some organs.

3. **Function of Coelom**:
- The coelom serves as a protective cavity for internal organs and allows for their movement and growth. It is crucial for the proper functioning of the organs housed within it.

4. **Lining of Coelom**:
- The coelom is specifically lined by the mesoderm. This layer provides the necessary support and structure to the coelomic cavity.

5. **Conclusion**:
- Based on the understanding of coelom and the germ layers, the correct answer to the question is **Mesoderm**.

### Final Answer:
Coelom is lined by **Mesoderm** (Option B).

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