_____ is the outermost layer of alimentary canal and is made up of a thin_____.

Answer

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks for the outermost layer of the alimentary canal. The alimentary canal is the entire digestive tract, which includes various organs.

2. **Recall the Layers of the Alimentary Canal**: The walls of the alimentary canal consist of four layers:
- Mucosa
- Submucosa
- Muscularis
- Serosa (or cirrhosa)

3. **Determine the Outermost Layer**: Among these layers, the outermost layer is the serosa, which is also referred to as cirrhosa.

4. **Identify the Composition**: The question also asks what this outermost layer is made up of. The serosa is composed of a thin layer of mesothelium, which is a type of epithelial tissue, along with connective tissue.

5. **Fill in the Blanks**: Therefore, the complete answer to the question is:
- "Serosa (or cirrhosa) is the outermost layer of the alimentary canal and is made up of a thin mesothelium and connective tissue."

**Final Answer**: Serosa (or cirrhosa) is the outermost layer of the alimentary canal and is made up of a thin mesothelium and connective tissue.

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