The______epithelium is made of a single thin layer of flattened cells with irregular boundaries.

Answer

**Step-by-Step Solution:**

1. **Identify the Characteristics**: The question describes an epithelium that consists of a single thin layer of flattened cells with irregular boundaries.

2. **Recall Epithelium Types**: In biology, there are several types of epithelial tissues, including squamous, cuboidal, and columnar. We need to focus on the characteristics provided.

3. **Match Characteristics**: The description of a "single thin layer of flattened cells" aligns with the characteristics of squamous epithelium. Squamous epithelium is known for its flat, thin cells that are closely packed together.

4. **Confirm the Name**: Based on the characteristics and the definition of squamous epithelium, we can conclude that the answer to the question is "squamous".

5. **Contextual Understanding**: Squamous epithelium is commonly found in areas where diffusion or filtration occurs, such as in the alveoli of lungs, lining of blood vessels, and the mouth (buccal cavity).

**Final Answer**: The squamous epithelium is made of a single thin layer of flattened cells with irregular boundaries.

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