Simple epithelium (consists of single layer) functions as a lining for

Options

A. Body cavity
B. Ducts
C. Tubes
D. All

Answer

### Step-by-Step Solution:

1. **Understanding Simple Epithelium**:
- Simple epithelium is characterized by a single layer of cells. This structure allows for efficient functions such as absorption, secretion, and filtration.

2. **Types of Simple Epithelium**:
- Simple epithelium can be classified into three main types based on cell shape:
- **Squamous Epithelium**: Composed of flattened cells, found in areas where diffusion or filtration occurs, such as the walls of blood vessels and air sacs (alveoli).
- **Cuboidal Epithelium**: Composed of cube-shaped cells, primarily involved in secretion and absorption, found in glandular ducts and kidney tubules.
- **Columnar Epithelium**: Composed of tall, column-like cells, typically involved in absorption and secretion, found in the lining of the stomach and intestines.

3. **Functions of Simple Epithelium**:
- The primary functions of simple epithelium include:
- Lining body cavities (providing a smooth surface).
- Lining ducts (facilitating the movement of substances).
- Lining tubes (allowing for transport and exchange of materials).

4. **Conclusion**:
- Therefore, simple epithelium functions as a lining for various structures in the body, including body cavities, ducts, and tubes.

### Final Answer:
Simple epithelium functions as a lining for body cavities, ducts, and tubes.

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