Epithelial cells involved in absorption of digested food have on their free surface.

Options

A. Pinocytic vesicles
B. Microvilli
C. Zymogen granules
D. Phagocytic vessicles

Answer

To answer the question, "Epithelial cells involved in absorption of digested food have on their free surface," we need to analyze the options provided and understand the role of different structures associated with epithelial cells.

### Step-by-Step Solution:

1. **Understand the Role of Epithelial Cells**: Epithelial cells line the surfaces of organs and structures throughout the body. In the context of digestion, they are primarily involved in the absorption of nutrients from digested food.

2. **Evaluate the Options**:
- **Option 1: Phagocytic Vesicles**: Phagocytosis is a process where cells engulf solid particles. While this is important for certain immune functions, it is not the primary mechanism for nutrient absorption in epithelial cells of the intestines. Therefore, this option is incorrect.

- **Option 2: Microvilli**: Microvilli are tiny, finger-like projections on the surface of epithelial cells, particularly in the intestines. They significantly increase the surface area available for absorption, making them crucial for the efficient uptake of nutrients. This option is likely correct.

- **Option 3: Zymogen Granules**: Zymogen granules are storage forms of digestive enzymes found in the pancreas. They are not directly involved in the absorption of nutrients by epithelial cells, so this option is also incorrect.

- **Option 4: Phagocytosis**: As mentioned earlier, phagocytosis pertains to the uptake of solid food particles, which is not the main function of epithelial cells in nutrient absorption. Thus, this option is incorrect as well.

3. **Conclusion**: After evaluating all options, the correct answer is **Option 2: Microvilli**. These structures enhance the absorptive capacity of epithelial cells by increasing the surface area available for nutrient uptake.

### Final Answer:
Epithelial cells involved in absorption of digested food have microvilli on their free surface.

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