Functional unit of food absorption are

Options

A. Villi
B. Brunner's glands
C. Crypts of Lieberkuhn
D. Peyer's patches

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the functional unit of food absorption in the human body.

2. **Identifying the Site of Absorption**: Food absorption primarily occurs in the small intestine, which is the organ responsible for absorbing nutrients from digested food.

3. **Analyzing the Structure of the Small Intestine**: The lining of the small intestine has many folds. These folds are essential as they significantly increase the surface area available for absorption.

4. **Identifying Key Structures**: On these folds, there are small, finger-like projections known as villi. Villi are crucial for the absorption process because they provide a larger surface area for nutrients to be absorbed into the bloodstream.

5. **Conclusion**: Given that villi are the structures that enhance the absorption of nutrients in the small intestine, we can conclude that the functional unit of food absorption is the villi.

6. **Final Answer**: The functional unit of food absorption is **villi**.

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