In small intestine,acitve absorption occurs in case of

Options

A. Glucose
B. Amino acids
C. `Na^+`
D. All the above

Answer

**Step-by-Step Solution:**

1. **Understanding Active Absorption**: Active absorption refers to the process by which certain substances are absorbed against their concentration gradient, requiring energy in the form of ATP. This is crucial for the absorption of nutrients in the small intestine.

2. **Identifying Substances Absorbed Actively**: In the small intestine, several key nutrients are absorbed through active transport. These include:
- **Glucose**: A simple sugar that is a primary energy source for the body.
- **Amino Acids**: The building blocks of proteins, essential for various bodily functions.
- **Sodium Ions**: Important for maintaining fluid balance and nerve function.

3. **Location of Absorption**: The small intestine is the main site for nutrient absorption, with its structure optimized for this function. It is approximately 7 meters long, providing a large surface area for absorption.

4. **Conclusion**: Since glucose, amino acids, and sodium ions are all absorbed through active transport in the small intestine, the correct answer to the question is "all of the above."

**Final Answer**: Active absorption occurs in the case of glucose, amino acids, sodium ions, and all of the above.

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