Which food substance is absorbed during digestion?

Options

A. Carbohydrates
B. Proteins
C. Vitamins
D. Fats

Answer

**Step-by-Step Solution:**

1. **Identify the Food Substances**: The question asks which food substances are absorbed during digestion. The options provided are carbohydrates, proteins, vitamins, and fats.

2. **Understand Digestion Requirements**: Carbohydrates, proteins, and fats are complex substances that require digestion to break them down into their monomer forms (simple sugars, amino acids, and fatty acids, respectively) before they can be absorbed.

3. **Analyze Vitamins**: Unlike carbohydrates, proteins, and fats, vitamins do not require digestion. They can be absorbed directly in their original form through the gastrointestinal tract (GIT).

4. **Classify Vitamins**: Vitamins can be classified into two categories: fat-soluble and water-soluble.
- Fat-soluble vitamins include A, D, E, and K, which are absorbed along with dietary fat.
- Water-soluble vitamins include B and C, which are absorbed through passive diffusion.

5. **Special Case of Vitamin B12**: Vitamin B12 has a unique absorption mechanism. It requires a protein called intrinsic factor (produced in the stomach) to form a complex that facilitates its absorption in the small intestine.

6. **Conclusion**: Based on the analysis, the food substance that is absorbed during digestion is vitamins, as they do not require digestion like carbohydrates, proteins, and fats.

**Final Answer**: The food substance absorbed during digestion is vitamins.

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