Lactose is a disaccharide of

Options

A. glucose and fructose
B. glucose and glucose
C. glucose and galactose
D. glucose and maltose.

Explanation

**Step-by-Step Solution:**

1. **Understanding Disaccharides:**
- A disaccharide is a type of carbohydrate formed by the combination of two monosaccharides (simple sugars). The prefix "di-" means two, and "saccharide" refers to sugars.

2. **Identifying the Components of Lactose:**
- Lactose is specifically a disaccharide composed of two monosaccharides: glucose and galactose.

3. **Formation of Lactose:**
- The formation of lactose occurs through a condensation reaction, where a molecule of water is released as glucose and galactose bond together. This bond is formed via a glycosidic linkage.

4. **Role of Enzymes:**
- In humans, the enzyme lactase is responsible for hydrolyzing lactose into its constituent monosaccharides (glucose and galactose) during digestion.

5. **Conclusion:**
- Therefore, we can conclude that lactose is a disaccharide formed from the monosaccharides glucose and galactose.

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