A molecule of lactose is formed by a glycosidic bond between

Options

A. Galactose and fructose
B. Galactose and galactose
C. Galactose and glucose
D. Fructose and galactose

Answer

To determine which molecules form lactose through a glycosidic bond, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Lactose**:
- Lactose is a disaccharide, which means it is composed of two monosaccharides linked together.

2. **Identify the Monosaccharides Involved**:
- The common monosaccharides are glucose, galactose, and fructose. We need to identify which two of these combine to form lactose.

3. **Recall the Composition of Lactose**:
- Lactose is specifically known to be made up of galactose and glucose.

4. **Determine the Type of Bond**:
- The bond that connects the two monosaccharides in lactose is a glycosidic bond. In the case of lactose, it is a beta-1,4-glycosidic bond.

5. **Conclusion**:
- Therefore, lactose is formed by a glycosidic bond between galactose and glucose.

### Final Answer:
A molecule of lactose is formed by a glycosidic bond between **galactose and glucose**.

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