Lactose composed of-

Options

A. Glucose + galactose
B. Glucose+ fructose
C. Glucose+ glucose
D. Glucose+ mannose

Answer

**Step-by-Step Solution:**

1. **Identify the Type of Carbohydrate**: Lactose is classified as a disaccharide, which means it is composed of two monosaccharide units.

2. **Determine the Monomeric Units**: The two monosaccharides that make up lactose are glucose and galactose.

3. **Understand the Role of Enzymes**: The enzyme responsible for breaking down lactose into its constituent monosaccharides (glucose and galactose) is called lactase.

4. **Evaluate the Options**: When presented with multiple-choice options, we need to identify which pair of monosaccharides correctly represents the composition of lactose.
- Option 1: Glucose and Galactose - This is correct.
- Option 2: Glucose and Fructose - This is incorrect; these are the units of sucrose.
- Option 3: Glucose and Glucose - This is incorrect; this would represent maltose.
- Option 4: Glucose and Mannose - This is also incorrect.

5. **Conclusion**: Based on the analysis, the correct answer is that lactose is composed of glucose and galactose.

**Final Answer**: Lactose is composed of glucose and galactose.

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