Tow monomers in maltose are :

Options

A. `alpha` - D glucose and `alpha` -D- glucose
B. `alpha` - D -glucose and `beta` -D- glucose
C. `alpha` - D -glucose and `beta` -D- Frutose
D. `alpha` - D -glucose and `beta` -D- galactose

Answer

To solve the question regarding the two monomers in maltose, we can follow these steps:

### Step 1: Understand what maltose is
Maltose is a type of disaccharide, which means it is composed of two monosaccharide units.

**Hint:** Remember that disaccharides are formed from two monosaccharides linked together.

### Step 2: Identify the structure of maltose
Maltose is formed from the condensation of two glucose molecules. Specifically, it is made up of two α-D-glucose units.

**Hint:** Look for the common disaccharides and their monosaccharide components.

### Step 3: Hydrolysis of maltose
When maltose undergoes hydrolysis (a reaction with water), it breaks down into its constituent monosaccharides. In the case of maltose, hydrolysis yields two molecules of α-D-glucose.

**Hint:** Hydrolysis reactions often involve breaking down larger molecules into smaller ones, typically using water.

### Step 4: Analyze the options
Now, let's analyze the options provided:
1. α-D-Glucose and α-D-Glucose
2. α-D-Glucose and β-D-Glucose
3. α-D-Glucose and β-D-Fructose
4. α-D-Glucose and β-D-Galactose

From our understanding, maltose is made up of two α-D-glucose units, which corresponds to the first option.

**Hint:** Match the components of maltose with the options given.

### Step 5: Conclusion
The two monomers in maltose are α-D-Glucose and α-D-Glucose.

**Final Answer:** The correct option is α-D-Glucose and α-D-Glucose.