Which one is wrong about starch

Options

A. Starch is polymer of alpha-glucose
B. It has amylose and amylopectin
C. Amylose is linear with 1, 4-glycosidic linkages
D. Amylopectin is straight chain with 1, 4-glycosidic linkages.

Answer

To determine which statement about starch is incorrect, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Starch Composition**:
- Starch is a polysaccharide made up of glucose units. It consists of two main components: amylose and amylopectin.

2. **Evaluate Option 1**:
- **Statement**: "Starch is a polymer of alpha glucose."
- **Analysis**: This statement is correct. Starch is indeed a polymer made from alpha-D-glucose units linked together.

3. **Evaluate Option 2**:
- **Statement**: "It has amylose and amylopectin."
- **Analysis**: This statement is also correct. Starch is composed of two types of molecules: amylose (linear) and amylopectin (branched).

4. **Evaluate Option 3**:
- **Statement**: "Amylose is linear with 1,4 glycosidic linkages."
- **Analysis**: This statement is correct. Amylose is a linear chain of glucose units connected by alpha-1,4 glycosidic linkages.

5. **Evaluate Option 4**:
- **Statement**: "Amylopectin is straight chain with 1,4 glycosidic linkages."
- **Analysis**: This statement is incorrect. Amylopectin is not a straight chain; it has a branched structure due to the presence of both alpha-1,4 linkages and alpha-1,6 linkages at the branching points.

### Conclusion:
The incorrect statement about starch is **Option 4**: "Amylopectin is straight chain with 1,4 glycosidic linkages."

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