Successive glucose residues in a cellulose molecule are linked by

Options

A. `alpha1rarr 4` glycosidic linkages
B. `beta1rarr 4` glycosidic linkages
C. `alpha1rarr 6`glycosidic linkages
D. `beta1rarr 6`glycosidic linkages

Answer

To answer the question, "Successive glucose residues in a cellulose molecule are linked by," we need to understand the structure of cellulose and the type of glycosidic linkages involved.

### Step-by-Step Solution:

1. **Identify the Composition of Cellulose**:
- Cellulose is a polysaccharide made up of glucose units. It is a major component of plant cell walls.

2. **Understand Glycosidic Linkages**:
- Glycosidic linkages are the bonds that connect monosaccharides (like glucose) in polysaccharides. The type of glycosidic linkage is determined by the orientation of the hydroxyl (-OH) groups on the glucose molecules.

3. **Determine the Type of Linkage in Cellulose**:
- In cellulose, the glucose units are linked by beta glycosidic linkages. Specifically, the glucose residues are connected by beta-1,4-glycosidic linkages. This means that the first carbon of one glucose molecule (C1) is linked to the fourth carbon of the next glucose molecule (C4) through a beta bond.

4. **Evaluate the Options**:
- The options provided are:
- a) Alpha 1,4 glycosidic linkage
- b) Beta 1,4 glycosidic linkage
- c) Alpha 1,6 glycosidic linkage
- d) Beta 1,6 glycosidic linkage
- Among these, the correct answer is **b) Beta 1,4 glycosidic linkage**.

5. **Conclusion**:
- Therefore, the successive glucose residues in a cellulose molecule are linked by **beta 1,4 glycosidic linkages**.