Cellulose is made of

Options

A. Unbranched chain of glucose molecules linked by `alpha`-1,6 glycosidic bonds
B. Unbranched chain of glucose molecules linked by `beta`-1,4 glycosidic bonds
C. Branched chain of glucose molecules having `alpha`-1,6glycosidic bonds at the site of branching
D. Branched chain of glucose molecules with `alpha`-1,6 glycosidic bonds in the straight chain and `beta`-1, 4 linked bonds at the site of branching .

Answer

**Step-by-Step Solution:**

1. **Understanding Cellulose**: Cellulose is a polysaccharide, which means it is a large molecule made up of many smaller units (monomers). In the case of cellulose, these monomers are glucose molecules.

2. **Linkage of Glucose Molecules**: The glucose molecules in cellulose are linked together by specific types of glycosidic bonds. There are different types of glycosidic bonds, but for cellulose, it is important to identify the correct one.

3. **Identifying the Correct Glycosidic Bond**: In cellulose, the glucose molecules are linked by beta-1,4 glycosidic bonds. This means that the bond forms between the first carbon of one glucose and the fourth carbon of the next glucose in a beta configuration.

4. **Structure of Cellulose**: Cellulose consists of unbranched chains of glucose molecules. This unbranched structure is crucial for its function in providing strength and rigidity to plant cell walls.

5. **Conclusion**: Based on the options provided:
- Option 1 (alpha-1,6 glycosidic bonds) is incorrect.
- Option 2 (beta-1,4 glycosidic bonds) is correct.
- Option 3 (branched chain) is incorrect.
- Option 4 (branched chain with mixed bonds) is also incorrect.

Thus, the correct answer is that cellulose is made of an unbranched chain of glucose molecules linked by beta-1,4 glycosidic bonds.

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