Question

Cellulose is a homopolymer of:

• A. Alpha glucose
• B. Beta glucose
• C. Alpha fructose
• D. Beta fructose

Hint:

Remember the key difference: \(\alpha\)-glucose polymers (starch, glycogen) are for energy storage and are generally digestible by animals. \(\beta\)-glucose polymers (cellulose) are for structure and are generally indigestible by animals without the help of symbiotic microorganisms.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
A homopolymer is a polymer consisting of identical monomer units. Cellulose is a major structural polysaccharide found in the cell walls of plants. The question asks for its constituent monomer.

Step 2: Detailed Explanation:
- Polysaccharides are polymers of monosaccharides. The two most common polysaccharides made of glucose are starch and cellulose.
- The difference between them lies in the isomeric form of the glucose monomer and the resulting glycosidic bond.
- Starch and glycogen are polymers of alpha-glucose, linked by \(\alpha\)-1,4 glycosidic bonds. This linkage results in a helical polymer structure, suitable for energy storage.
- Cellulose is a polymer of beta-glucose, linked by \(\beta\)-1,4 glycosidic bonds. This linkage results in long, straight, unbranched chains. These chains can lie parallel to each other and form strong hydrogen bonds, creating rigid microfibrils that are ideal for structural support.
- Fructose is a different monosaccharide, a ketose, while glucose is an aldose.

Step 3: Final Answer:
Cellulose is a linear homopolymer composed of repeating units of beta-glucose. Therefore, option (B) is correct.