Which of the following is not a monosaccharides ?

Options

A. Glucose
B. Fructose
C. Cellulose
D. D-Ribose

Answer

To determine which of the following is not a monosaccharide, we need to understand the definition and characteristics of monosaccharides.

### Step-by-Step Solution:

1. **Definition of Monosaccharides**: Monosaccharides are the simplest form of carbohydrates, consisting of a single sugar unit. They cannot be hydrolyzed into simpler sugars.

2. **General Formula**: The general formula for monosaccharides is \( C_nH_{2n}O_n \), where \( n \) typically ranges from 3 to 7.

3. **Identifying Monosaccharides**: Common examples of monosaccharides include:
- **Glucose**: \( C_6H_{12}O_6 \)
- **Fructose**: \( C_6H_{12}O_6 \)
- **D-Ribose**: \( C_5H_{10}O_5 \)

4. **Identifying Non-Monosaccharides**: Polysaccharides are carbohydrates that consist of long chains of monosaccharide units. They can be hydrolyzed into multiple monosaccharides. Examples include:
- **Cellulose**: A polysaccharide made up of glucose units, with a general formula of \( (C_6H_{10}O_5)_n \), where \( n \) can be very large (100 to 3000).

5. **Conclusion**: Among the options provided, cellulose is not a monosaccharide; it is a polysaccharide. Therefore, the answer to the question is **cellulose**.

### Final Answer:
**Cellulose is not a monosaccharide.**

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