Cellulose is the major component of cell walls of

Options

A. Pythium
B. Xanthomonas
C. Pseudomonas
D. Saccharomyces

Explanation

To determine which organism has cellulose as the major component of its cell wall, we will analyze each of the given options step by step.

### Step 1: Analyze Pythium
- Pythium belongs to the group known as Phycomycetes.
- The cell wall of Pythium is primarily composed of cellulose.
- Therefore, Pythium has cellulose as the major component of its cell wall.

### Step 2: Analyze Xanthomonas
- Xanthomonas is classified as a type of Eubacteria.
- The cell wall of Xanthomonas is made up of peptidoglycan, not cellulose.
- Thus, Xanthomonas does not have cellulose as the major component of its cell wall.

### Step 3: Analyze Pseudomonas
- Pseudomonas is also a type of Eubacteria.
- Like Xanthomonas, the cell wall of Pseudomonas is composed of peptidoglycan.
- Therefore, Pseudomonas does not have cellulose as the major component of its cell wall.

### Step 4: Analyze Saccharomyces
- Saccharomyces is a genus of yeast.
- The cell wall of Saccharomyces is primarily made up of chitin, which is different from cellulose.
- Consequently, Saccharomyces does not have cellulose as the major component of its cell wall.

### Conclusion
- After analyzing all the options, we conclude that the organism whose cell wall is primarily made of cellulose is **Pythium**.

### Final Answer
**Pythium** is the organism whose cell wall is primarily composed of cellulose.

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