Archaebacteria differ from other bacteria in having a:

Options

A. Dillerent cell wall structure
B. Mode of nutrition
C. Cell shape
D. Mode of reproduction

Answer

To solve the question regarding how Archaebacteria differ from other bacteria, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Classification**: Understand that Archaebacteria belong to the Kingdom Monera, which includes all unicellular prokaryotes. This is the first step in differentiating them from other types of bacteria.

2. **Understand the Unique Characteristics**: Recognize that Archaebacteria have unique features that set them apart from Eubacteria (the other main group of bacteria). One of the most significant differences is their cell wall structure.

3. **Explore the Types of Archaebacteria**: Archaebacteria are classified into three main groups:
- **Halophiles**: These organisms thrive in high-salt environments.
- **Thermoacidophiles**: These are found in extremely hot and acidic environments, such as hot springs.
- **Methanogens**: These bacteria produce methane and are often found in the digestive tracts of ruminant animals.

4. **Focus on Cell Wall Composition**: The cell walls of Archaebacteria contain unique compounds, such as pseudopeptidoglycan, which differ from the peptidoglycan found in Eubacteria. This is a crucial point of differentiation.

5. **Conclude with the Correct Answer**: Based on the unique cell wall structures of Archaebacteria, the correct answer to the question is that they differ from other bacteria in having a **different cell wall structure**.

### Final Answer:
Archaebacteria differ from other bacteria in having a **different cell wall structure**.

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