Archaebacteria differ from eubacteria in

Options

A. Mode of nutrition
B. Cell shape
C. Mode of Reproduction Cell
D. Membrane structure.

Answer

**Step-by-Step Solution:**

1. **Understanding the Classification**: Archaebacteria and eubacteria are both classified under the kingdom Monera, which consists of prokaryotic organisms. This means they lack membrane-bound organelles.

2. **Identifying the Key Differences**: The primary differences between archaebacteria and eubacteria can be categorized into various aspects, such as mode of nutrition, cell shape, mode of reproduction, and membrane structure.

3. **Analyzing Membrane Structure**:
- Archaebacteria have unique membrane structures composed of glycoether lipids, which allow them to thrive in extreme environments (extremophiles).
- Eubacteria, on the other hand, have a different membrane structure that typically includes phospholipids and is not adapted to extreme conditions.

4. **Evaluating Other Options**:
- **Mode of Nutrition**: Both archaebacteria and eubacteria can have diverse modes of nutrition (autotrophic or heterotrophic).
- **Cell Shape**: Both groups can exhibit various cell shapes (cocci, bacilli, spirilla).
- **Mode of Reproduction**: Both groups reproduce asexually, primarily through binary fission.

5. **Conclusion**: The most significant difference between archaebacteria and eubacteria lies in their membrane structure. Therefore, the correct answer is that archaebacteria differ from eubacteria in their membrane structure.

**Final Answer**: Archaebacteria differ from eubacteria in their membrane structure.

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