Bacteria differ from other bacteria in having a different cell wall structure which can survive in extreme conditions is

Options

A. Methanogens
B. Thermoacidophiles
C. Cyanobacteria
D. Both (a) and (b)

Answer

To solve the question regarding which type of bacteria differ from other bacteria in having a different cell wall structure that allows them to survive in extreme conditions, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Extremophiles**:
- Extremophiles are organisms that thrive in extreme environmental conditions. This includes high temperatures, extreme acidity, or high salinity.

2. **Identifying the Options**:
- The options provided are:
- A) Methanogens
- B) Thermoacidophiles
- C) Cyanobacteria
- D) Both A and B

3. **Analyzing Methanogens**:
- Methanogens are a type of archaea that produce methane and can survive in anaerobic (no oxygen) environments.
- Their cell wall is made of pseudo-peptidoglycan, which is different from the typical peptidoglycan found in many bacteria.

4. **Analyzing Thermoacidophiles**:
- Thermoacidophiles are organisms that can survive in high temperatures (around 95 degrees Celsius) and low pH (acidic conditions).
- They also have unique cell wall structures that allow them to withstand these extreme conditions.

5. **Analyzing Cyanobacteria**:
- Cyanobacteria are photosynthetic bacteria that do not specifically thrive in extreme conditions. They can survive in a variety of environments but are not classified as extremophiles.

6. **Conclusion**:
- Since both methanogens and thermoacidophiles have unique cell wall structures that allow them to survive in extreme conditions, the correct answer is **D) Both A and B**.

### Final Answer:
**D) Both A and B**