Methanogens belong to

Options

A. Eubacteria
B. Archaebacteria
C. Dinoflagellates
D. Slime moulds

Answer

**Step-by-Step Solution:**

1. **Understanding Methanogens**: Methanogens are microorganisms that produce methane as a metabolic by-product in anoxic conditions. They are known for their role in the digestion of cellulose in ruminant animals.

2. **Examples of Methanogens**: Common examples of methanogens include Methanobacterium and Methanococcus. These bacteria thrive in harsh environments, such as the digestive tracts of ruminant animals like cattle, buffalo, goats, and sheep.

3. **Environmental Conditions**: Methanogens are adapted to live in extreme conditions, such as high temperatures and acidic environments, which makes them unique among microorganisms.

4. **Classification of Methanogens**: Methanogens are classified under the domain Archaea, specifically within the group known as "Archaebacteria" or "RK bacteria". This group is distinct from Eubacteria (true bacteria).

5. **Other Classes of Archaea**: In addition to methanogens, Archaea includes other classes such as:
- Thermoacidophiles: These bacteria can survive in high-temperature and acidic environments, such as hot springs.
- Halophiles: These bacteria thrive in high-salt environments, such as salt flats and salt mines.

6. **Conclusion**: Based on the classification, methanogens belong to the group of Archaea, specifically classified as RK bacteria.

**Final Answer**: Methanogens belong to RK bacteria (Archaea).

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