Biogas is produced by the members which belong to

Options

A. Eubacteria
B. Archaebacteria
C. Mycoplasmas
D. cyabobacteria

Answer

**Step-by-Step Solution:**

1. **Understanding Biogas Production**: Biogas is primarily composed of methane, which is produced during the anaerobic digestion of organic matter, such as cow dung.

2. **Identifying the Relevant Groups**: The question provides four options: Eubacteria, Archaeobacteria, Mycoplasmas, and Cyanobacteria. We need to determine which of these groups is responsible for biogas production.

3. **Reviewing Bacterial Classes**:
- **Eubacteria**: Known as true bacteria, they are diverse and include many types of bacteria.
- **Archaeobacteria**: Also known as Archaea, these are ancient bacteria that thrive in extreme environments. They include methanogens, which are specifically known for producing methane.
- **Mycoplasmas**: These are a type of bacteria that lack a cell wall and are not typically involved in methane production.
- **Cyanobacteria**: These are photosynthetic bacteria and do not produce biogas.

4. **Focusing on Methanogens**: Methanogens are a subgroup of Archaeobacteria that produce methane as a metabolic byproduct. They are found in the digestive systems of ruminant animals like cows and buffaloes, where they break down organic matter and produce biogas.

5. **Conclusion**: Since methanogens, which are responsible for biogas production, belong to the group of Archaeobacteria, the correct answer to the question is **B. Archaeobacteria**.

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