Which of the following microorganism is involved in last step of biogas production ?

Options

A. Methanobacterium
B. Acetobacter
C. Bacillus
D. Streptococcus

Answer

**Step-by-Step Solution:**

1. **Understanding Biogas Production**: Biogas is primarily composed of methane and is produced through the anaerobic digestion of organic matter by microorganisms. The process involves several steps, including hydrolysis, acidogenesis, acetogenesis, and methanogenesis.

2. **Identifying the Last Step**: The last step of biogas production is known as methanogenesis, where methane is produced from the breakdown of organic materials. This step is crucial for the formation of biogas.

3. **Role of Methanogens**: Methanogens are a specific group of microorganisms that play a vital role in the methanogenesis process. They are responsible for converting carbon dioxide and hydrogen into methane.

4. **Common Methanogens**: One of the most common methanogens is Methanobacterium. This bacterium is typically found in anaerobic environments, such as in the sludge of sewage treatment plants and in the rumen of cattle, where it helps in the digestion of cellulose.

5. **Analyzing the Options**: The question provides four options. We need to identify which microorganism is specifically involved in the last step of biogas production, which is methanogenesis.

6. **Conclusion**: Based on the information provided, the microorganism involved in the last step of biogas production is **Methanobacterium**.

**Final Answer**: Methanobacterium

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