Last step in biogas production is carried out by

Options

A. Methanobacterium
B. Bacillus
C. Cellulomonas
D. Ruminococcus

Answer

**Step-by-Step Solution:**

1. **Understanding Biogas Production**: Biogas production occurs in four main steps: hydrolysis, acidification, acetogenesis, and methanogenesis. Each step involves different microbial processes.

2. **Identifying the Last Step**: The last step in the biogas production process is called methanogenesis. This step is crucial as it leads to the formation of methane, which is the primary component of biogas.

3. **Role of Methanogens**: In the methanogenesis step, specific microorganisms known as methanogens are responsible for converting substrates into methane. They utilize the products formed in the previous step (acetogenesis), which includes acetate, carbon dioxide, and hydrogen.

4. **Identifying the Correct Bacteria**: Among the options provided (Methanobacterium, Bacillus, Cellulomonas, Ruminococcus), Methanobacterium is a type of methanogen. Therefore, it is the correct answer as it plays a significant role in the last step of biogas production.

5. **Final Answer**: The last step in biogas production is carried out by Methanobacterium (option A).

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