Nitrosomonas and Nitrosococcus promote

Options

A. reduction of ammonia
B. oxidation of nitrite
C. reduction of nitrate
D. oxidation of ammonia

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the role of the bacteria Nitrosomonas and Nitrosococcus. These bacteria are involved in the nitrogen cycle, which is crucial for converting nitrogen into forms that plants can utilize.

2. **Identifying the Process**: Nitrosomonas and Nitrosococcus are known as nitrifying bacteria. Their primary function is to facilitate the conversion of ammonia into nitrites.

3. **Nitrogen Cycle Overview**: In the nitrogen cycle, atmospheric nitrogen is converted into ammonia through nitrogen fixation. This ammonia can then be further processed by bacteria.

4. **Role of Nitrosomonas and Nitrosococcus**: These bacteria specifically oxidize ammonia (NH3) into nitrite (NO2-). This is a critical step in the nitrogen cycle, as nitrites can then be converted into nitrates (NO3-) by other bacteria.

5. **Conclusion**: Therefore, the correct answer to the question is that Nitrosomonas and Nitrosococcus promote the oxidation of ammonia.

**Final Answer**: Nitrosomonas and Nitrosococcus promote the oxidation of ammonia.

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