Nitrifying bacteria

Options

A. oxidise ammonia to nitrates
B. convert free nitrogen to nitrogen compounds
C. convert proteins into ammonia
D. reduce nitrates to free nitrogen

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrifying Bacteria**: Nitrifying bacteria are a group of soil bacteria that play a crucial role in the nitrogen cycle. They are responsible for converting ammonia, which is a toxic compound for plants, into less harmful forms.

2. **Process of Nitrification**: The process carried out by nitrifying bacteria involves two main steps:
- **Ammonia to Nitrite**: The first step involves the oxidation of ammonia (NH₃) into nitrite (NO₂⁻).
- **Nitrite to Nitrate**: The second step involves the further oxidation of nitrite into nitrate (NO₃⁻).

3. **Role in the Nitrogen Cycle**: This entire process of converting ammonia to nitrite and then to nitrate is part of the nitrogen cycle, which is essential for soil fertility and plant nutrition.

4. **Identifying the Correct Option**: Given the options, the correct answer is that nitrifying bacteria oxidize ammonia to nitrate. This aligns with the role of nitrifying bacteria in the nitrogen cycle, confirming their importance in soil health and plant growth.

5. **Conclusion**: Nitrifying bacteria are essential for converting ammonia into nitrate, making nitrogen available for plants, which is vital for their growth and development.

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