Bacteria Nitrosomonas converts :

Options

A. `NH_(3)` into Nitrite
B. `N_(2)` into `NH_(3)`
C. Nitrite into Nitrate
D. `NH_(3)` into `N_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrosomonas**: Nitrosomonas is a type of nitrifying bacteria. It plays a crucial role in the nitrogen cycle, specifically in the process of nitrification.

2. **Nitrogen Cycle Overview**: The nitrogen cycle involves several steps where nitrogen is converted into various chemical forms. The main processes include nitrogen fixation, nitrification, and denitrification.

3. **Nitrogen Fixation**: The first step in the nitrogen cycle is nitrogen fixation, where atmospheric nitrogen (N₂) is converted into ammonia (NH₃). This process is carried out by nitrogen-fixing bacteria, not by Nitrosomonas.

4. **Nitrification Process**: After ammonia is formed, nitrification occurs in two main steps:
- **Step 1**: Ammonia (NH₃) is oxidized to nitrite (NO₂⁻) by bacteria such as Nitrosomonas. This is the specific conversion that Nitrosomonas is responsible for.
- **Step 2**: The nitrite (NO₂⁻) is then further oxidized to nitrate (NO₃⁻) by other bacteria, such as Nitrospira or Nitrobacter.

5. **Conclusion**: Therefore, the specific conversion that Nitrosomonas performs is the conversion of ammonia (NH₃) to nitrite (NO₂⁻).

**Final Answer**: Nitrosomonas converts ammonia to nitrite.

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