Which of the following reaction is performed by nitrifying bacteria?

Options

A. `N_(2) to NH_(3)`
B. `NH_(3) to NO_(3)`
C. Amino acid `to NH_(3)`
D. `NO_(3)^(-) to N_(2)`

Answer

To determine which reaction is performed by nitrifying bacteria, we need to understand the processes involved in nitrogen cycling, particularly nitrification. Let's break down the steps:

### Step-by-Step Solution:

1. **Understand Nitrification**: Nitrification is a two-step aerobic process where ammonia is converted into nitrate. It involves two groups of bacteria:
- The first group converts ammonia (NH₃) into nitrite (NO₂⁻).
- The second group converts nitrite into nitrate (NO₃⁻).

2. **Identify the Reactions**:
- The first reaction is:
\[ \text{Ammonia (NH₃)} \rightarrow \text{Nitrite (NO₂⁻)} \]
- The second reaction is:
\[ \text{Nitrite (NO₂⁻)} \rightarrow \text{Nitrate (NO₃⁻)} \]

3. **Recognize the Role of Nitrifying Bacteria**:
- Nitrifying bacteria, such as *Nitrosomonas* and *Nitrobacter*, are responsible for these conversions.
- They play a crucial role in the nitrogen cycle by facilitating the transformation of ammonia into forms that plants can utilize.

4. **Evaluate the Given Options**:
- The options provided include:
- Atmospheric Nitrogen is converted into Ammonia (this is nitrogen fixation, not nitrification).
- Ammonia is converted into Nitrate Ion (this is the nitrification process).
- Amino Acid is converted into Ammonia (this is part of the process of ammonification).
- Nitrate Ion is converted into Atmospheric Nitrogen (this is denitrification).

5. **Select the Correct Reaction**:
- The correct reaction performed by nitrifying bacteria is:
\[ \text{Ammonia is converted into Nitrate Ion} \]

### Final Answer:
The reaction performed by nitrifying bacteria is: **Ammonia is converted into Nitrate Ion.**

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