`N_(2)+8_(e-)+8H^(+)+16ATP rarr 2NH3+H_(2)+16ADP+16Pi` The above equation refers to

Options

A. (a) ammonification
B. (b) nitrificaion
C. (c) nitrogen fixation
D. (d) denitrification

Answer

The equation provided refers to the process of nitrogen fixation. Let's break down the reasoning step by step:

### Step-by-Step Solution:

1. **Identify the Reactants and Products**:
The equation shows that nitrogen gas (N₂) is being converted into ammonia (NH₃), along with the production of hydrogen gas (H₂), ADP, and inorganic phosphate (Pi).

2. **Understanding the Process**:
Nitrogen fixation is the process where atmospheric nitrogen (N₂) is converted into a more usable form, ammonia (NH₃). This is crucial because plants cannot directly utilize atmospheric nitrogen.

3. **Role of Energy and Reducing Agents**:
The reaction requires energy, which is provided by ATP, and a reducing agent, which in this case is NADPH₂. These components are derived from the respiration of host cells.

4. **Enzymatic Action**:
The conversion of nitrogen to ammonia is facilitated by an enzyme called nitrogenase. This enzyme is found in nitrogen-fixing bacteria, which play a vital role in this process.

5. **Intermediate Steps**:
The nitrogen is first converted to intermediates such as hydrazine (N₂H₄) before finally being reduced to ammonia (NH₃). This indicates that the reaction involves multiple steps of reduction.

6. **Conclusion**:
Since the equation describes the conversion of atmospheric nitrogen into ammonia, it clearly aligns with the process of nitrogen fixation.

### Final Answer:
The above equation refers to **C) nitrogen fixation**.

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