Which one is the correct sequene of molecules during biological nitrogen fixation?

Options

A. Nitrogen - diamide - hydrazine - ammonia
B. Nitrogen - hydrazine - dimide - ammonia
C. Nitrogen - ammonia - a ketoglutraic acid - glutamic acid
D. Nitrogen - nitrite - nitrate - amino acid

Answer

**Step-by-Step Solution:**

1. **Understanding Biological Nitrogen Fixation:**
- Biological nitrogen fixation is a process where atmospheric nitrogen (N₂) is converted into ammonia (NH₃) by certain bacteria, primarily found in the root nodules of leguminous plants.

2. **Identifying the Initial Molecule:**
- The process begins with atmospheric nitrogen (N₂). This nitrogen is taken up by nitrogen-fixing bacteria such as Rhizobium.

3. **Role of Nitrogenase:**
- The enzyme nitrogenase plays a crucial role in this process. It catalyzes the reduction of nitrogen gas (N₂) to form diimide (N₂H₂).

4. **Formation of Hydrazine:**
- The diimide (N₂H₂) then undergoes further reduction to produce hydrazine (N₂H₄).

5. **Final Product - Ammonia:**
- Finally, hydrazine (N₂H₄) is reduced to form ammonia (NH₃), which is the usable form of nitrogen for plants.

6. **Correct Sequence of Molecules:**
- Therefore, the correct sequence of molecules during biological nitrogen fixation is:
- Nitrogen (N₂) → Diimide (N₂H₂) → Hydrazine (N₂H₄) → Ammonia (NH₃).

**Final Answer:**
- The correct sequence of molecules during biological nitrogen fixation is: Nitrogen, Diimide, Hydrazine, Ammonia.

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