What is the correct fate of ammonium ions in plants ?

Options

A. It undergoes transamination with alpha ketogutaric acid to form glumate acid which further undergoes reductive amination to form other amino acids
B. It undergoes reductive amination with alpha ketoglutaric acid to glumatine which further undergoes transamination to form other amino acids .
C. It undergoes transamination with alpha ketogutaric acid to glutamine which further undergoes reductive amination to form other amino acids
D. It undergoes reductive amination with alpha ketoglutaric acid to glumate which further undergoes transamination to form other amino acids .

Answer

### Step-by-Step Solution:

1. **Understanding Nitrogen Fixation**:
- Nitrogen in the atmosphere is fixed by prokaryotic bacteria, converting it into ammonia (NH3). This process is essential for making nitrogen available to plants.

2. **Conversion to Ammonium Ions**:
- The ammonia produced is then converted into ammonium ions (NH4+) in the soil, especially in acidic conditions.

3. **Role of Ammonium Ions in Plants**:
- Ammonium ions are taken up by plants through their roots. While ammonium can be toxic in high concentrations, plants utilize it effectively for growth.

4. **Synthesis of Amino Acids**:
- Inside the plant, ammonium ions undergo a process called reductive amination. In this process, ammonium ions react with alpha-ketoglutaric acid to form glutamic acid.

5. **Enzymatic Reaction**:
- The reaction is catalyzed by the enzyme glutamate dehydrogenase. The overall reaction can be summarized as:
- NH4+ + alpha-ketoglutaric acid + NADPH → Glutamate + NADP+ + H2O

6. **Formation of Other Amino Acids**:
- Glutamic acid can then be further transformed into other amino acids through transamination processes, contributing to protein synthesis in plants.

7. **Conclusion**:
- The correct fate of ammonium ions in plants is that they undergo reductive amination with alpha-ketoglutaric acid to form glutamate, which can then be converted into other amino acids.

### Final Answer:
The correct fate of ammonium ions in plants is that they undergo reductive amination with alpha-ketoglutaric acid to form glutamate, which further undergoes transamination to form other amino acids.