The amino acid which plays a central role in nitrogen metabolism is/are

Options

A. Glutamic acid
B. ` alpha ` - Ketoglutaric acid
C. Aspartic acid
D. Double aminated keto acids.

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogen Metabolism**: Nitrogen metabolism refers to the processes by which organisms utilize nitrogen-containing compounds. Amino acids play a crucial role in these processes.

2. **Identifying Key Amino Acids**: The question asks for the amino acid that plays a central role in nitrogen metabolism. The options provided are:
- Glutamic acid
- Alpha-ketoglutaric acid
- Aspartic acid
- Double-aminated keto acid

3. **Role of Glutamic Acid**: Among the options, glutamic acid (also known as glutamate) is particularly important in nitrogen metabolism. It is involved in the process of transamination, where it collects nitrogen from other amino acids.

4. **Transamination Process**: During transamination, glutamic acid can accept an amino group from another amino acid, forming a new amino acid and producing alpha-ketoglutarate. This process is essential for the synthesis and degradation of amino acids.

5. **Nitrogen Release and Urea Cycle**: Glutamic acid can also release nitrogen in the form of ammonia or transfer it to aspartate. Aspartate is then utilized in the urea cycle, which is a key pathway for nitrogen excretion in organisms.

6. **Conclusion**: Based on the above reasoning, the amino acid that plays a central role in nitrogen metabolism is glutamic acid.

**Final Answer**: Glutamic acid

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