Amino acid playing an important role in nitrogen metabolism is

Options

A. Tryptophan
B. Methionine
C. Glutamic acid
D. Phenylalanine

Answer

To determine which amino acid plays an important role in nitrogen metabolism, we can analyze the options provided and their functions:

1. **Understanding Nitrogen Metabolism**: Nitrogen metabolism involves the conversion of nitrogen into usable forms such as nitrate and nitrite. This process is crucial for the synthesis of amino acids and proteins in plants.

2. **Evaluating the Options**:
- **Tryptophan**: This amino acid is known for its role in the synthesis of serotonin and melatonin. However, it is not involved in promoting nitrogen metabolism; instead, it can delay it. Thus, it is not the correct answer.
- **Methionine**: Methionine is involved in the synthesis of ethylene and polyamines, which are important for plant growth and development. However, it does not play a significant role in nitrogen metabolism, so it is also not the correct answer.
- **Glutamic Acid**: This amino acid is crucial in nitrogen metabolism. It participates in transamination and amination reactions, which are essential for the incorporation of nitrogen into organic molecules. Therefore, glutamic acid is a key player in nitrogen metabolism.
- **Phenylalanine**: This amino acid is primarily involved in plant defense mechanisms and does not significantly contribute to nitrogen metabolism.

3. **Conclusion**: Among the options evaluated, glutamic acid is the amino acid that plays the most important role in nitrogen metabolism.

**Final Answer**: Glutamic acid

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