Which amino acid among the following is non - essential ?

Options

A. Phenylalanine
B. Leucine
C. Tryptophan
D. Tyrosine

Answer

To determine which amino acid among the given options is non-essential, we need to understand the classification of amino acids into essential and non-essential categories.

### Step-by-Step Solution:

1. **Understand the Definition of Non-Essential Amino Acids**:
- Non-essential amino acids are those that the human body can synthesize on its own. Therefore, they do not need to be obtained directly from the diet.

2. **List the Given Amino Acids**:
- The options provided in the question are:
- Phenylalanine
- Leucine
- Tryptophan
- Tyrosine

3. **Classify Each Amino Acid**:
- **Phenylalanine**: This is an essential amino acid, meaning it must be obtained from the diet.
- **Leucine**: This is also an essential amino acid.
- **Tryptophan**: This is another essential amino acid.
- **Tyrosine**: This is classified as a non-essential amino acid because the body can synthesize it from phenylalanine.

4. **Identify the Non-Essential Amino Acid**:
- Among the options, Tyrosine is the only amino acid that is non-essential.

5. **Conclusion**:
- The correct answer to the question is **Tyrosine**.

### Final Answer:
**Tyrosine** is the non-essential amino acid among the options provided.

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