Which of the following is the simplest amino acid?

Options

A. tyrosine
B. asparagine
C. glycine
D. alanine

Answer

To determine which of the following is the simplest amino acid, we will analyze the given options: tyrosine, aspartame, glycine, and alanine.

### Step-by-Step Solution:

1. **Understand Amino Acids**: Amino acids are the building blocks of proteins. They can be classified into essential and non-essential amino acids. There are 20 standard amino acids.

2. **Identify the Options**: The options provided are:
- Tyrosine
- Aspartame
- Glycine
- Alanine

3. **Analyze Each Option**:
- **Tyrosine**: This is a larger amino acid with a complex structure. It contains a phenolic group, making it more complex than others.
- **Aspartame**: This is actually a dipeptide (a compound made of two amino acids) and not a single amino acid. Therefore, it cannot be considered.
- **Glycine**: Glycine is the simplest amino acid. It has the chemical formula NH2CH2COOH and does not have a chiral center, making it the smallest and simplest.
- **Alanine**: This amino acid is larger than glycine and has a methyl group (CH3) attached to its carbon.

4. **Conclusion**: Among the options, glycine is the simplest amino acid due to its small size and lack of a chiral center.

### Final Answer:
The simplest amino acid is **glycine**.

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