Give one example each of `alpha`-amino acid which is achiral and `alpha`-amino acid having more than one chiral centre.

Explanation

To answer the question, we need to identify two types of alpha-amino acids: one that is achiral and one that has more than one chiral center.

### Step-by-Step Solution:

1. **Identify an achiral alpha-amino acid:**
- The simplest example of an achiral alpha-amino acid is **Glycine**.
- Glycine has the chemical structure: NH2-CH2-COOH.
- In this structure, the central carbon atom (the alpha carbon) is attached to two hydrogen atoms, an amino group (NH2), and a carboxylic acid group (COOH).
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