Alanine is a simple amino acid, meaning it's a building block for proteins. Here's what makes up an alanine molecule:

* A central carbon atom: This is the core of the molecule.

* An amino group (NH2): Attached to the central carbon.

* A carboxyl group (COOH): Also attached to the central carbon.

* A methyl group (CH3): This is the unique side chain that distinguishes alanine from other amino acids.

Here's a simplified representation:

```

H

|

H-N-C-COOH

|

CH3

```

Key points:

* The amino group and carboxyl group are found in all amino acids.

* The specific side chain (in this case, the methyl group) determines the amino acid's properties and how it interacts with other molecules.

Alanine is often considered a non-polar amino acid because its methyl side chain is hydrophobic (water-repelling).