The molecule that contains both amino and carboxylic acid functional groups is an amino acid.

Here's a breakdown:

* Amino group: -NH2

* Carboxylic acid group: -COOH

Amino acids are the building blocks of proteins. They have a central carbon atom (alpha carbon) bonded to:

* An amino group (NH2)

* A carboxylic acid group (COOH)

* A hydrogen atom (H)

* A side chain (R group), which varies depending on the specific amino acid.

The presence of both amino and carboxylic acid groups allows amino acids to link together via peptide bonds to form long chains, which make up proteins.