What is the structural flat representation of an amino acid molecule?
An amino acid has a central carbon to which a carboxyl group binds on a side and to which a -R (variable radical) binds on the opposite side. In the perpendicular direction of those ligands an amine group binds the central carbon on one side and hydrogen binds on the opposite side.
The bind of the carboxyl group to a carbon where hydrogen is laterally attached is responsible for the name "acid" in amino acids. The bound of an amine group in the central carbon gives the name "amino".
Protein Structure Review - Image Diversity: carboxyl group