What are the similarities and differences in the structure of amino acids? What determines the uniqueness of the properties of each amino acid?

Amino acids have a dual nature. The presence of a carboxyl group determines their acidic properties, while amino groups determine the basic ones. Most amino acids are amphoteric substances. Amino acids differ from each other in the structure of radicals. The latter may contain an additional carboxyl group or amino group, as well as sulfur atoms capable of forming disulfide bonds between each other, including hydrophilic or hydrophobic atomic groups.
All amino acids consist of an amino group and a carbonyl group, but differ in radical. Each amino acid has its own radical, which is how they differ.

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