Question

Each amino acid is unique due to the presence of:

• A. R-group
• B. Carboxylic group
• C. Amine group
• D. Benzene ring

Answer 1

The correct option is A R-group

Amino acids are organic compounds having carbon, hydrogen, oxygen and nitrogen (and sometimes sulphur). Each amino acid has at least one amino group $(-N{H}_2)$ and one carboxyl group (-COOH) around a central carbon atom (⍺-carbon). The remaining valencies of tetravalent carbon are satisfied with one hydrogen atom and one R (alkyl) group. The differences in the R group gives rise to different types of amino acids. Hence, each amino acid is unique due to the presence of R-group. The other three substituents (carboxyl group, amino group and hydrogen) remain the same in all the amino acids.