question_answer

Which of the following amino acid is optically inactive?

A)  Phenyl alanine

B)  Glycine

C)  Glutamic acid  

D)  Asparagine

Correct Answer: B

Solution :

                 Key Idea: Optical isomers have all 4 different groups attached to same carbon atom. Phenylalanine, glutamic acid aspargine have 4 different groups attached to carbon atom. But glycine has two identical groups attached to it. Therefore, glycine does not show optical activity.