Question

........... is the simplest amino acid which is optically inactive.

• A. Glycine
• B. Proline
• C. Leucine
• D. Tryptophan

Answer 1

The correct option is A Glycine

Amino acids are monomer units of proteins. Proteins are formed by joining together of amino acids by peptide bonds. Each amino acid contains an amino group, a carboxylic group, a hydrogen and a substituent R group attached to the $\alpha$-carbon atom. The simplest R group is hydrogen atom as in the case of glycine. Because the R group is a hydrogen atom, the glycine has two hydrogens bonded to the same $\alpha$-carbon atom. Hence, glycine does not contain an asymmetric carbon atom and is optically inactive.