A tetrapeptide has -COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with - N H 2 group attached to a chiral center is

Step-by-step solution

No. of possible sequences (primary structures) with - N H 2 group attached to a chiral center is 4. Since -COOH group is attached to alanine, one terminal of the tetrapeptide contains alanine. Thus, its position is fixed. Glycine is achiral whereas valine and phenylalanine are chiral. Thus, -NH 2 group is attached to either valine or phenylalanine. Thus following are the four possible combinations of the tetrapeptide. H 2 ​ N − Val − Gly − Phe − Ala − COOH H 2 ​ N &#