Biomolecules

Proteins are macromolecular polymers of -amino acids bonded by peptide linkage. They on hydrolysis, yield a-amino acids further.

Sucrose is dextrorotatory but on hydrolysis it gives an equimolar mixture of dextrorotatory glucose and laevorotatory fructose. As the laevorotation of fructose is much more than dextrorotation of glucose , therefore, the resulting mixture becomes laevorotatory. Therefore, the hydrolysis of sucrose is accompanied by a change in sign of optical rotation from dextrorotatory to laevorotatory. Therefore, sucrose is called invert sugar.

Amino acids contain amino and carboxyl as functional groups. In aqueous solution, the carboxyl group can lose a proton and amino group can accept a proton, giving rise to a dipolar ion known as Zwitter ion. This is neutral but contains both negative and positive charges.