question_answer 79)

  Protein found in a biological system with a unique three-dimensional structure and biological activity is called a native protein. When a protein in its native form, is subjected to a physical change like change in temperature or a chemical change like, change in pH, denaturation of protein takes place. Explain the cause.

Answer:

                  Due to a physical or a chemical change, H-bonds in proteins are broken, globules unfold and helices get uncoiled to form a thread like molecule (refer to Fig. 14.19, page 14/29). As a result, secondary and tertiary structures are destroyed and the protein loses its biologicaTactivity. This process is called denaturation of proteins.