BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Curdling of milk is another example of denaturation of proteins where the formation of lactic acid by microbial action results in denaturation.

Detailed explanation-2: -When a solution of a protein is boiled, the protein frequently becomes insoluble-i.e., it is denatured-and remains insoluble even when the solution is cooled. The denaturation of the proteins of egg white by heat-as when boiling an egg-is an example of irreversible denaturation.

Detailed explanation-3: -Protein is uncoiled and its shape is destroyed. Characteristic biological activity is lost. Examples include the following : (i) Boiling of egg coagulates egg white. (ii) Milk is converted to curd.

Detailed explanation-4: -Hence, the correct answer is ‘Distilled water’.

Detailed explanation-5: -denaturation, in biology, process modifying the molecular structure of a protein. Denaturation involves the breaking of many of the weak linkages, or bonds (e.g., hydrogen bonds), within a protein molecule that are responsible for the highly ordered structure of the protein in its natural (native) state.