The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called they perform their usual functions.

denaturation, cannot

Explanation: Proteins function optimally in a particular cellular environment. Conditions that are different from those in the cell result in structural changes in the proteins. The function of a protein is dependent on its structure. A loss of the three-dimensional structure of protein that results in its loss of function is known as denaturation. A protein is said to be denatured if if it undergoes a change in structure or conformation that results in its loss of function. Proteins can be denatured by heat, extremes of pH, by certain miscible organic solvents such as alcohol or acetone, by certain solutes such as urea and by detergents.

When a protein is subjected to a high temperature or extremes of pH, or treated with any of the denaturating agents, the hydrophobic interactions that make up the stable structure of the protein are disrupted and the net charge on the protein is altered, this results in protein loss of function. The denatured protein cannot perform its usual functions in the cell.