Final answer:
Denaturation of proteins occurs when protein structures lose their shape, resulting in proteins becoming insoluble in water.
Step-by-step explanation:
Denaturation of proteins occurs when protein structures lose their shape due to changes in temperature, pH, exposure to chemicals, or other factors. While the primary structure of a protein remains intact during denaturation, the folding of the protein is lost. This loss of structure can lead to proteins becoming insoluble in water. For example, when an egg is fried or boiled, the albumin protein in the liquid egg white denatures and changes from a clear substance to an opaque white substance.