Final answer:
When heated, a protein molecule becomes denatured due to the breakage of hydrogen bonds and other interactions, leading to the loss of its functional shape.
Step-by-step explanation:
On being heated, a protein molecule will become denatured as a result of the breakage of hydrogen bonds and other stabilizing interactions such as disulfide linkages and ionic bonds. Proteins are composed of complex structures held together by these bonds, and upon heating or exposure to UV radiation, they receive kinetic energy which makes their atoms vibrate more rapidly, leading to the disruption of these weak interactions and causing denaturation. While the primary structure of proteins (the sequence of amino acids) is relatively stable, the secondary, tertiary, and quaternary structures are more vulnerable to denaturation. Some proteins can re-nature when the source of denaturation is removed, but others may form insoluble aggregates and are rendered permanently dysfunctional.