Final answer:
Superoxide dismutase is an enzyme that neutralizes superoxide free radicals by converting them into less reactive molecules. Specific evidence of its importance includes the up-regulation of its expression in plants during the defense response and the increased resistance to oxidative stress in transgenic plants.
Step-by-step explanation:
Superoxide dismutase is an enzyme that plays a crucial role in getting rid of superoxide free radicals. It neutralizes the superoxide radicals by catalyzing the conversion of them into less reactive molecules, such as hydrogen peroxide or molecular oxygen. Some specific evidence of the importance of superoxide dismutase includes the up-regulation of its expression in plants during the defense response to increase tolerance to pathogens, as well as the increased resistance to oxidative stress in transgenic plants that overexpress chloroplastic Cu/Zn superoxide dismutase.