Any Process That Results in a Change in State or Activity of a Cell or an Organism (in Terms of Movement Secretion Enzyme Production Gene Expression Etc.) As a Result of Oxidative Stress a State Often Resulting From Exposure to High Levels of Reactive Oxygen Species E.g. Superoxide Anions Hydrogen Peroxide (h2o2) and Hydroxyl Radicals.
Catalysis of an Oxidation Reduction (redox) Reaction a Reversible Chemical Reaction in Which the Oxidation State of an Atom or Atoms Within a Molecule Is Altered. One Substrate Acts As a Hydrogen or Electron Donor and Becomes Oxidized While the Other Acts As Hydrogen or Electron Acceptor and Becomes Reduced.