Reactive oxygen species (ROS) are chemically reactive molecules containing oxygen. Examples include oxygen ions and peroxides. ROS form as a natural byproduct of the normal metabolism of oxygen and have important roles in cell signaling and homeostasis. However, during times of environmental stress (e.g., UV or heat exposure), ROS levels can increase dramatically. This may result in significant damage to cell structures. Cumulatively, this is known as oxidative stress. ROS are also generated by exogenous sources such as ionizing radiation.
Other articles related to "reactive oxygen species, oxygen":
... Reactive oxygen species are dangerous by-products that sometimes result from the use of oxygen in organisms ... Important examples include oxygen free radicals such as the highly-dangerous superoxide O2-, and the less harmful hydrogen peroxide (H2O2) ... system of higher organisms, however, create peroxide, superoxide, and singlet oxygen to destroy invading microbes ...
... Diels-Alder reaction with singlet oxygen, oxidative damage of DNA. ...
... stress and it depresses/scavenges the formation of toxic reactive oxygen species, e.g ... as reductant in the enzymatic detoxification of reactive oxygen species in the glutathione-ascorbate cycle and as thiol buffer in the protection of proteins via direct reaction with reactive oxygen species or ...
... and hydroxyl, which can recombine to form gaseous hydrogen, oxygen, hydrogen peroxide, hydroxyl radicals, and peroxide radicals ... organisms, which are composed mostly of water, majority of the damage is caused by the reactive oxygen species, free radicals produced from water ... systems of nuclear reactors, the formation of free oxygen would promote corrosion and is counteracted by addition of hydrogen to the cooling water ...
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