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  2. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    The appearance of highly reactive free oxygen, which can oxidize organic compounds (especially genetic materials) and thus is toxic to the then-mostly anaerobic biosphere, may have caused the extinction/extirpation of many early organisms on Earth – mostly archaeal colonies that used retinal to use green-spectrum light energy and power a form ...

  3. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    In plants, algae, and cyanobacteria, photosynthesis releases oxygen. This oxygenic photosynthesis is by far the most common type of photosynthesis used by living organisms. Some shade-loving plants (sciophytes) produce such low levels of oxygen during photosynthesis that they use all of it themselves instead of releasing it to the atmosphere. [12]

  4. Oxygen evolution - Wikipedia

    en.wikipedia.org/wiki/Oxygen_evolution

    Oxygen evolution is the chemical process of generating elemental diatomic oxygen (O 2) by a chemical reaction, usually from water, the most abundant oxide compound in the universe. Oxygen evolution on Earth is effected by biotic oxygenic photosynthesis, photodissociation, hydroelectrolysis, and thermal decomposition of various oxides and oxyacids.

  5. Dioxygen in biological reactions - Wikipedia

    en.wikipedia.org/wiki/Dioxygen_in_biological...

    Free oxygen is produced in the biosphere through photolysis (light-driven oxidation and splitting) of water during photosynthesis in cyanobacteria, green algae, and plants. During oxidative phosphorylation in cellular respiration , oxygen is reduced to water, thus closing the biological water-oxygen redox cycle.

  6. Purple Earth hypothesis - Wikipedia

    en.wikipedia.org/wiki/Purple_Earth_hypothesis

    However, when porphyrin-based photoautotrophs evolved and started to photosynthesize, which included both the primitive purple bacteria using bacteriochlorophyll and cyanobacteria using chlorophyll, highly reactive dioxygen was released as a byproduct of water splitting and started to accumulate, first in the ocean and then in the atmosphere.

  7. Pumping oxygen into deep areas of Lake Hopatcong may solve ...

    www.aol.com/pumping-oxygen-deep-areas-lake...

    A deep-water oxygenation system could be in the cards for Lake Hopatcong, New Jersey's largest lake, as stakeholders seek to stifle the kind of harmful algal blooms that effectively closed it in 2019.

  8. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Before photosynthesis evolved, Earth's atmosphere had no free diatomic elemental oxygen (O 2). [2] Small quantities of oxygen were released by geological [ 3 ] and biological processes, but did not build up in the reducing atmosphere due to reactions with then-abundant reducing gases such as atmospheric methane and hydrogen sulfide and surface ...

  9. A New Kind of Battery—Oxygen-Ion—Could Change Energy - AOL

    www.aol.com/lifestyle/kind-battery-oxygen-ion...

    It’s incredibly rechargeable, made from safe materials, and—get this—not going to catch on fire.