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  2. Great Oxidation Event - Wikipedia

    en.wikipedia.org/wiki/Great_Oxidation_Event

    Oxygen, O 2, meanwhile, was present in the atmosphere at just 0.001% of its present atmospheric level. [12] [13] The Sun shone at about 70% of its current brightness 4 billion years ago, but there is strong evidence that liquid water existed on Earth at the time. A warm Earth, in spite of a faint Sun, is known as the faint young Sun paradox. [14]

  3. Dioxygen in biological reactions - Wikipedia

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

    Monooxygenase uses oxygen for many oxidation reactions in the body. Oxygen that is suspended in the blood plasma equalizes into the tissue according to Henry's law. Carbon dioxide, a waste product, is released from the cells and into the blood, where it is converted to bicarbonate or binds to hemoglobin for transport to the lungs.

  4. Oxygen evolution - Wikipedia

    en.wikipedia.org/wiki/Oxygen_evolution

    Photosynthetic oxygen evolution is the fundamental process by which oxygen is generated in the earth's biosphere. The reaction is part of the light-dependent reactions of photosynthesis in cyanobacteria and the chloroplasts of green algae and plants. It utilizes the energy of light to split a water molecule into its protons and electrons for ...

  5. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    The common allotrope of elemental oxygen on Earth is called dioxygen, O 2, the major part of the Earth's atmospheric oxygen (see Occurrence). O 2 has a bond length of 121 pm and a bond energy of 498 kJ/mol. [42] O 2 is used by complex forms of life, such as animals, in cellular respiration. Other aspects of O

  6. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    The increase in oxygen concentrations had wide ranging and significant impacts on Earth's biosphere. Most significantly, the rise of oxygen and the oxidative depletion of greenhouse gases (especially atmospheric methane ) due to the GOE led to an icehouse Earth that caused a mass extinction of anaerobic microbes , but paved the way for the ...

  7. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]

  8. 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.

  9. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    The flow of energy in an ecosystem is an open system; the Sun constantly gives the planet energy in the form of light while it is eventually used and lost in the form of heat throughout the trophic levels of a food web. Carbon is used to make carbohydrates, fats, and proteins, the major sources of food energy. These compounds are oxidized to ...