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  2. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    The most celebrated link between oxygen and evolution occurred at the end of the last of the Snowball Earth glaciations, where complex multicellular life is first found in the fossil record. Under low oxygen concentrations and before the evolution of nitrogen fixation , biologically-available nitrogen compounds were in limited supply, [ 16 ...

  3. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    These plants are then digested by animals who use the nitrogen compounds to synthesise their proteins and excrete nitrogen-bearing waste. Finally, these organisms die and decompose, undergoing bacterial and environmental oxidation and denitrification , returning free dinitrogen to the atmosphere.

  4. Neoproterozoic oxygenation event - Wikipedia

    en.wikipedia.org/wiki/Neoproterozoic_oxygenation...

    The evolution and radiation of nitrogen-fixing bacteria and non-nitrogen-fixing picocyanobacteria capable of occupying marine planktonic niches and consequent changes to the nitrogen cycle during the Cryogenian are believed to be a culprit behind the rapid oxygenation of and removal of carbon dioxide from the atmosphere, which also helps ...

  5. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    The nitrogen cycle is an important process in the ocean as well. While the overall cycle is similar, there are different players [42] and modes of transfer for nitrogen in the ocean. Nitrogen enters the water through the precipitation, runoff, or as N 2 from the atmosphere. Nitrogen cannot be utilized by phytoplankton as N

  6. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    This unstable atmosphere was short-lived and condensed shortly after to form the bulk silicate Earth, leaving behind an atmosphere largely consisting of water vapor, nitrogen, and carbon dioxide, with smaller amounts of carbon monoxide, hydrogen, and sulfur compounds.

  7. Atmosphere of Earth - Wikipedia

    en.wikipedia.org/wiki/Atmosphere_of_Earth

    About 3.4 billion years ago, nitrogen formed the major component of the then-stable "second atmosphere". The influence of the evolution of life has to be taken into account rather soon in the history of the atmosphere because hints of earliest life forms appeared as early as 3.5 billion years ago. [ 48 ]

  8. Carbon-14 - Wikipedia

    en.wikipedia.org/wiki/Carbon-14

    Carbon-14 decays into nitrogen-14 (14 N) through beta decay. [6] A gram of carbon containing 1 atom of carbon-14 per 10 12 atoms, emits ~0.2 [7] beta (β) particles per second. The primary natural source of carbon-14 on Earth is cosmic ray action on nitrogen in the atmosphere, and it is therefore a cosmogenic nuclide.

  9. Diazotroph - Wikipedia

    en.wikipedia.org/wiki/Diazotroph

    Diazotroph fertilizer is a kind of biofertilizer that can use nitrogen-fixing microorganisms to convert molecular nitrogen (N 2) into ammonia (which is the formation of nitrogen available for the crops to use). These nitrogen nutrients then can be used in the process of protein synthesis for the plants.