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  2. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen gas is an industrial gas produced by the fractional distillation of liquid air, or by mechanical means using gaseous air (pressurised reverse osmosis membrane or pressure swing adsorption). Nitrogen gas generators using membranes or pressure swing adsorption (PSA) are typically more cost and energy efficient than bulk-delivered ...

  3. Evolution of photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_photosynthesis

    This suggests that it did not have a key role in invoking C 4 evolution. [36] Grasses themselves (the group which would give rise to the most occurrences of C 4) had probably been around for 60 million years or more, so had had plenty of time to evolve C 4, [44] [45] which, in any case, is present in a diverse range of groups and thus evolved ...

  4. Cambrian explosion - Wikipedia

    en.wikipedia.org/wiki/Cambrian_explosion

    Cyanobacteria were the first organisms to evolve the ability to photosynthesize, introducing a steady supply of oxygen into the environment. [130] Initially, oxygen levels did not increase substantially in the atmosphere. [131] The oxygen quickly reacted with iron and other minerals in the surrounding rock and ocean water.

  5. History of the periodic table - Wikipedia

    en.wikipedia.org/wiki/History_of_the_periodic_table

    This is an accepted version of this page This is the latest accepted revision, reviewed on 17 November 2024. Development of the table of chemical elements The American chemist Glenn T. Seaborg —after whom the element seaborgium is named—standing in front of a periodic table, May 19, 1950 Part of a series on the Periodic table Periodic table forms 18-column 32-column Alternative and ...

  6. Evolution of cells - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_cells

    The initial development of the cell marked the passage from prebiotic chemistry to partitioned units resembling modern cells. The final transition to living entities that fulfill all the definitions of modern cells depended on the ability to evolve effectively by natural selection. This transition has been called the Darwinian transition.

  7. Abiogenesis - Wikipedia

    en.wikipedia.org/wiki/Abiogenesis

    Panspermia did not get much scientific support because it was largely used to deflect the need of an answer instead of explaining observable phenomena. Although the interest in panspermia grew when the study of meteorites found traces of organic materials in them, it is currently accepted that life started locally on Earth.

  8. Discovering how to make 'synthetic nitrogen' became life's ...

    www.aol.com/news/discovering-synthetic-nitrogen...

    Carbon, nitrogen, and oxygen. None is more important than the other but if there's a first among equals it would be nitrogen. Discovering how to make 'synthetic nitrogen' became life's massive ...

  9. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Under low oxygen concentrations and before the evolution of nitrogen fixation, biologically-available nitrogen compounds were in limited supply, [16] and periodic "nitrogen crises" could render the ocean inhospitable to life. [9] Significant concentrations of oxygen were just one of the prerequisites for the evolution of complex life. [9]