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  2. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.

  3. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    [15] [16] The Moon's gravitational pull stabilised Earth's fluctuating axis of rotation, setting up regular climatic conditions favoring abiogenesis. [17] 4404 Ma Evidence of the first liquid water on Earth which were found in the oldest known zircon crystals. [18] 4280–3770 Ma Earliest possible appearance of life on Earth. [19] [20] [21] [22]

  4. Timeline of plant evolution - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_plant_evolution

    The main Early Carboniferous plants were the Equisetales (Horse-tails), Sphenophyllales (scrambling plants), Lycopodiales (Club mosses), Lepidodendrales (arborescent clubmosses or scale trees), Filicales (Ferns), Medullosales (previously included in the "seed ferns", an artificial assemblage of a number of early gymnosperm groups) and the ...

  5. Nitrogen assimilation - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_assimilation

    Nitrogen assimilation is the formation of organic nitrogen compounds like amino acids from inorganic nitrogen compounds present in the environment. Organisms like plants, fungi and certain bacteria that can fix nitrogen gas (N 2) depend on the ability to assimilate nitrate or ammonia for their needs. Other organisms, like animals, depend ...

  6. Evolutionary history of plants - Wikipedia

    en.wikipedia.org/wiki/Evolutionary_history_of_plants

    Land plants evolved from a group of freshwater green algae, perhaps as early as 850 mya, [3] but algae-like plants might have evolved as early as 1 billion years ago. [2] The closest living relatives of land plants are the charophytes, specifically Charales; if modern Charales are similar to the distant ancestors they share with land plants, this means that the land plants evolved from a ...

  7. Evolution of photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_photosynthesis

    The C 4 metabolic pathway is a valuable recent evolutionary innovation in plants, involving a complex set of adaptive changes to physiology and gene expression patterns. [25] About 7600 species of plants use C 4 carbon fixation, which represents about 3% of all terrestrial species of plants. All these 7600 species are angiosperms.

  8. 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 ...

  9. Actinorhizal plant - Wikipedia

    en.wikipedia.org/wiki/Actinorhizal_plant

    Evolutionary origin of nitrogen-fixing nodulation. No fossil records are available concerning nodules, but fossil pollen of plants similar to modern actinorhizal species has been found in sediments deposited 87 million years ago. The origin of the symbiotic association remains uncertain.