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  2. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    Oxygenic photosynthesis is the main source of oxygen in the Earth's atmosphere, and its earliest appearance is sometimes referred to as the oxygen catastrophe. Geological evidence suggests that oxygenic photosynthesis, such as that in cyanobacteria , became important during the Paleoproterozoic era around two billion years ago.

  3. Energy flow (ecology) - Wikipedia

    en.wikipedia.org/wiki/Energy_flow_(ecology)

    A graphic representation of energy transfer between trophic layers in an ecosystem. Energy flow is the flow of energy through living things within an ecosystem. [1] All living organisms can be organized into producers and consumers, and those producers and consumers can further be organized into a food chain.

  4. Autotroph - Wikipedia

    en.wikipedia.org/wiki/Autotroph

    An autotroph is an organism that can convert abiotic sources of energy into energy stored in organic compounds, which can be used by other organisms. Autotrophs produce complex organic compounds (such as carbohydrates , fats , and proteins ) using carbon from simple substances such as carbon dioxide, [ 1 ] generally using energy from light or ...

  5. Plant - Wikipedia

    en.wikipedia.org/wiki/Plant

    The photosynthesis conducted by land plants and algae is the ultimate source of energy and organic material in nearly all ecosystems. Photosynthesis, at first by cyanobacteria and later by photosynthetic eukaryotes, radically changed the composition of the early Earth's anoxic atmosphere, which as a result is now 21% oxygen.

  6. Sun - Wikipedia

    en.wikipedia.org/wiki/Sun

    Sunlight on the surface of Earth is attenuated by Earth's atmosphere, so that less power arrives at the surface (closer to 1,000 W/m 2) in clear conditions when the Sun is near the zenith. [100] Sunlight at the top of Earth's atmosphere is composed (by total energy) of about 50% infrared light, 40% visible light, and 10% ultraviolet light. [101]

  7. Carbon-based life - Wikipedia

    en.wikipedia.org/wiki/Carbon-based_life

    Carbon is a primary component of all known life on Earth, and represents approximately 45–50% of all dry biomass. [1] Carbon compounds occur naturally in great abundance on Earth. Complex biological molecules consist of carbon atoms bonded with other elements , especially oxygen and hydrogen and frequently also nitrogen , phosphorus , and ...

  8. List of energy resources - Wikipedia

    en.wikipedia.org/wiki/List_of_energy_resources

    Energy portal; These are modes of energy production, energy storage, or energy conservation, listed alphabetically. Note that not all sources are accepted as legitimate or have been proven to be tappable. Bus running on soybean biodiesel. Atomic energy; Alternative fuel; Alternative fuel vehicle; Banki turbine; Battery (electricity) Bioalcohol ...

  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 ...