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  2. Photosynthetic efficiency - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_efficiency

    Photosynthesis is the only process that allows the conversion of atmospheric carbon (CO2) to organic (solid) carbon, and this process plays an essential role in climate models. This lead researchers to study the sun-induced chlorophyll fluorescence (i.e., chlorophyll fluorescence that uses the Sun as illumination source; the glow of a plant) as ...

  3. Fractionation of carbon isotopes in oxygenic photosynthesis

    en.wikipedia.org/wiki/Fractionation_of_carbon...

    A simplified model of a chemical reaction with pathways for a light isotope (H) and heavy isotope (D) of hydrogen. The same principle applies for the light isotope 12 C and heavy isotope 13 C of carbon. The positions on the energy wells are based on the quantum harmonic oscillator. Note the lower energy state of the heavier isotope and the ...

  4. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    Photosynthesis (/ ˌ f oʊ t ə ˈ s ɪ n θ ə s ɪ s / FOH-tə-SINTH-ə-sis) [1] is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism.

  5. Light-dependent reactions - Wikipedia

    en.wikipedia.org/wiki/Light-dependent_reactions

    This is the second core process in photosynthesis. The initial stages occur within picoseconds, with an efficiency of 100%. The seemingly impossible efficiency is due to the precise positioning of molecules within the reaction center. This is a solid-state process, not a typical chemical reaction. It occurs within an essentially crystalline ...

  6. Oxygen-evolving complex - Wikipedia

    en.wikipedia.org/wiki/Oxygen-evolving_complex

    Photons trapped by photosystem II move the system from state S 0 to S 1 to S 2 to S 3 and finally to S 4. S 4 reacts with water producing free oxygen: 2 H 2 O → O 2 + 4 H + + 4 e −. This conversion resets the catalyst to the S 0 state. The active site of the OEC consists of a cluster of manganese and calcium with the formula Mn 4 Ca 1 O x ...

  7. Photosynthetic reaction centre - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_reaction_centre

    The charges on the P + and the BPh − could undergo charge recombination in this state, which would waste the energy and convert it into heat. Several factors of the reaction center structure serve to prevent this. First, the transfer of an electron from BPh − to P960 + is relatively slow compared to two other redox reactions in the reaction ...

  8. Photochemistry - Wikipedia

    en.wikipedia.org/wiki/Photochemistry

    Photoexcitation is the first step in a photochemical process where the reactant is elevated to a state of higher energy, an excited state.The first law of photochemistry, known as the Grotthuss–Draper law (for chemists Theodor Grotthuss and John W. Draper), states that light must be absorbed by a chemical substance in order for a photochemical reaction to take place.

  9. Photosystem II - Wikipedia

    en.wikipedia.org/wiki/Photosystem_II

    DCMU is a chemical often used in laboratory settings to inhibit photosynthesis. When present, DCMU inhibits electron flow from photosystem II to plastoquinone. When present, DCMU inhibits electron flow from photosystem II to plastoquinone.