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  2. Emerson effect - Wikipedia

    en.wikipedia.org/wiki/Emerson_effect

    When Emerson exposed green plants to differing wavelengths of light, he noticed that at wavelengths of greater than 680 nm the efficiency of photosynthesis decreased abruptly despite the fact that this is a region of the spectrum where chlorophyll still absorbs light (chlorophyll is the green pigment in plants - it absorbs mainly the red and blue wavelengths from light).

  3. Photochemical action plots - Wikipedia

    en.wikipedia.org/wiki/Photochemical_action_plots

    Photochemical action plots are a scientific tool used to understand the effects of different wavelengths of light on photochemical reactions.The methodology involves exposing a reaction solution to the same number of photons at varying monochromatic wavelengths, monitoring the conversion or reaction yield of starting materials and/or reaction products.

  4. Photosynthetic reaction centre - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_reaction_centre

    Photosystem II is present on the thylakoid membranes inside chloroplasts, the site of photosynthesis in green plants. [9] The structure of Photosystem II is remarkably similar to the bacterial reaction center, and it is theorized that they share a common ancestor. The core of Photosystem II consists of two subunits referred to as D1 and D2 ...

  5. Light-dependent reactions - Wikipedia

    en.wikipedia.org/wiki/Light-dependent_reactions

    Light-dependent reactions of photosynthesis at the thylakoid membrane. Light-dependent reactions are certain photochemical reactions involved in photosynthesis, the main process by which plants acquire energy. There are two light dependent reactions: the first occurs at photosystem II (PSII) and the second occurs at photosystem I (PSI).

  6. Photosynthetic efficiency - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_efficiency

    Using longer wavelengths means less light energy is needed for the same number of photons and therefore for the same amount of photosynthesis. For actual sunlight, where only 45% of the light is in the photosynthetically active wavelength range, the theoretical maximum efficiency of solar energy conversion is approximately 11%.

  7. Photosynthetically active radiation - Wikipedia

    en.wikipedia.org/wiki/Photosynthetically_active...

    However, photosynthesis is a quantum process and the chemical reactions of photosynthesis are more dependent on the number of photons than the energy contained in the photons. Therefore, plant biologists often quantify PAR using the number of photons in the 400-700 nm range received by a surface for a specified amount of time, or the ...

  8. Photochemistry - Wikipedia

    en.wikipedia.org/wiki/Photochemistry

    Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible (400–750 nm), or infrared radiation (750–2500 nm). [1] In nature, photochemistry is of immense importance as it is the basis of photosynthesis, vision, and the formation of vitamin D with sunlight. [2]

  9. PI curve - Wikipedia

    en.wikipedia.org/wiki/PI_Curve

    The PI (or photosynthesis-irradiance) curve is a graphical representation of the empirical relationship between solar irradiance and photosynthesis. A derivation of the Michaelis–Menten curve, it shows the generally positive correlation between light intensity and photosynthetic rate. It is a plot of photosynthetic rate as a function of light ...