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18.7: Photosynthesis

  • Page ID
    3419
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    Photoautotrophs use sunlight as a source of energy and through the process of photosynthesis, reduce carbon dioxide to form carbohydrates such as glucose. The radiant energy is converted to the chemical bond energy within glucose and other organic molecules. Plants, algae, and cyanobacteria are known as oxygenic photoautotrophs because they synthesize organic molecules from inorganic materials, convert light energy into chemical energy, use water as an electron source, and generate oxygen as an end product of photosynthesis. The overall reaction for photosynthesis is as follows:

    \[ 6 CO_2 + 12 H_2O \xrightarrow[\text{light}]{\text{chlorophyll}} C_6H_{12}O_6 + 6 O_2 + 6 H_2O\]

    Note that photosyntehsis is a redox reaction with carbon dioxide (\(CO_2\)) reduced to produce glucose (\(C_6H_{12}O_6\)) and water (\(H_2O\)) oxidized to produce oxygen (\(O_2\)). Photosynthesis is composed of two stages: the light-dependent reactions and the light independent reactions.


    This page titled 18.7: Photosynthesis is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Gary Kaiser via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.