Synthesis Of Photosynthesis

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Photosynthetic organisms have the ability to convert solar energy into electrochemical energy. This creates a dynamic relationship between the organisms and the light that they absorb. Although light is required to drive photosynthesis, the photosynthetic machinery can only tolerate so much of it. Excess light may lead to the generation of reactive oxygen intermediates resulting in oxidative damage to the photosynthetic apparatus (Niyogi, 1999). Therefore it is necessary for organisms such as the green algae Chlamydomonas reinhardtii to employ photoprotective mechanisms in order to maintain photosynthetic efficiency and reduce stress caused by excess light. During photosynthesis, solar energy in the form of light is absorbed. This light drives charge separation in the reaction centres of photosystems I (PSI) and II (PSII), initiating electron transport which then leads to the oxidation of …show more content…

They are connected in series by an electron transport chain and they differ in the organization of light harvesting systems and pigment compositions. The two pigments found in the photosystems of green algae are chlorophylls and carotenoids (Green and Durnford, 1996). Chlorophyll is the principal pigment that functions to trap light energy and it is present in two forms; chlorophyll a (Chl a) and chlorophyll b (Chl b), and they can be distinguished based on their absorption spectra. Chl a has an absorption maxima of 659 nm and 429 nm while Chl b has an absorption maxima of 642 nm and 455 nm (Zscheile and Comar, 1941). The presence of two pigments with differing absorption maxima functions to broaden the range of light that can be absorbed and used for photosynthesis. Carotenoids are also present in the photosystems and in addition to serving as light harvesting apparatus, the carotenoids are involved in energy dissipation in the presence of excess light (Santabarbara et al.,

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