Photosynthesis general scheme

The general scheme (I) for photosynthesis suggests directly the possibility of replacing the expensive fertilizers by mineral and organic pollutants. Additionnal CO2 released from industries may be used to increase the biomass yield. Solar energy is stored into the chemical bonds... 

The process of photosynthesis is generally explained by the modified Z-scheme [122-127]. Peso in PS II absorbs light and goes to an excited state. It releases an electron to a primary acceptor named pheophyhn. P eso thus formed receives electrons successively from a... 

Hill s hypothesis on photosynthetic electron transport from water to NADP has been a landmark in photosynthesis research [3], and has inspired all subsequent work in the field. The Z scheme originally proposed by Hill, in its present version (Fig. 1) has received experimental support from a very large number of differently conceived experiments performed with a variety of techniques and approaches, so as to be generally accepted by most scientists. However, Arnon et al. [4] have proposed a different hypothesis which will be briefly discussed in Section 2. 

However, even if not generally accepted, the scheme proposed by Calvin is of interest. The first stage of photosynthesis, is the conversion of water into a reducing substance and half a molecule of oxygen ... 

Fig. 6.15 In plant photosynthesis, light-induced electron transfer processes lead to the oxidation of water to O2 and the reduction of NADP+ to NADPH, with concomitant production of ATP. The energy stored in ATP and NADPH is used to reduce CO2 to carbohydrate in a separate set of reactions. The scheme summarizes the general patterns of electron flow and does not show aU the intermediate electron carriers in photosystems 1 and 11, the cytochrome b f complex, andferredoxin NADP oxidoreductase.

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