Photosynthesis efficiency

Plants (particularly seedlings, which cannot yet accomplish efficient photosynthesis), as well as some bacteria and algae, can use acetate as the only source of carbon for all the carbon compounds they produce. Although we saw that the TCA cycle can supply intermediates for some biosynthetic processes, the... 

C02 assimilation. The amount of C02 available for photosynthesis decreases with decreasing C02 partial pressure at higher elevations, but this effect is offset by the increase in diffusion speed at lower air pressure (Gale 1972, 1973). The lower temperature at higher altitudes, however, decreases diffusion speed, and therefore the temperature lapse rate of the particular mountain determines whether C02 availability decreases (dry-moist lapse rate) or stays relatively constant (very wet lapse rate) (Smith and Donahue 1991). The lower air pressure at altitude does not just decrease C02 partial pressure but also 02 partial pressure, which results in lower photorespiration rates and more efficient photosynthesis. When all these effects are modeled, photosynthetic rates generally decrease with altitude, unless the temperature lapse rate is very low (which could occur in extremely wet mountain ranges), but the photosynthetic limitation is much less than expected based on just the partial pressure decrease (Terashima et al. 1995 Smith and lohnson 2007). 

The approach for this system is the mimicry of the highly efficient photosynthesis process in biological systems, by which an antenna device collects the light energy before a series of exciton, energy, and electron transfers, which lead to the synthesis of the plant s fuel.70-73... 

The photosynthetically wasteful electron/hole recombination between P-bSO" and Qa occurs with a half time of =100 /its [180], Thus efficient photosynthesis re-... 

While in theory, given we (would) know the turnover rates and metal contents of the corresponding enzymes, the M/M -ratios required to balance the above reactions in either animals or plants can (could) be calculated, we are better off by now j ust considering that the organisms which can be analyzed now (as they exist plentifully) apparently keep these and other metabolic balances which depend upon metal ratios - otherwise they would not be here. If, e.g. Mg Mn (Mg being a highly abundant soil cation, and Mn the second-most abundant heavy metal after Fe) in soil matches the ratio required for efficient photosynthesis, there are still two conditions at least one of which must be fulfilled ... 

Concerning, e.g. a tree or some other terrestrial plant which obtains its metals from soil mainly, when the ratio in local soil is given, BCF values must be balanced also in order to get efficient photosynthesis - or the excess metal must be removed or stored in some way. In oxic ocean water Mg Mn exceeds the propeT value by many orders of magnitude (Mg 53 mmol/L Mn (total) some 0.4 nmol/L (Nozaki 1997), that is Mg Mn ratio >10 rather than about 5). SNA arguments concerning maintenance of some stable flow state and thus coupled supply of two parts of collective autocatalyst can be linked to relative complex stabilities. 

Aquatic microalgae are characterized by their efficient photosynthesis and their fast proliferation compared with terrestrial C3- and C -plants. Hence, microalgae can be considered as a candidate for biological catalyst in GO2 fixation. 

Since dissolved inorganic carbon, such as free CO2 and bicarbonate, acts as a sole carbon source in photoautotrophic growth of microalgae, the partial pressure of CO2 in the atmosphere or in the supplied gas mixture is an important factor for their growth. Studies on the mechanisms underlying the efficient photosynthesis of microalgae in air level CO concentration (L-COj, 0.036%) will be described. 

Sweetlove,L.J., Lytovchenko, A., Morgan, M, Nunes-Nesi, A., Taylor, N.L., Baxter, CJ., Eickmeier, I. Fernie, A.R. (2006). Mitochondrial Uncoupling Protein is Required for Efficient Photosynthesis. Proceedings of the National Academy of Science, Vol.103, No. 51, (December 2006), pp. 19587-1959Z... 

Tsuchihira, A., Hanba, Y.T., Kato, N., Doi, T., Kawazu, T. Maeshima, M. (2010) Effects of Overexpression of Radish Plasma Membrane Aquaporins on Water-Use Efficiency, Photosynthesis and Growth of Eucalyptus Trees. Tree Physiology, Vol.30, No.3, (March 2010), pp. 417-430. 

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