Photosynthesis oxygen role

Except as an index of respiration, carbon dioxide is seldom considered in fermentations but plays important roles. Its participation in carbonate equilibria affects pH removal of carbon dioxide by photosynthesis can force the pH above 10 in dense, well-illuminated algal cultures. Several biochemical reactions involve carbon dioxide, so their kinetics and equilibrium concentrations are dependent on gas concentrations, and metabolic rates of associated reactions may also change. Attempts to increase oxygen transfer rates by elevating pressure to get more driving force sometimes encounter poor process performance that might oe attributed to excessive dissolved carbon dioxide. 

Colorless, reactive gas. Oxygen was not present in the initial atmosphere of the Earth, although at 50 % it is the most common element in the crust of the Earth (oxides, silicates, carbonates, etc.). The compound with hydrogen is remarkable. The hydrides of all other elements are unpleasant compounds, but H20 is the molecule of life. The 02 found in the air today, of which it makes up 20 %, was formed in the process of evolution by photosynthesis of algae, which then also allowed life on solid land. Oxidation with oxygen became and is still the dominant pathway of life forms for obtaining energy (respiration). Used in medicine in critical situations. Oxidations play a key role in chemistry (sulfuric acid, nitric acid, acetic acid, ethylene oxide, etc.). The ozone layer in space protects the Earth from cosmic UV radiation. Ozone (03) is used in the... 

In the course of evolution, the importance of particular metal ions in biological systems has ebbed and flowed, as a function of environmental conditions. Before the arrival of photosynthesis, when there was no oxygen, elements like Fe and Ni were extremely important, whereas, for example, Cu was virtually inaccessible for reasons of solubility. With the arrival of an oxidizing environment, Ni virtually disappeared from the equation, Cu became bioavailable, and Fe, although it was now insoluble and poorly available, had proved of such fundamental importance in biological catalysis that specific systems were developed for its uptake from the environment, such that it continues to play a key role in life as we know it today. 

Role of Trace Metals in the Evolution of Oxygenic Photosynthesis... 

Photosynthesis is the reduction of C02 by electrons from water with the help of visible irradiation producing carbohydrate and oxygen. The outline of the electrone flow is expressed by Fig. 1. The electron from water is pumped up twice by photosystems II and I (PS II and I), where chlorophyll (Chi) molecules play the main role for the excitation, energy concentration, and charge separation. 

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