Aerobic respiration and oxidative phosphorylation

Phosphorylation linked to electron transport is the other major mechanism of generation of ATP in cells. Carbon substrates are completely oxidised in the presence of oxygen to carbon dioxide and reducing equivalents, the latter usually in the form of NADH. NADH is a source of electrons which are then used to generate via electron transport processes before they ultimately reduce oxygen to form water. This process is commonly called aerobic respiration. 

Respiration is a broad term for the oxidation of organic materials to carbon dioxide. When the electron acceptor is not oxygen they are called anaerobic respirations. Table S.I4 illustrates possible types of respiration. Nitrate, sulphate and carbon dioxide are significant electron acceptors in anaerobic respiration and many are of environmental significance. 

Aerobic respiration can be subdivided into a number of distinct but coupled processes, such as the carbon flow pathways resulting in the production of carbon dioxide and the oxidation of NADH + H+ and FADH2 (flavin adenine dinucleotide) to water via the electron transport systems or the respiratory chain. 

Organic compounds o2 COj + HjO Many bacteria, all plants and animals 

Glucose is converted to pyruvate by the glycolytic pathway (Fig. 5.20). Pyruvate is then oxidised to acetyl-CoA and C02 by the pyruvate decarboxylase enzyme  

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