An aerobic organism or aerobe is an organism that has an oxygen based metabolism. Aerobes, in a process known as cellular respiration, use oxygen to oxidize substrates (for example sugars and fats) in order to obtain energy.Obligate aerobes require oxygen for aerobic cellular respiration.Facultative aerobes can use oxygen, but also have anaerobic methods of energy production. Microaerophiles are organisms that may use oxygen, but only at low concentrations.Aerotolerant organisms can survive in the presence of oxygen, but they are anaerobic because they do not use it as a terminal electron acceptor.
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