What are facultative anaerobes?
1 Answer
Anaerobes are organisms that can live without oxygen. Oxygen actually can kill them and they are called strict anaerobes . They can be seen in the second test tube.
Facultative anaerobes can live without oxygen if they have to and they can live in an oxygen rich environment. They have adapted to live in either world. These are seen in the third test tube,
Aerotolerant organisms, which cannot use oxygen for growth, but tolerate its presence are another type of microbe. They are seen in test tube number 5.
Anaerobes probably were the first microbes in that the Earth's atmosphere was low in oxygen.
It is thought the most ancient type of respiration is anaerobic. Since there was little to no oxygen present when the first eukaryotic cells evolved through endosymbiosis, they could only undergo anaerobic respiration or something similar to fermentation. This was not a problem, however, since those first cells were unicellular. Producing only 2 ATP at a time was enough to keep the single cell running.
