The history of the Earth goes back more than 4.5 billion years. Life began to develop the ability to absorb oxygen , that is, to breathe, more than 1.45 billion years ago: a larger archaeon absorbed a smaller bacterium, and somehow this union turned out to be beneficial for both, writes Science Alert.
This symbiotic relationship subsequently led to the two organisms evolving together. Eventually, the bacteria that settled inside became organelles known as mitochondria. In fact, every cell in our body, with the exception of red blood cells, contains a large number of mitochondria, which we need for respiration. It is the mitochondria that break down oxygen to produce the molecule adenosine triphosphate, which multicellular organisms use to power cellular processes...<<<Read More>>>...