In: Biology
Endosymboitic theory came up with two organelles such as mitochondria and chloroplasts. These two organelles later developed into part of eukaryotic organisms. These two organelles were originated as a separate prokaryotic organisms later they taken up by host cell or eukaryotes as endosymbionts.
Eukarytic cells which carried out anaerobic respiration by glycolysis where the energy production was not sufficient. Then the host cell started mutually beneficial relationship with the bacterium (endosymbionts) in which eukaryotes provieded protection and nutrients to the prokaryotes (endosymbionts) supplied additional energy to its eukaryotic hosts through its respiratory cellular apparatus.
In other words, host cell provided protecting environament and carbon compound to the prokaryotes and they provided increased ATP from the carbon compound in return.
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