A good example of endosymbiosis would be Professor Kwang Jeons' observation of amoebas and bacteria. Professor Kwang Jeon discovered that the surviving amoebas, and their offspring, couldn't survive without the bacteria. This is similar to the endosymbiotic theory. The host cell and the bacteria cell it ingested developed a beneficial existence. Overtime they lost the ability to live without each .This shows how cells become dependent on ingested, or invading cells.