AP BIOLOGY

Detailed explanation-1: -7.2 Primary and Secondary Endosymbiosis. A symbiotic relationship where one organism lives inside the other is known as endosymbiosis. Primary endosymbiosis refers to the original internalization of prokaryotes by an ancestral eukaryotic cell, resulting in the formation of the mitochondria and chloroplasts.

Detailed explanation-2: -endosymbiosis. / (ˌɛndəʊˌsɪmbɪˈəʊsɪs) / noun. a type of symbiosis in which one organism lives inside the other, the two typically behaving as a single organism. It is believed to be the means by which such organelles as mitochondria and chloroplasts arose within eukaryotic cells.

Detailed explanation-3: -An endosymbiont or endobiont is any organism that lives within the body or cells of another organism most often, though not always, in a mutualistic relationship.

Detailed explanation-4: -The endosymbiotic theory states that some of the organelles in eukaryotic cells were once prokaryotic microbes. Mitochondria and chloroplasts are the same size as prokaryotic cells and divide by binary fission. Mitochondria and chloroplasts have their own DNA which is circular, not linear.

Detailed explanation-5: -We have identified the first human endosymbiont and generated a novel antibody which detects it. The existence of endosymbionts in human tissue is not readily apparent without the antibody, explaining why they have not been seen previously.