Dr Lynn Margulis, a biologist from Boston University, proposed in the 1960s, the theory of endo mutualism. It was so officially published in her book Symbiosis in Cell Evolution. The theory suggests that cells originated as communities of interacting entities a could aggregate together in a specific order. Organelles same mitochondria and chloroplasts were themselves procaryotic cells before the development of eukaryotic cells. It was believed that a swarm cell, likely similar to amoeba, ingested a smaller cell by phagocytes. They ingested in a way that the forces cells are unable to withdraw them and they were allowed to survive. Also, the DNA of the ingested cell would be coded into the host cell which causes consequent generations they could also contain the ingested cell. Margulis also predicted if the organelles were really prokaryotic symbionts, they should sire their own DNA and also should resemble that of bacteria and antithetical from the hosts DNA. Mitoch ondria as aerophilic bacteria, chloroplasts as cyanobacteria... For mitochondria, they previously were like aerophilous bacteria and this takes place in an oxygenated environment. The host cell respires anaerobically ingested a cell which respires aerobically. Since more adenosine triphosphate could be produced by aerobic respiration, the host cell could now be provided with more ATP and in return, provide nutrients like glucose to the ingested cell. Similar for chloroplast, they were previously like cyanobacteria. They were ingested by an aerobic host, after being ingested, they continue to photosynthesise. As a result, they provide the host with oxygen and food like glucose and the host would provide the cells with carbon dioxide and nitrogen which are reactants for photosynthesis. This mutualistic interaction amongst the host and the ingested cell then became an obligatory symbiosis as the two sides lost some of their abilities to function without another. eukaryotic cells li ke... ! If you trust to get a full essay, order it on our website: BestEssayCheap.com
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