Endosymbiosis theory

The nucleus evolves from the internal symbiosis of ancient organisms, the genome of eukaryotic cells is the product of gene annealing, eukaryotes are the species they phagocytose, and the Golgi and endoderm are derived from the inner membrane of the membrane.

It is a distinct function of how mitochondria and plastids have similar individual cellular respiration or photosynthetic functions, including unique DNA, cytoplasm and membrane, ribosome and tRNA, respectively.

The theory of internal symmetry suggests an explanation for the existence of certain cellular structures in eukaryotic cells. According to this theory, complex eukaryotic cells evolved from symbiotic relationships (normal life) between larger and smaller cells, starting from undigested diets or larger cell parasites. Although internal symbiosis (coexistence) is not uncommon in nature, this theory suggests that mitochondria and chloroplasts are derived from free organisms, modern eukaryotic cells basically live together in different cell types It is a community.

In 1981, Dr. Lynn Margulis contributed to the theory of internal symbiosis by publishing her work "Symbiosis at Cellular Evolution". According to her study, the origin of mitochondria is an independent organism that initially forms a symbiotic relationship with eukaryotic cells through internal symbiosis. This was the main support for internal symbiosis theory, making her the hero behind the internal symbiosis hypothesis. Margulis basically opposes the idea of ​​random mutation, which is thought to be the main cause of genetic variation in species. Instead, she believes that the symbiotic merger will play a greater role in creating a new genome and genetic diversity. She believes that DNA in the cytoplasm of the cell is not a mutation but a prokaryotic (bacterial) gene that became an organelle.

Multiple pieces of evidence support the theory of symbiosis symbiosis. Internal symbiosis was observed elsewhere in biology. Mitochondria and chloroplasts have interesting similarities in the structure, reproductive, biochemical, and genetic makeup of certain prokaryotes. The obvious fact that mitochondria and chloroplasts have their own genetic information supports this theory. Since almost all eukaryotes have specific mitochondria and only photosynthetic eukaryotes have chloroplasts it has been proposed that endogenous embryos develop twice consecutively. First, a heterotrophic prokaryote of aerobic (using oxygen) is taken up by a larger host cell. Over time, prokaryotes and hosts evolved together, and eventually became mitochondria. Next, photosynthetic prokaryotes are incorporated into cells containing mitochondria. Continuity Symbiosis