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The Theory of Endosymbiosis . Evelyn Woodcock . Endosymbiosis is the theory that a larger host cell engulfed free-living cells and sustained a symbiotic relationship which co-evolved with the host cell into the mitochondria and chloroplasts. . The Theory.
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The Theory of Endosymbiosis Evelyn Woodcock
Endosymbiosis is the theory that a larger host cell engulfed free-living cells and sustained a symbiotic relationship which co-evolved with the host cell into the mitochondria and chloroplasts. The Theory
In some prokaryotic cells, the plasma membrane infolds. -These folds are thought to have formed the endoplasmic reticulum and encased the DNA within the cell forming the nuclear envelope • This would be an early prokaryote cell Host Cell
The mitochondria is thought to have originally been a proteobacterium with an oxidative metabolism which benefited the larger cell and also provided energy. Mitochondria
The chloroplasts are thought to have evolved from a cyanobacteria, a photosynthetic bacterium • Both of these prokaryotes would have benefited with a stable environment to thrive in within this cell Chloroplasts
Aside from all the symbiotic relationships we see today… • Mitochondria and chloroplasts have their own membranes • and their own DNA... • … and replicate through binary fission • They also react to antibiotics that inhibit protein synthesizers What evidence?
Before biologist Lynn Margulis, organelles in cells seemed so complex, and were without explanation. • First proposed by Konstantin Mereschkowski in 1905, the theory of endosymbiosis is now widely accepted.
Mason, Kenneth A., Jonathan B. Losos, Susan R. Singer, Peter H. Raven, and George B. Johnson. "4.5, 29.1." Biology: Evolution, Diversity and Ecology: Selected Materials from Biology, 10th Edition. 10th ed. New York: McGraw-Hill, 2014. N. pag. Print. Mikulecky, Peter, Michelle R. Gilman, and Brian Peterson. "Endosymbiotic Theory." - For Dummies. John Wiley & Sons, Inc, n.d. Web. 17 Mar. 2014. <http://www.dummies.com/how-to/content/endosymbiotic-theory.html>. Sources