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Kingdoms prokaryotes eubacteria archaebacteria

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Unformatted text preview: o being. Her theory suggests that maybe an oxygen breathing bacteria was eaten, or ingested, by an anaerobic bacteria that had amoeba-like features. These two bacteria features worked together, mutually benefiting from each other's functions. The aerobic bacteria breathed for the anaerobic bacteria, while the anaerobic bacteria directed them through the waters in a hunt for food. The Endosymbiotic Theory Lynn Margulies The Endosymbiotic Theory Lynn Margulies After the proposal of the endosymbiotic theory, Margulis predicted that if organelles were prokaryotic symbionts, then the organelles will have their own DNA that would be different from the DNA of the cell. cell This prediction was actually proven in the 1980's in mitochondria, centrioles, and chloroplasts. The Endosymbiotic Theory Lynn Margulies For many years, Margulis was criticized and ridiculed for her "radical" thinking. However, Margulis pursued onward, which lead to the general acceptance of her theory. users.rcn.com/jkimball.ma.ultranet/BiologyP ages/E/Endosymbiosis.html www.immaculata.edu/bioinformatics/ esehi/lynn%20margulis.htm The Endosymbiotic Theory Evidence Both mitochondria and chloroplasts can arise only from preexisting mitochondria and chloroplasts. They cannot be formed in a cell that lacks them because nuclear genes encode only some of the proteins of which they are made. The Endosymbiotic Theory Evidence Both mitochondria and chloroplasts have their own genome and it resembles that of prokaryotes not that of the nuclear genome. Both genomes consist of a single circular molecule of DNA. There are no histones associated with the DNA. The Endosymbiotic Theory Evidence Both mitochondria and chloroplasts have their own protein-synthesizing machinery, and it more closely resembles that of prokaryotes than that found in the cytoplasm of eukaryotes. The first amino acid of their transcripts is always fMet as it is in bacteria (not methionine [Met] that is the first amino acid in eukaryotic proteins). The Endo...
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This note was uploaded on 04/08/2008 for the course BIO 29 taught by Professor Mcgowan during the Spring '08 term at CUNY Brooklyn.

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