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| | margulis |
 | | According to the traditional view, evolution usually occurs gradually; endosymbiosis, however, is based on the idea of rather sudden evolutionary changes. | | | Even those who strongly disagreed with her did not ridicule her theory the way biologists had belittled Ivan Wallin's theory about the evolution of mitochondria. | | | She also had to overcome a basic assumption about evolution held by nearly all biologists at the time. |
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http://www.msu.edu/course/lbs/145/luckie/margulis.html
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| | The Serial Endosymbiosis Theory of Eukaryotic Evolution |
| | The term "endosymbiosis" specifies the relationship between organisms which live one within another (symbiont within host) in a mutually beneficial relationship. | | | These three lines of evidence have been cited to firmly establish the theory of the origin of mitochondria and chloroplasts through the process of endosymbiosis. | | | ecent research by Martin and Müller (1998) into the origin of the mitochondrion has led to a new theory of endosymbiosis called the "hydrogen hypothesis." In the current picture of the origin of the eukaryotic cell, the mitochondrion was a "lucky accident" (Vogel 1998). |
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http://www.geocities.com/jjmohn/endosymbiosis.htm
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| | Brainstorms: Endosymbiosis and science |
| | Since endosymbiosis is a common phenomena, how does this square with a "single endosymbiotic origin of mitochondria?" It would seem to me that a polyphyletic origin follows more naturally from the basic tenets of the serial endosymbiosis thesis. | | | According to Margulis, his evidence "was based on the size, shape, staining properties and general cytological behavior or the organelles which he claimed were comparable to bacteria." In other words, Wallin drew up a list of similarities which seems awfully much like some form of argument from analogy. | | | ISCID Forums » General » Brainstorms » Endosymbiosis and science |
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http://www.iscid.org/boards/ubb-get_topic-f-6-t-000236.html
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| | Journal of Systematic Biology--Volume 8, Number 2 |
| | The third theory of serial endosymbiosis relies on symbiogenesis, or long term symbiotic relationships between different species that lead to new forms of life. | | | Each theory differs in the mechanism of organelle evolution, but we feel that the serial endosymbiosis theory (SET) is the most plausible. | | | Direct filiation is the classical view of the evolution of eukaryotic organisms. |
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http://comenius.susqu.edu/bi/202/Journal/Vol8/number2/dragonfliespub.htm
(1539 words)
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| | Endosymbiosis |
| | Everything the Earth is today and everything we and other living forms do today is due to conditions that have been created and maintained by bacteria. | | | Experiments by the Korean biologist Kwang Jeon showed that even virulent pathogens can become organelles. | | | That force may be hidden in the process of endosymbiosis, the process by which a new organism originates from the fusion of two existing organisms, or, more precisely, by which two independently evolved organisms become a tightly coupled system and eventually just one organism. |
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http://www.thymos.com/science/endosymb.html
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| | Protozoa - Consortia & Serial Endosymbiosis |
| | This serial endosymbiosis theory* for the origin of eukaryotic organelles gains much support from the ease with which protozoa can be seen to enter into symbiotic* relationships with bacteria. | | | With the transfer of genes from the symbiont's nucleus to that of the host, the relationship becomes obligate and the symbiont becomes an organelle - no longer capable of independent existence. |
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http://www-biol.paisley.ac.uk/courses/tatner/biomedia/units/prot8.htm
(100 words)
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| | SET and Organelles |
| | Because of commentary and criticism from Max Taylor and other generous colleagues the serial endosymbiosis theory prevailed. | | | Eventually the pain of the Academic Press rejection subsided. | | | Endosymbiosis = concept in biology in which one or more organisms lives inside another organism |
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http://www.lionden.com/set_and_organelles.htm
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| | Symbiosis |
| | A large body of evidence supports the view that intracellular symbiotic relationships gave rise to eukaryotes with their mitochondria and chloroplasts. | | | Examine some of the evidence at Endosymbiosis and The Origin of Eukaryotes |
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http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Symbiosis.html
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| | Eukaryotes |
| | Endosymbiosis is undoubtedly a fascinating concept and, at first glance, the evidence appears to support it as the mechanism for the evolution of chloroplasts and mitochondria. | | | The size of ribosomes in organelles varies among eukaryotes (60-80S) and while that does overlap with prokaryotic ribosomes (70S for eubacteria) it also overlaps with the cytoplasmic ribosomes of eukaryotes (78-80S). | | | Furthermore, most of the mitochondrial genes can also be found in the nucleus (endosymbiosis proponents explain this as leaping genes). |
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http://www.gwu.edu/~darwin/BiSc151/Eukaryotes/Eukaryotes.html
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| | Genome Biology Full text Phylogenomic evidence supports past endosymbiosis, intracellular and horizontal gene ... |
| | Our data, especially the analysis of G6PI and BT-1 are consistent with both primary and secondary endosymbioses, provided that the secondary endosymbiosis is pre-alveolate in origin. | | | Among the alveolates, plastids are found in dinoflagellates and most examined apicomplexans but not in ciliates. | | | The apicoplast is a relict plastid hypothesized to have been acquired by an ancient secondary endosymbiosis of a pre-alveolate eukaryotic cell with an algal cell [8]. |
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http://genomebiology.com/2004/5/11/R88
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| | Endosymbiosis |
| | Chloroplasts and mitochondrion evolved through a form of endosymbiosis. | | | According to one theory that is widely supported, mitochodrion evolved from small heterotrophic prokaryotes that were engulfed by a larger eukaryotic cells (where membrane infolding had occurred). | | | Symbiosis is an association between two or more species, and endosymbiosis implies that one species was living inside the other one, the host. |
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http://www.sidwell.edu/us/science/vlb5/Labs/Classification_Lab/Bacteria/symbiosis.html
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| | Profiles of microorganisms: the microbial world |
| | For further discussion of all these points, see: | | | One way in which this could have happened is by engulfment of one organism by another (perhaps followed by endosymbiosis), then some of the engulfed organism's genes might have been retained while others were lost over time. | | | Instead, there is likely to have been one or more gene transfer events between the evolving lines of bacteria, archaea and eucarya. |
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http://helios.bto.ed.ac.uk/bto/microbes
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| | Algae--Chapter 7 |
| | secondary endosymbiosis, and dinoflagellates as exemplars of tertiary | | | endosymbiosis, chlorarachniophytes as examples of a group that originated by | | | Endosymbiosis and the Origin of Eukaryotic Algae with a focus on Glaucophytes, Chlorarachniophytes, and Apicomplexans |
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http://www.botany.wisc.edu/cryptogams/graham/chapter7.html
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| | Endosymbiosis - The Appearance of the Eukaryotes |
| | This is the so-called serial endosymbiosis theory of a monophyletic origin of the mitochondrion from a eubacterial ancestor. | | | That fact that mitochondria have their own DNA, RNA, and ribosomes, supports the endosymbiosis theory, as does the existence of the amoeba, a eukaryotic organism that lacks mitochondria and therefore requires a symbiotic relationship with an aerobic bacterium. | | | Chloroplasts in plants and mitochondrion in other eukaryotes are believed to have evolved through a form of endosymbiosis. |
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http://www.fossilmuseum.net/Evolution/Endosymbiosis.htm
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| | ENDOSYMBIOTIC THEORY |
| | If the theory of endosymbiosis is true, then one must ask what was the original eukaryotic cell (without mitochondria or chloroplasts) and how did it survive (glycolysis?). | | | Alternate theories of the evolution of eukaryotic cells. | | | Simply stated, the theory of endosymbiosis is the concept that mitochondria and chloroplasts are the result of years of evolution initiated by the endocytosis of bacteria and blue-green algae which, instead of becoming digested, became symbiotic. |
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http://www.mrs.umn.edu/~goochv/CellBio/lectures/endo/endo.html
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| | Comment on "The Evolution of Modern Eukaryotic Phytoplankton" -- Keeling et al. 306 (5705): 2191b -- Science |
| | The most important of these groups is the apicomplexa, but we also show that tertiary endosymbiosis has occurred between dinoflagellates and diatoms (Kryptoperidinium) as well as cryptomonads and haptophytes. | | | Plastids have apparently been lost in ciliates and Cryptosporidium (and perhaps other lineages), and photosynthesis has been lost in apicomplexa and many other individual lineages. | | | This endosymbiont was reduced and integrated, and part of this process involved the transfer of hundreds of genes from the cyanobacterium/plastid to the eukaryotic host nucleus (red arrow). |
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http://www.sciencemag.org/cgi/content/short/306/5705/2191b
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| | Science Forums and Debate - Case for future endosymbiosis. |
| | Endosymbiosis, the theory that says that plastids such as mitochondria and chloraplasts are actually the decendents of bacteria that entered into a symbiotic relationship with other cells. | | | So what we have is a possible case for future endosymbiosis. | | | How easy might this be to overlook if you were researching some other aspect of the plant? |
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http://www.scienceforums.net/forums/printthread.php?t=7303
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| | Darwinism Refuted.com |
| | While the situation envisioned by the endosymbiosis hypothesis is occurring through a process of trial and error, what effects would this have on the DNA of the parent cell? | | | As we have seen, any change in a DNA molecule definitely does not result in a gain for that organism; on the contrary, any such mutation would certainly be harmful. | | | 331 The most popular of these is the "endosymbiosis" hypothesis. |
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http://www.darwinismrefuted.com/origin_of_plants_02.html
(1011 words)
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| | Symbiosis - Open Encyclopedia |
| | Symbiosis as defined in this article does not restrict the term to only the mutually beneficial interactions. | | | She considers Darwin's notion of evolution, driven by competition, as incomplete, and claims evolution is strongly based on co-operation, interaction, and mutual dependence among organisms. | | | Symbiosis may be divided into two distinct categories: ectosymbiosis and endosymbiosis. |
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http://open-encyclopedia.com/Symbiosis
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| | BioMed Central Full text A genomic timescale for the origin of eukaryotes |
| | This result was consistent with the serial endosymbiosis theory [3] and with other findings [6] and therefore we designated this divergence as BK-o (origin of eukaryotes). | | | Based on the serial endosymbiosis theory, the first symbiotic event involved a spirochete [3]. | | | On the other hand, sequence signatures of the heat shock molecular chaperone protein HSP-70 and other evidence have indicated that the first symbiotic event involved a gram-negative eubacterium [6]. |
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http://www.biomedcentral.com/1471-2148/1/4
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| | Sex and Nuclei: Eukaryotes |
| | Dinoflagellate Have a Diversity of Plastids from Secondary Endosymbiosis |
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http://biology.fullerton.edu/life/hol/hol_ch3.html
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| | 120lects4a |
| | The endosymbiosis theory was first proposed in 1918, but its acceptance owes to the efforts of | | | among eukaryotes and gram-negative bacteria suggest endosymbiosis as a possible mechanism. |
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http://bioweb.wku.edu/Courses/Biol120/McElroy/120lects5a.htm
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| | The theory of endosymbiosis |
| | Coursework and Essays: By Subject: Biology: The theory of endosymbiosi | | | Below is a short sample of the essay "The theory of endosymbiosis". | | | If you sign up you could be reading the rest of this essay in under two minutes. |
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http://www.coursework.info/i/14233.html
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| | endosymbiosis Free Essays |
| | Symbiotic Planet Review In Symbiotic Planet, author Lynn Margulis explains her Serial Endosymbiosis theory, which is a recent theory of how evolution occurred. | | | While the book was rather dull at times the theory itself is very intriguing. | | | Chlorophyll, which gives plants their green color, enables them to use sunlight to convert wa... |
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http://www.mytermpapers.com/search/56532.html
(74 words)
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| | Mysterious microbe retrofits itself with plant - Science - MSNBC.com |
| | They said the newly discovered organism seems to be in the process of endosymbiosis — in which one creature incorporates another, creating a new form of life. | | | WASHINGTON - A one-celled creature found on a sandy beach may be in the process of kidnapping and incorporating an even tinier plant to use as a living energy source, Japanese researchers reported Thursday. | | | Scientists believe this is how many modern plants and animals evolved. |
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http://www.msnbc.msn.com/id/9686843
(539 words)
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| | Botany online: Evolution - Energy-Conversion - Eucaryotes |
| | Phagocytosis may in some cases not have resulted in the digestion of the smaller cells, but in a symbiosis with them, a state also known as endosymbiosis. | | | The ability of large and cell wall-less eucaryotic cells to take up organic material led also to their taking up smaller cells, a process called phagocytosis. | | | According to the today mostly accepted endosymbiontic theory, primitive amoeboid eucaryotic cells took up aerobic bacteria as symbionts. |
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http://www.biologie.uni-hamburg.de/b-online/e42/42c.htm
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| | Endosymbiosis and The Origin of Eukaryotes |
| | However, a growing body of evidence indicates that the chloroplasts of some algae have not been derived by engulfing cyanobacteria (prokaryotes) in a primary endosymbiosis like those discussed above, but by engulfing photosynthetic eukaryotes. | | | Over time, the nucleus was lost (no residual nucleomorph) as well as many features of the chloroplast (including its ability to perform photosynthesis). | | | Usually the partners in these mutualistic relationships can be grown separately. |
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http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/E/Endosymbiosis.html
(1344 words)
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| | Introduction to the Cyanobacteria |
| | This event is known as endosymbiosis, and is also the origin of the eukaryotic mitochondrion. | | | Sometime in the late Proterozoic, or in the early Cambrian, cyanobacteria began to take up residence within certain eukaryote cells, making food for the eukaryote host in return for a home. |
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http://www.ucmp.berkeley.edu/bacteria/cyanointro.html
(383 words)
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| | Palaeos Eukarya: References |
| | McFadden, GI (2001), Primary and secondary endosymbiosis and the origin of plastids. |
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http://www.palaeos.com/Eukarya/Lists/EuReferences/EuReferences.html
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| | Endosymbiotic Theory |
| | [Endosymbiosis = cells are engulfed, but not digested...cells live together is a mutually benefitting relationship, or symbiosis] |
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http://www.biology.iupui.edu/biocourses/N100/2k2endosymb.html
(767 words)
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| | Endosymbiosis: A Friend Within |
| | A hands on activity that can be used for review/reinforcement of the ecological principle of symbiosis. | | | This activity is a class activity that requires one class period of a mininium of fifty minutes to complete. | | | It gets them to question how endosymbiosis and symbiosis differ? |
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http://www.accessexcellence.org/AE/AEC/AEF/1995/everson_endosymbiosis.html
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| | History: Endosymbiosis, Page 2 of 2 |
| | It has become clear that symbiotic events have had a profound impact on the organization and complexity of many forms of life. | | | Phylogenetic analyses based on genetic sequences support the endosymbiosis hypothesis. |
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http://evolution.berkeley.edu/evosite/history/endosym2.shtml
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| | Prokaryotes: |
| | Secondary endosymbiosis explains origin of diverse algal groups | | | Seaweeds are large marine algae adapted to coastal environment (have a “body” analogous to land plants, contain gel forming polysaccharides) | | | Algae: Photosynthetic protists (Note that these can be distinguished based on different photosynthetic pigments, food storage products (do not need details)) |
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http://www.d.umn.edu/~vborden/1012/sept8.htm
(109 words)
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| | Endosymbiosis |
| | Genome Biology Full text Phylogenomic evidence supports past endosymbiosis,... | | | Endosymbiosis and genome evolution, Molecular Evolution Workshop at the MBL, Aug... | | | Type III secretion systems and the evolution of... |
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http://www.scienceoxygen.com/biology/82.html
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| | Major Groups of Procaryotes |
| | Cyanobacteria are thought to have given rise to eukaryotic chloroplasts during the evolutionary events of endosymbiosis. | | | The main storage product of the cyanobacteria is glycogen, and glycogen inclusions may be seen in the cytoplasm of the cells. | | | In biochemical detail, cyanobacteria are especially similar to the chloroplasts of red algae (Rhodophyta). |
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http://www.bact.wisc.edu/Bact303/MajorGroupsOfProkaryotes
(9208 words)
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| | Merriam-Webster Online |
| | For More Information on "endosymbiosis" go to Britannica.com | | | Get the Top 10 Search Results for "endosymbiosis" |
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http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=endosymbiosis
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| | untitled |
| | Organelle evolution by endosymbiosis - ancestral eukaryote coopted bacterial assistants |
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http://www.life.umd.edu/classroom/biol106h/L15/Biol106_L15.html
(410 words)
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| | Green Earth Foundation |
| | organelles, the sub-components of cells, which are probably the evolutionary descendants of monera (bacteria) that have been incorporated into cells by endosymbiosis, according to the microbiologist Lynn Margolis; |
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http://www.greenearthfound.org/expanding.html
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| | What'sNEW in Cosmic Ancestry, Jul-Oct 2004. by Brig Klyce |
| | Although many unexpected or unfamiliar genes are seeen, the only source they suggest for any genes not vertically inherited with retained function is transfer, usually following symbiosis. | | | reflects large-scale transfers of genes between genomes during establishment of the endosymbiosis," they write. | | | A team of 45 genetictsts identified almost 11,500 genes in 24 nuclear chromosomes, a plastid and the mitochondria. |
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http://www.panspermia.com/whatsne34.htm
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