Lynn Margulis and the Question of How Cells Evolved Margulis wrote her first article on the endosymbiotic theory in , two years after she completed her. Lynn Margulis. Symbiosis in Cell Evolution. The theory maintains that ancestors of eukaryotic cells were. ” of prokaryote cells with at least one and possibly more . Lynn Margulis: Lynn Margulis, American biologist whose serial endosymbiotic theory of eukaryotic cell development revolutionized the modern.
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Margulis was raised in Chicago. Soon lyn, she married American astronomer Carl Saganwith whom she had two children; one, Dorion, would become her frequent collaborator.
The couple divorced in She joined the biology department of Boston University in and taught there endosymbiotocwhen she was named distinguished university professor in the department of botany at the University of Massachusetts at Amherst. She retained that title when her affiliation at the university changed to the department of biology in and then to the department of endosymhiotic in Her ideas, which focused on symbiosis —a living arrangement of two different organisms in an association that can be either beneficial or unfavourable—were frequently greeted with skepticism and even hostility.
Among her most important work was the development of the serial endosymbiotic theory SET of the origin of cellswhich endosymbiktic that eukaryotic cells cells with nuclei evolved from the symbiotic merger of nonnucleated bacteria that had previously existed independently. In this theory, mitochondria and chloroplaststwo major organelles of eukaryotic cells, are descendants of once free-living bacterial species. She explained the concept in her first book, Origin of Eukaryotic Cells At the magulis, her theory was regarded as far-fetched, but it has since been widely accepted.
She elaborated endosymbiotix her endosymbioric, Symbiosis in Cell Evolutionproposing that another symbiotic merger of cells with bacteria—this time spirochetesa type of bacterium that undulates rapidly—developed into the internal transportation system of the nucleated cell.
Margulis further postulated that eukaryotic cilia were also originally spirochetes and that cytoplasm evolved from a symbiotic relationship between eubacteria and archaebacteria see archaea. Schwartz, articulates a five- kingdom system of classifying life on Earth— animalsplantsbacteria prokaryotesfungiand protoctists. The protist kingdom, which comprises most unicellular organisms and multicellular algae in other systems, is rejected as too general.
Many of the organisms usually categorized as protists are placed in one of the other four kingdoms; protoctists make up the remaining organisms, which are all aquatic, and include algae and slime molds.
Margulis edited portions of the compendium Handbook of Protoctista Another area of interest for Margulis was her long collaboration with British scientist James Lovelock on the controversial Gaia hypothesis. This proposes that the Earth can be viewed as a single self-regulating organism—that is, a complex entity whose living and inorganic elements are interdependent and whose life-forms actively modify the environment to maintain hospitable conditions.
Among them were Mystery Dance: Reflections on Nature in Natureall cowritten with her son.
Lynn Margulis and the endosymbiont hypothesis: 50 years later
She also wrote a book margulos stories, Luminous Fish Her later efforts were published under the Sciencewriters Books imprint of Chelsea Green Publishing, which she cofounded with Dorion in National Medal of Science in magulis We welcome suggested improvements to any of our articles. You can make it easier for us to review and, hopefully, publish your contribution by keeping a few points in mind. Your contribution may be further edited by our staff, and its publication is subject to our final approval.
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Lynn Margulis | American biologist |
Our editors will review what you’ve submitted, margulos if it meets our criteria, we’ll add it to the article. Please note that our editors may make some formatting changes or correct spelling or grammatical errors, and may also contact you if any clarifications are needed. Nov 18, See Article History. Amy Tao Learn More in these related Britannica articles: Eukaryoteany cell or organism that possesses a clearly defined nucleus.
The eukaryotic cell has a nuclear membrane that surrounds the nucleus, in which the well-defined chromosomes bodies containing the hereditary material are located. Eukaryotic cells also contain organelles, including mitochondria cellular energy exchangersa Golgi apparatus secretory devicean…. Carl SaganAmerican astronomer and science writer. A popular and influential figure in the United States, he was controversial in scientific, political, and religious circles for his views on extraterrestrial intelligence, nuclear….
Symbiosisany of several living arrangements between members of two different species, including mutualism, commensalism, and parasitism qq.
Both positive beneficial and negative unfavourable to harmful associations are therefore included, and the members are called symbionts. Chicago, city, seat of Cook county, northeastern Illinois, U. In addition, the greater Chicagoland area—which encompasses northeastern Illinois and extends into southeastern…. Massachusetts, constituent state of the United States of America.
It was one of the original 13 states endossymbiotic is one of the 6 New England states, lying in the northeastern corner of the country. Margulus officially called a commonwealth is bounded to the north by Vermont and New Hampshire, to…. Articles from Britannica Encyclopedias for elementary and high school students.
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