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Archaebacteria
Archaebacteria Sub-kingdom of the kingdom Prokaryote, which, on the basis of both RNA and DNA composition and biochemistry, differs significantly from other bacteria. They are thought to resemble ancient bacteria that first arose in extreme environments such as sulphur-rich, deep-sea vents. Archaebacteria have unique protein-like cell walls and cell membrane chemistry, and distinctive ribosomes. They include methane-producing bacteria, which use simple organic compounds such as methanol and acetate as food, combining them with carbon dioxide and hydrogen gas from the air, and releasing methane as a by-product. The bacteria of hot springs and saline areas have a variety of ways of obtaining food and energy, including the use of minerals instead of organic compounds. They include both aerobic and anaerobic bacteria. Some hot springs bacteria can tolerate temperatures up to 88°C (190°F) and acidities as low as pH 0.9. One species, Thermoplasma, may be related to the ancestor of the nucleus and cytoplasm of the more advanced eukaryote cells. Some taxonomists consider archaebacteria to be so different from other living organisms that they constitute a higher grouping called a domain. See also taxonomy
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"Archaebacteria." World Encyclopedia. 2005. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. "Archaebacteria." World Encyclopedia. 2005. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O142-Archaebacteria.html "Archaebacteria." World Encyclopedia. 2005. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-Archaebacteria.html |
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Archaebacteria
Archaebacteria (är´kēbăktĬr´ēə), diverse group of bacteria (prokaryotes), sometimes called the archaea and considered a major group unto themselves. Archaebacteria are contrasted with the Eubacteria, from which they differ biochemically in the arrangement of the bases in their ribosomal RNA and in the composition of their plasma membranes and cell walls. There are three major known groups of Archaebacteria: methanogens, halophiles, and thermophiles. The methanogens are anaerobic bacteria that produce methane. They are found in sewage treatment plants, bogs, and the intestinal tracts of ruminants. Ancient methanogens are the source of natural gas. Halophiles are bacteria that thrive in high salt concentrations such as those found in salt lakes or pools of sea water. Thermophiles are the heat-loving bacteria found near hydrothermal vents and hot springs. Many thermophiles are chemosynthetic (see chemosynthesis), using dissolved sulfur or other elements as their energy source and iron as a means of respiration. Archaebacteria emerged at least 3.5 billion years ago and live in environments that resemble conditions existing when the earth was young. |
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"Archaebacteria." The Columbia Encyclopedia, 6th ed.. 2013. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. "Archaebacteria." The Columbia Encyclopedia, 6th ed.. 2013. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1E1-Archaea.html "Archaebacteria." The Columbia Encyclopedia, 6th ed.. 2013. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-Archaea.html |
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archaebacteria
archaebacteria (domain Archaea) Organisms belonging to the kingdoms Crenarchaeota and Euryarchaeota; formerly these were grouped together as the kingdom Archaebacteria.
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AILSA ALLABY and MICHAEL ALLABY. "archaebacteria." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "archaebacteria." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O13-archaebacteria.html AILSA ALLABY and MICHAEL ALLABY. "archaebacteria." A Dictionary of Earth Sciences. 1999. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-archaebacteria.html |
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archaebacteria
archaebacteria (domain Archaea) Organisms belonging to the kingdoms Crenarchaeota and Euryarchaeota; formerly these were grouped together as the kingdom Archaebacteria.
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MICHAEL ALLABY. "archaebacteria." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. MICHAEL ALLABY. "archaebacteria." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O7-archaebacteria.html MICHAEL ALLABY. "archaebacteria." A Dictionary of Plant Sciences. 1998. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-archaebacteria.html |
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archaebacteria
archaebacteria (domain Archaea) Organisms belonging to the kingdoms Crenarchaeota and Euryarchaeota; formerly these were grouped together as the kingdom Archaebacteria.
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Cite this article
MICHAEL ALLABY. "archaebacteria." A Dictionary of Zoology. 1999. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. MICHAEL ALLABY. "archaebacteria." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O8-archaebacteria.html MICHAEL ALLABY. "archaebacteria." A Dictionary of Zoology. 1999. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-archaebacteria.html |
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archaebacteria
archaebacteria(domain Archaea) Organisms belonging to the kingdoms Crenarchaeota and Euryarchaeota; formerly these were grouped together as the kingdom Archaebacteria.
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Cite this article
MICHAEL ALLABY. "archaebacteria." A Dictionary of Ecology. 2004. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. MICHAEL ALLABY. "archaebacteria." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O14-archaebacteria.html MICHAEL ALLABY. "archaebacteria." A Dictionary of Ecology. 2004. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-archaebacteria.html |
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archaebacteria
archaebacteria See Archaea.
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"archaebacteria." A Dictionary of Biology. 2004. Encyclopedia.com. 20 May. 2013 <http://www.encyclopedia.com>. "archaebacteria." A Dictionary of Biology. 2004. Encyclopedia.com. (May 20, 2013). http://www.encyclopedia.com/doc/1O6-archaebacteria.html "archaebacteria." A Dictionary of Biology. 2004. Retrieved May 20, 2013 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-archaebacteria.html |
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