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prokaryote
prokaryote (formerly Monera) Any member of the biological kingdom (Prokaryotae); it includes bacteria and cyanobacteria (formerly blue-green algae). They have more simple cells than other organisms. DNA is not contained in chromosomes in the nucleus, but lies in a distinct part of the cytoplasm, called the nucleoid. They have no distinct membrane-surrounded structures (organelles). Cell division is simple and, in the rare cases where sexual reproduction occurs, genetic material is simply transferred from one partner to another; there are no separate sex cells. In photosynthetic prokaryotes, photosynthesis takes place on the cell membrane. At present, two subkingdoms are recognized: Archaebacteria and Eubacteria. See also asexual reproduction; eukaryote; symbiosis
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"prokaryote." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "prokaryote." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-prokaryote.html "prokaryote." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-prokaryote.html |
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prokaryote
prokaryote A type of organism that is mainly unicellular and in which the cells lack a true nucleus; in all known prokaryotes the DNA is present as a loop in the cytoplasm. Other prokaryotic features include the lack of chloroplasts and mitochondria and the possession of small ribosomes. The prokaryotes comprise two groups (domains): Eubacteria (the bacteria, including the cyanobacteria, formerly known as ‘blue-green algae’) and Archaea (see EXTREMOPHILES).
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MICHAEL ALLABY. "prokaryote." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "prokaryote." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O7-prokaryote.html MICHAEL ALLABY. "prokaryote." A Dictionary of Plant Sciences. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-prokaryote.html |
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prokaryote
pro·kar·y·ote / prōˈkarēˌōt/ (also pro·car·y·ote) • n. Biol. a microscopic single-celled organism, including the bacteria and cyanobacteria, that has neither a distinct nucleus with a membrane nor other specialized organelles. Compare with eukaryote. DERIVATIVES: pro·kar·y·ot·ic / prōˌkarēˈätik/ adj. |
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"prokaryote." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "prokaryote." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-prokaryote.html "prokaryote." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-prokaryote.html |
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prokaryote
prokaryote (procaryote) Any organism in which the genetic material is not enclosed in a cell nucleus. Prokaryotes consist exclusively of bacteria, i.e. archaebacteria and eubacteria, which some authorities place together in the kingdom Bacteria (or Prokaryotae); others classify them in separate domains. It is believed that eukaryotic cells (see eukaryote) probably evolved as symbiotic associations of prokaryotes (see endosymbiont theory).
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"prokaryote." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "prokaryote." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-prokaryote.html "prokaryote." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-prokaryote.html |
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prokaryote
prokaryote A single-celled organism in which the cell lacks a true nucleus and the DNA is present as a loop in the cytoplasm rather than as chromosomes bounded by a nuclear membrane. The prokaryotes comprise the bacteria, which appear in the fossil record more than 3000 Ma ago and are the oldest forms of life known, and the cyanobacteria, known from slightly younger rocks.
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MICHAEL ALLABY. "prokaryote." A Dictionary of Zoology. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "prokaryote." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O8-prokaryote.html MICHAEL ALLABY. "prokaryote." A Dictionary of Zoology. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-prokaryote.html |
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prokaryote
prokaryote An organism, usually unicellular, in which the cells lack a true nucleus, the DNA being present as a loop in the cytoplasm. Other prokaryotic features include the lack of chloroplasts and mitochondria and the possession of small ribosomes. Compare EUKARYOTE.
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AILSA ALLABY and MICHAEL ALLABY. "prokaryote." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "prokaryote." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-prokaryote.html AILSA ALLABY and MICHAEL ALLABY. "prokaryote." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-prokaryote.html |
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prokaryote
prokaryote An organism, usually unicellular, in which the cells lack a true nucleus, the DNA being present as a loop in the cytoplasm. Other prokaryotic features include the lack of chloroplasts and mitochondria and the possession of small ribosomes.
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MICHAEL ALLABY. "prokaryote." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "prokaryote." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-prokaryote.html MICHAEL ALLABY. "prokaryote." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-prokaryote.html |
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prokaryote
prokaryote see Monera . |
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"prokaryote." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "prokaryote." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-X-prokary.html "prokaryote." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-prokary.html |
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