|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
eukaryote
eukaryote , a cell or organism composed of cells that have a membrane-bound nucleus and organelles (mitochondria, chloroplasts; see cell , in biology) and genetic material organized in chromosomes in which the DNA is combined with histone proteins. Eukaryotes are contrasted with the prokaryotes (see Monera ). Eukaryotes formed through the merger of prokaryotes, which predate them in the fossil record by some 2 billion years. In the five-kingdom system of classification , the eukaryotes have comprised the taxonomic kingdoms Protista , Fungi , Plantae (see plant ), and Animalia (see animal ). In a recently proposed system they are called the eukarya and classified as an overarching group (domain) above the kingdom level. |
|
|
Cite this article
"eukaryote." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "eukaryote." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-eukary.html "eukaryote." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-eukary.html |
|
eukaryote
eukaryote Organism whose cells have a membrane-bound nucleus, with DNA contained in chromosomes. Making up one of the three domains, eukaryotes include all animals, plants, fungus, and Protoctista. They have a complex cytoplasm with an endoplasmic reticulum, and most of them possess mitochondria. Most plants and algae also possess chloroplasts. Other structures specific to eukaryotic cells include microtubules, Golgi bodies, and membrane-bound flagella. See also Golgi body; kingdom; mitochondrion; prokaryote
|
|
|
Cite this article
"eukaryote." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "eukaryote." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-eukaryote.html "eukaryote." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-eukaryote.html |
|
eukaryote
eukaryote An organism whose cells have a distinct nucleus enveloped by a double membrane, and other features including double-membraned mitochondria and 80S ribosomes in the fluid of the cytoplasm (i.e. all protists, fungi, plants, and animals). The first eukaryotes were almost certainly green algae (Chlorophyceae) and what appear to be their microscopic remains appear in Proterozoic sediments dating from a little less than 1500 Ma ago.
|
|
|
Cite this article
MICHAEL ALLABY. "eukaryote." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "eukaryote." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-eukaryote.html MICHAEL ALLABY. "eukaryote." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-eukaryote.html |
|
eukaryote
eukaryote An organism comprising cells that have a distinct nucleus enveloped by a double membrane, and other features including double-membraned mitochondria and 80S ribosomes in the fluid of the cytoplasm (i.e. all protists, fungi, plants, and animals). The first eukaryotes were almost certainly green algae, and what appear to be their microscopic remains appear in Precambrian sediments dating from a little less than 1500 Ma ago.
|
|
|
Cite this article
MICHAEL ALLABY. "eukaryote." A Dictionary of Zoology. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "eukaryote." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O8-eukaryote.html MICHAEL ALLABY. "eukaryote." A Dictionary of Zoology. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-eukaryote.html |
|
eukaryote
eukaryote (adj. eukaryotic) Organism with cells that have a distinct nucleus, i.e. all protists, fungi, plants, and animals. The first eukaryotes were almost certainly green algae (Chlorophyta), and what appear to be their microscopic remains appear in Precambrian sediments dating from a little less than 1500 Ma ago. Compare PROKARYOTE.
|
|
|
Cite this article
AILSA ALLABY and MICHAEL ALLABY. "eukaryote." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "eukaryote." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-eukaryote.html AILSA ALLABY and MICHAEL ALLABY. "eukaryote." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-eukaryote.html |
|
eukaryote
eukaryote An organism whose cells have a distinct nucleus (i.e. all protists, fungi, plants, and animals). The first eukaryotes were almost certainly green algae (Chlorophyceae) and what appear to be their microscopic remains occur in Precambrian sediments dating from a little less than 1500 Ma ago.
|
|
|
Cite this article
MICHAEL ALLABY. "eukaryote." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "eukaryote." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O7-eukaryote.html MICHAEL ALLABY. "eukaryote." A Dictionary of Plant Sciences. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-eukaryote.html |
|
eukaryote
eukaryote (eucaryote) An organism consisting of cells in which the genetic material is contained within a distinct nucleus. All organisms except bacteria are eukaryotes. See Eukarya. Compare prokaryote.
|
|
|
Cite this article
"eukaryote." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "eukaryote." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-eukaryote.html "eukaryote." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-eukaryote.html |
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
