Organism
hideIn biology, an organism is any living system (such as animal, plant, fungus, or micro-organism). In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homeostasis as a stable whole. An organism may either be unicellular (single-celled) or be composed of, as in humans, many billions of cells grouped into specialized tissues and organs. The term multicellular (many-celled) describes any organism made up of more than one cell.
The terms "organism" (Greek ὀργανισμός - organismos, from Ancient Greek ὄργανον - organon "organ, instrument, tool") first appeared in the English language in 1701 and took on its current definition by 1834 (Oxford English Dictionary).
Scientific classification in biology considers organisms synonymous with life on Earth. Based on cell type, organisms may be divided into the prokaryotic and eukaryotic groups. The prokaryotes represent two separate domains, the Bacteria and Archaea. Eukaryotic organisms, with a membrane-bounded cell nucleus, also contain organelles, namely mitochondria and (in plants) plastids, generally considered to be derived from endosymbiotic bacteria. Fungi, animals and plants are examples of species that are eukaryotes.
More recently a clade, Neomura, has been proposed, which groups together the Archaea and Eukarya. Neomura is thought to have evolved from Bacteria, more specifically from Actinobacteria.
For more information about Organism, read the full article at
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News tagged with organisms
Peptides control crystal growth with 'switches, throttles and brakes'
Nanotechnology / Bio & Medicine
Nov 23, 2009 |
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(PhysOrg.com) -- By producing some of the highest resolution images of peptides attaching to mineral surfaces, scientists have a deeper understanding how biomolecules manipulate the growth crystals. This research ...
What is the meaning of 'one'? Evolutionary biologists argue for new meaning of 'organismality'
Nov 09, 2009 |
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Rice University evolutionary biologists David Queller and Joan Strassmann argue in a new paper that high cooperation and low conflict between components, from the genetic level on up, give a living thing its "organismality," ...
Scientists Reproduce a Building Block of Life in Laboratory
Nov 06, 2009 |
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(PhysOrg.com) -- NASA scientists studying the origin of life have reproduced uracil, a key component of our hereditary material, in the laboratory.
Acid test: Study reveals both losers and winners of CO2-induced ocean acidification
Space & Earth / Earth Sciences
Dec 01, 2009 |
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(PhysOrg.com) -- As the world’s seawater becomes more acidic due to rising atmospheric carbon dioxide, some shelled marine creatures may actually become bigger and stronger, according to a new study.
UK starts study on using human DNA in animals
Nov 09, 2009 |
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(AP) -- British scientists begin a new study on Tuesday to consider how human DNA is used in animal experiments and to determine what the boundaries of such controversial science might be.
New insights into the physiology of cockroaches
Nov 13, 2009 |
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A study by scientists from the University of Valencia sheds new light on how the cockroach organism works. A research team from the Cavanilles Institute for Biodiversity and Evolutionary Biology, led by professors Amparo ...
Caribbean, Gulf spared widespread coral damage
Nov 06, 2009 |
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(AP) -- Lower-than-feared sea temperatures this summer gave a break to fragile coral reefs across the Caribbean and the central Gulf of Mexico that were damaged in recent years, scientists said Thursday.
