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
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.
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.
Bacteria expect the unexpected: Scientists observe the emergence of a new adaptation strategy
Nov 04, 2009 |
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Organisms ensure the survival of their species by genetically adapting to the environment. If environmental conditions change too rapidly, the extinction of a species may be the consequence. A strategy to ...
GSU professor develops new method to help keep fruit, vegetables and flowers fresh
Oct 20, 2009 |
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Did you know that millions of tons of fruits and vegetables in the United States end up in the trash can before being eaten, according to the U.S. Department of Agriculture? A Georgia State University professor has developed ...
How does a worm build a throat? Tackling the 'organ formation puzzle'
Oct 06, 2009 |
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(PhysOrg.com) -- Mention worms to most people, and they probably think of fishing, gardening, or trips to the vet. Mention them to Susan E. Mango, and she begins telling you how “absolutely beautiful” they ...
How mitochondrial gene defects impair respiration, other major life functions
Sep 24, 2009 |
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Researchers are delving into abnormal gene function in mitochondria, structures within cells that power our lives. Mitochondria are the place where energy is generated from the most basic molecules of food. Because this function ...
Photoswitches shed light on spontaneous free swimming in zebrafish (w/ Video)
Sep 16, 2009 |
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A new way to select and switch on one cell type in an organism using light has helped answer a long-standing question about the function of one class of enigmatic nerve cells in the spinal cord.
Ocean acidification: impact on key organisms of oceanic fauna
Sep 15, 2009 |
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In addition to global warming, carbon dioxide emissions cause another, less well-known but equally serious and worrying phenomenon: ocean acidification. Researchers in the Laboratoire d'Océanographie ...
Digging deeper below Antarctica's Lake Vida
Space & Earth / Earth Sciences
Sep 14, 2009 |
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(PhysOrg.com) -- Antarctica's Lake Vida, a geologic curiosity that is essentially an ice bottle of brine, is home to some of the oldest and coldest living organisms on Earth. Perpetually covered by more than 60 feet of ice, ...
Study Reveals Unexpected Ancient Cellular Structure
Sep 10, 2009 |
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(PhysOrg.com) -- Scientists at North Carolina State University have effectively lifted the veil from the structure of an ancient and important RNA-protein complex essential for the biosynthesis and function of the ribosome, ...
First discovery of life's building block in comet made
Space & Earth / Space Exploration
Aug 17, 2009 |
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(PhysOrg.com) -- NASA scientists have discovered glycine, a fundamental building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft.
Some mice stem cells divide in unexpected ways
Aug 14, 2009 |
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(PhysOrg.com) -- Using new genetic tools, Cornell researchers have found that some stem cells in mice behave dramatically different than in fruit flies, where most of the pioneering stem cell work has been ...
Parasites ready to jump: How the cell represses mobile genetic elements
Jul 31, 2009 |
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Transposons are mobile genetic elements found in the hereditary material of humans and other organisms. They can replicate and the new copies can insert at novel sites in the genome. Because this threatens the whole organism, ...
Scientists discover Amazon river is 11 million years old
Space & Earth / Earth Sciences
Jul 29, 2009 |
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Researchers at the University of Liverpool have discovered that the Amazon river, and its transcontinental drainage, is around 11 million years old and took its present shape about 2.4 million years ago.
Earliest animals lived in a lake environment, research shows
Other Sciences / Archaeology & Fossils
Jul 27, 2009 |
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Evidence for life on Earth stretches back billions of years, with simple single-celled organisms like bacteria dominating the record. When multi-celled animal life appeared on the planet after 3 billion years ...
