Related topics: cells · protein · bacteria · genes · mutations

Super volcanic eruptions interrupt ozone recovery

Since the Antarctic ozone hole was detected in 1985, depletion of the ozone layer—the "big umbrella" that protects all life on Earth—has raised considerable concern. The efforts of international communities led to the ...

The habitability of Titan and its ocean

Saturn's largest moon, Titan, is a hotbed of organic molecules, harboring a soup of complex hydrocarbons similar to that thought to have existed over four billion years ago on the primordial Earth. Titan's surface, however, ...

How multicellular cyanobacteria transport molecules

Researchers from ETH Zurich and the University of Tübingen have taken a high-resolution look at the structure and function of cell-to-cell connections in filamentous, multicellular cyanobacteria. This enables them to explain ...

Nanotechnology delivers hepatitis B vaccine

Brazilian and European researchers have demonstrated exactly how a nanotechnology-based compound delivers an oral vaccine against hepatitis B to the immune system. When particles containing silica and an antigen combine, ...

Organic porous structures on 2-D defect networks

NUS scientists have developed a method for self-assembly of hexagonal organic porous structures on molybdenum diselenide (MoSe2) film to create ordered nanostructures.

On the way to printable organic light emitting diodes

Organic light-emitting diodes are components that no longer consist of compounds containing the semiconducting material gallium, but of so-called organic compounds in which carbon is a main component. Compared to conventional ...

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Organism

In 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.

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