single+cell+organism

hi here are some notes on single cell organism =Microorganism= From Wikipedia, the free encyclopedia (Redirected from [|Single cell organism]) "Microbe" redirects here. For other uses, see [|Microbe (disambiguation)]. A cluster of //[|Escherichia coli]// [|Bacteria] magnified 10,000 times. A **micro-organism** (from the [|Greek]: μικρός, //mikrós//, "small" and ὀργανισμός, //organismós//, "organism"; also spelt **micro-organism**, **micro organism** or **microörganism**) or **microbe** is a [|microscopic] [|organism] that comprises either a single cell ([|unicellular]), cell clusters, or no cell at all ([|acellular]).[|[][|1][|]] The study of microorganisms is called [|microbiology], a subject that began with [|Anton van Leeuwenhoek]'s discovery of microorganisms in 1675, using a [|microscope] of his own design. Microorganisms are very diverse; they include [|bacteria], [|fungi], [|archaea], and [|protists]; microscopic [|plants] ([|green algae]); and [|animals] such as [|plankton] and the [|planarian]. Some microbiologists also include [|viruses], but others consider these as non-living.[|[][|2][|]][|[][|3][|]] Most microorganisms are [|unicellular] (single-celled), but this is not universal, since some [|multicellular] organisms are [|microscopic], while some unicellular protists and bacteria, like //[|Thiomargarita namibiensis]//, are [|macroscopic] and visible to the naked eye.[|[][|4][|]] Microorganisms live in all parts of the [|biosphere] where there is liquid [|water], including [|soil], [|hot springs], on the [|ocean] floor, high in the [|atmosphere] and deep inside rocks within the Earth's [|crust]. Microorganisms are critical to nutrient recycling in [|ecosystems] as they act as [|decomposers]. As some microorganisms can [|fix nitrogen], they are a vital part of the [|nitrogen cycle], and recent studies indicate that airborne microbes may play a role in [|precipitation] and weather.[|[][|5][|]] Microbes are also exploited by people in [|biotechnology], both in traditional [|food and beverage preparation], and in modern technologies based on [|genetic engineering]. However, [|pathogenic microbes] are harmful, since they invade and grow within other organisms, causing [|diseases] that kill humans, other animals and plants.[|[][|6][|]]