Bacteria (/bækˈtɪəriə/ ( listen); singular: bacterium) are a large domain of prokaryotic microorganisms.
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Bacteria (/bækˈtɪəriə/ ( listen); singular: bacterium) are a large domain of prokaryotic microorganisms.<br>
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Bacteria are found everywhwere. - even on you ! <br>Approximately 2,000 species have been identified, many of them living in conditions that would destroy other organisms.<br> They have been found in the almost airless reaches of the upper atmosphere, <br>10 km (6 mi) below the surface of the ocean, in frozen soil, and on rocks in hot springs.<br> Some bacteria produce a resting stage, the endospore, which is the most resistant living thing <br>known and can be killed only by boiling in steam under pressure for many hours.<br>
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'''Size of bacteria:'''
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Thirty trillion bacteria of average size weigh about 28 g (1 oz). Bacteria are measured in microns (0.001 micrometer, about 0.00004 in) and most types range from 0.1 to 4.0 microns in width and 0.2 to 50 microns in length.