Crossword clues for bacteria
Longman Dictionary of Contemporary English
The Collaborative International Dictionary
Bacteria \Bac*te"ri*a\, n. pl. See Bacterium.
Bacterium \Bac*te"ri*um\ (b[a^]k*t[=e]"r[i^]*[u^]m), n.; pl. Bacteria (b[a^]k*t[=e]"r[i^]*[.a]). [NL., fr. Gr. bakth`rion, ba`ktron, a staff: cf. F. bact['e]rie.] (Biol.) A microscopic single-celled organism having no distinguishable nucleus, belonging to the kingdom Monera. Bacteria have varying shapes, usually taking the form of a jointed rodlike filament, or a small sphere, but also in certain cases having a branched form. Bacteria are destitute of chlorophyll, but in those members of the phylum Cyanophyta (the blue-green algae) other light-absorbing pigments are present. They are the smallest of microscopic organisms which have their own metabolic processes carried on within cell membranes, viruses being smaller but not capable of living freely. The bacteria are very widely diffused in nature, and multiply with marvelous rapidity, both by fission and by spores. Bacteria may require oxygen for their energy-producing metabolism, and these are called aerobes; or may multiply in the absence of oxygen, these forms being anaerobes. Certain species are active agents in fermentation, while others appear to be the cause of certain infectious diseases. The branch of science with studies bacteria is bacteriology, being a division of microbiology. See Bacillus.
Douglas Harper's Etymology Dictionary
1847, plural of Modern Latin bacterium, from Greek bakterion "small staff," diminutive of baktron "stick, rod," from PIE *bak- "staff used for support" (also source of Latin baculum "rod, walking stick"). So called because the first ones observed were rod-shaped. Introduced as a scientific word 1838 by German naturalist Christian Gottfried Ehrenberg (1795-1876).
Etymology 1 n. 1 (plural of bacterium English)Category:English plurals 2 (context US English) A type, species, or strain of bacterium Etymology 2
n. (context dated medicine English) An oval bacterium, as distinguished from a spherical coccus or rod-shaped bacillus
n. (microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered plants [syn: bacterium]
The bacteria are a major group of prokaryotic living organisms.
Bacteria may also refer to:
- Bacteria (malware) or Rabbit Programs, a type of malicious software
- Bacteria, a fictional country in The Great Dictator
- Bacteria, the wife of Unhygienix in the Asterix comics
- Bacteriidae, a family of South American stick insects
Bacteria (; singular: bacterium) constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep portions of Earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals.
There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water. There are approximately 5×10 bacteria on Earth, forming a biomass which exceeds that of all plants and animals. Bacteria are vital in recycling nutrients, with many of the stages in nutrient cycles dependent on these organisms, such as the fixation of nitrogen from the atmosphere and putrefaction. In the biological communities surrounding hydrothermal vents and cold seeps, bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. On 17 March 2013, researchers reported data that suggested bacterial life forms thrive in the Mariana Trench, which with a depth of up to 11 kilometres is the deepest part of the Earth's oceans. Other researchers reported related studies that microbes thrive inside rocks up to 580 metres below the sea floor under 2.6 kilometres of ocean off the coast of the northwestern United States. According to one of the researchers, "You can find microbes everywhere — they're extremely adaptable to conditions, and survive wherever they are."
Most bacteria have not been characterized, and only about half of the bacterial phyla have species that can be grown in the laboratory. The study of bacteria is known as bacteriology, a branch of microbiology.
There are approximately ten times as many bacterial cells in the human flora as there are human cells in the body, with the largest number of the human flora being in the gut flora, and a large number on the skin. The vast majority of the bacteria in the body are rendered harmless by the protective effects of the immune system, and some are beneficial. However, several species of bacteria are pathogenic and cause infectious diseases, including cholera, syphilis, anthrax, leprosy, and bubonic plague. The most common fatal bacterial diseases are respiratory infections, with tuberculosis alone killing about 2 million people per year, mostly in sub-Saharan Africa. In developed countries, antibiotics are used to treat bacterial infections and are also used in farming, making antibiotic resistance a growing problem. In industry, bacteria are important in sewage treatment and the breakdown of oil spills, the production of cheese and yogurt through fermentation, and the recovery of gold, palladium, copper and other metals in the mining sector, as well as in biotechnology, and the manufacture of antibiotics and other chemicals.
Once regarded as plants constituting the class Schizomycetes, bacteria are now classified as prokaryotes. Unlike cells of animals and other eukaryotes, bacterial cells do not contain a nucleus and rarely harbour membrane-bound organelles. Although the term bacteria traditionally included all prokaryotes, the scientific classification changed after the discovery in the 1990s that prokaryotes consist of two very different groups of organisms that evolved from an ancient common ancestor. These evolutionary domains are called Bacteria and Archaea.
Usage examples of "bacteria".
In appearance they are not very different from conventional bacteria, but at high magnification, or rather, at a relatively high magnification, the highest magnification a conventional school microscope is capable of, if you look very carefully you could see some particles inside that have regular geometric shapes.
Some of the bacteria were marked with a felt pen circles, and inside those one could indeed see some rectangles and geometrically perfect spheres that were interconnected by some strings and pipes.
Although individual bacteria also use omnidirectional radiation to communicate with their closest neighbors at the distances of up to a few millimeters, the strength of such signal is very low and it cannot be used for communications at a long range of, say, tens of meters.
For long-range communications, groups of neighboring bacteria cooperate with each other to create, for the time of a long-range communications session, a sort of phased antenna array with a pencil-beam radiation pattern.
Those would pass on their message to other bacteria living further down along the water-pipe, those other ones would pass the message to still other ones, and so on, all the way to the Atlantic Ocean.
And the ocean is teeming with these bacteria, so from there on the message would be traveling very fast.
And their memories do hold something, and it seems that a considerable portion of those memories differ from one bacteria to another.
The bacteria that have tapped into your nerve fiber in the same way as an eavesdropping device might tap into a phone line, intercept these pulses, convert them into infrared radiation that is transmitted to another group of bacteria located a few dozen feet from you, those other bacteria pass it on to yet another group, and so on.
Since these bacteria already live inside everyone on Earth anyway, we could safely assume that they also live inside those who might be eavesdropping on us in Moscow.
We could also assume that one of the cyborg-bacteria has hooked up to his auditory nerve in the same way as it did to yours, the only difference being that your bacteria is recording electrical pulses coming from your ear, while his bacteria is reproducing these pulses, inducing them in his auditory nerve.
Some of them even go as far as to say that that the only thing needed for the further work on the bacteria hybrid was the bacteria itself, since it already had in itself all the tools required for any further modifications or upgrades, and that means that all the further development effort could be conducted at home.
Inside me, just as inside you and all the other people on Earth, there now live the same cyborg-bacteria, and these particular bacteria inside your body provide an interface between the nervous system of your body and the NanoTech System, that is, all the other cyborg-bacteria that live throughout the globe.
Physical interface is implemented by the bacteria attached to the nerve fibers in your body, who tap into the action currents in these fibers and convert them into infrared signals used for data exchange between cyborg-bacteria.
Physically, the copying process went as follows: the object to be copied was submerged into a tank with water containing cyborg-bacteria, and these bacteria gradually disassembled, one might even say dissolved, the object atom by atom.
The surface color and reflectivity can also be varied by arranging the bacteria into different configurations, so that light waves of one wavelength cancel each other, while the waves of another length reinforce each other, giving the object a certain color, making it light or dark.