The bacteria ( [bækˈtɪərɪə] (help·info); singular: bacterium)[α] are a large group of unicellular, prokaryote The prokaryotes are a group of organisms that lack a cell nucleus (= karyon), or any other membrane-bound organelles. They differ from the eukaryotes, which have a cell nucleus. Most are unicellular, but a few prokaryotes such as myxobacteria have multicellular stages in their life cycles. The word prokaryote comes from the Greek πρό- (pro-) &, microorganisms A microorganism or microbe is an organism that is microscopic (usually too small to be seen by the naked human eye). 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. Typically a few micrometres A micrometre or micron is one millionth of a metre, or equivalently one thousandth of a millimetre or one thousand nanometres. It can also be written in scientific notation as 1×10−6 m, meaning 1⁄1000000 m in length, bacteria have a wide range of shapes, ranging from spheres A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in three dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point. This distance r is known as the radius of the sphere. The to rods and spirals. Bacteria are ubiquitous in every habitat A habitat is an ecological or environmental area that is inhabited by a particular species of animal or plantor rock with a face (because they are living when they have a face) or other type of organism. It is the natural environment in which an organism lives, or the physical environment that surrounds (influences and is utilized by) a species on Earth Earth is the third planet from the Sun, and the fifth-largest of the eight planets in the Solar System. It is also the largest, most massive, and densest of the Solar System's four terrestrial planets. It is sometimes referred to as the World, the Blue Planet,[note 3] or Terra.[note 4], growing in soil, acidic hot springs A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are hot springs all over the earth, on every continent and even under the oceans and seas, radioactive waste Radioactive waste is a waste product containing radioactive material. It is usually the product of a nuclear process such as nuclear fission. However, industries not directly connected to the nuclear industry may produce quantities of radioactive waste. The majority of radioactive waste is "low-level waste", meaning it contains low,[2] water, and deep in the Earth's crust In geology, a crust is the outermost solid shell of a rocky planet or moon, which is chemically distinct from the underlying mantle. The crusts of Earth, our Moon, Mercury, Venus, Mars, Io, and other planetary bodies have been generated largely by igneous processes, and these crusts are richer in incompatible elements than their respective mantles, as well as in organic matter and the live bodies of plants and animals. There are typically 40 million bacterial cells The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. Some organisms, such as most bacteria, are unicellular . Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion in a gram of soil and a million bacterial cells in a millilitre of fresh water Freshwater or fresh water is naturally occurring water on the Earth's surface in bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Freshwater is characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and; in all, there are approximately five nonillion The following table lists those names of large numbers which are found in many English dictionaries and thus have a special claim to being "real words". The "Traditional British" values shown are unused in American English and are obsolete[citation needed] in British English, but are dominant in many non-English-speaking areas, (5×1030) bacteria on Earth,[3] forming much of the world's biomass How biomass is measured depends on why it is being measured. Sometimes the biomass is regarded as the natural mass of organisms in situ, just as they are. For example, in a salmon fishery, the salmon biomass might be regarded as the total wet weight the salmon would have if they were taken out of the water. In other contexts, biomass can be.[3] Bacteria are vital in recycling nutrients, with many steps in nutrient cycles In ecology and Earth science, a biogeochemical cycle or nutrient cycle is a pathway by which a chemical element or molecule moves through both biotic and abiotic (lithosphere, atmosphere, and hydrosphere) compartments of Earth. In effect, the element is recycled, although in some cycles there may be places (called reservoirs) where the element is depending on these organisms, such as the fixation of nitrogen Nitrogen fixation usually refers to the biological process by which nitrogen in the atmosphere is converted into ammonia. This process is essential for life because fixed nitrogen is required to biosynthesize the basic building blocks of life, e.g. nucleotides for DNA and amino acids for proteins. Formally, nitrogen fixation also refers to other from the atmosphere The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night. Dry air contains roughly (by volume) 78% nitrogen, 21% and putrefaction Putrefaction is the decomposition of animal proteins, especially by anaerobic microorganisms, described as putrefying bacteria. Decomposition is a more general process. Putrefaction usually results in amines such as putrescine and cadaverine, which have a putrid odor. Material that is subject to putrefaction is called putrescible. However, most bacteria have not been characterized, and only about half of the phyla In biology, a phylum [note 1] is a taxonomic rank below Kingdom and above Class. "Phylum" is equivalent to the botanical term division of bacteria have species that can be grown A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture media under controlled laboratory conditions. Microbial cultures are used to determine the type of organism, its abundance in the sample being tested, or both. It is one of the primary diagnostic in the laboratory.[4] The study of bacteria is known as bacteriology Microbiology is the study of microorganisms, which are unicellular or cell-cluster microscopic organisms. This includes eukaryotes such as fungi and protists, and prokaryotes. Viruses, though not strictly classed as living organisms, are also studied. In short; microbiology refers to the study of life and organisms that are too small to be seen, a branch of microbiology Microbiology is the study of microorganisms, which are unicellular or cell-cluster microscopic organisms. This includes eukaryotes such as fungi and protists, and prokaryotes. Viruses, though not strictly classed as living organisms, are also studied. In short; microbiology refers to the study of life and organisms that are too small to be seen.
There are approximately ten times as many bacterial cells in the human flora The human flora is the assemblage of microorganisms that reside on the surface and in deep layers of skin, in the saliva and oral mucosa, and in the gastrointestinal tracts. They include bacteria, fungi and archaea. Some of these organisms are known to perform tasks that are useful for the human host, while the majority have no known beneficial or of bacteria as there are human cells in the body, with large numbers of bacteria on the skin The skin is a soft outer covering of an animal, in particular a vertebrate. Other animal coverings such the arthropod exoskeleton or the seashell have different developmental origin, structure and chemical composition. The adjective cutaneous literally means "of the skin" . In mammals, the skin is the largest organ of the integumentary and as gut flora Gut flora consists of microorganisms that live in the digestive tracts of animals, and is the largest reservoir of human flora. "Gut" is synonymous with intestinal and "flora" with microbiota and microflora.[5] The vast majority of the bacteria in the body are rendered harmless by the protective effects of the immune system An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumour cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own healthy cells and tissues in order to function, and a few are beneficial Probiotics are live microorganisms thought to be healthy for the host organism. According to the currently adopted definition by FAO/WHO, probiotics are: "Live microorganisms which when administered in adequate amounts confer a health benefit on the host". Lactic acid bacteria and bifidobacteria are the most common types of microbes used. However, a few species of bacteria are pathogenic Pathogenic bacteria are bacteria that cause infectious diseases. This article deals with human pathogenic bacteria and cause infectious diseases An infectious disease is a clinically evident illness resulting from the presence of pathogenic microbial agents, including pathogenic viruses, pathogenic bacteria, fungi, protozoa, multicellular parasites, and aberrant proteins known as prions. These pathogens are able to cause disease in animals and/or plants. Infectious pathologies are also, including cholera Cholera, sometimes known as Asiatic or epidemic cholera, is an infectious gastroenteritis caused by enterotoxin-producing strains of the bacterium Vibrio cholerae. Transmission to humans occurs through eating food or drinking water contaminated with Vibrio cholerae from other cholera patients. The major reservoir for cholera was long assumed to be, syphilis Syphilis is a sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum subspecies pallidum. The route of transmission of syphilis is almost always through sexual contact, although there are examples of congenital syphilis via transmission from mother to child in utero, anthrax Anthrax is an acute disease caused by Bacillus anthracis. It affects both humans and other animals. Most forms of the disease are lethal. There are effective vaccines against anthrax, and some forms of the disease respond well to antibiotic treatment, leprosy Leprosy or Hansen's disease , named after physician Gerhard Armauer Hansen, is a chronic disease caused by the bacteria Mycobacterium leprae and Mycobacterium lepromatosis. Leprosy is primarily a granulomatous disease of the peripheral nerves and mucosa of the upper respiratory tract; skin lesions are the primary external sign. Left untreated, and bubonic plague Bubonic plague is the best known manifestation of the bacterial disease plague, caused by the Gram-negative bacterium Yersinia pestis . It belongs to the family Enterobacteriaceae. The term "bubonic plague" was often used synonymously for plague, but it does in fact refer specifically to an infection that enters through the skin and. The most common fatal bacterial diseases are respiratory infections, with tuberculosis Tuberculosis or TB is a common and often deadly infectious disease caused by mycobacteria, usually Mycobacterium tuberculosis in humans. Tuberculosis usually attacks the lungs but can also affect other parts of the body. It is spread through the air, when people who have the disease cough, sneeze, or spit. Most infections in humans result in an alone killing about 2 million people a year, mostly in sub-Saharan Africa Sub-Saharan Africa is a geographical term used to describe the area of the African continent which lies south of the Sahara, or those African countries which are fully or partially located south of the Sahara. It contrasts with North Africa, which is considered a part of the Arab world.[6] In developed countries The term developed country is used to describe countries that have a high level of development according to some criteria. Which criteria, and which countries are classified as being developed, is a contentious issue and is surrounded by fierce debate. Economic criteria have tended to dominate discussions. One such criterion is income per capita;, antibiotics In common usage, an antibiotic is a substance or compound that kills, or inhibits the growth of, bacteria. Antibiotics belong to the broader group of antimicrobial compounds, used to treat infections caused by microorganisms, including fungi and protozoa.[citation needed] are used to treat bacterial infections An infection is the detrimental colonization of a host organism by a foreign species. In an infection, the infecting organism seeks to utilize the host's resources to multiply, usually at the expense of the host. The infecting organism, or pathogen, interferes with the normal functioning of the host and can lead to chronic wounds, gangrene, loss and in agriculture, so antibiotic resistance Antibiotic resistance is a specific type of drug resistance when a microorganism has the ability of withstanding the effects of antibiotics. Antibiotic resistance evolves via natural selection acting upon random mutation, but it can also be engineered by applying an evolutionary stress on a population. Once such a gene is generated, bacteria can is becoming common. In industry, bacteria are important in sewage treatment Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater and household sewage, both runoff and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants. Its objective is to produce a waste stream (or treated effluent) and a solid, the production of cheese Cheese consists of proteins and fat from milk, usually the milk of cows, buffalo, goats, or sheep. It is produced by coagulation of the milk protein casein. Typically, the milk is acidified and addition of the enzyme rennet causes coagulation. The solids are separated and pressed into final form. Some cheeses have molds on the rind or throughout and yoghurt Yoghurt or yogurt is a dairy product produced by bacterial fermentation of milk. Fermentation of lactose produces lactic acid, which acts on milk protein to give yoghurt its texture and its characteristic tang. Soy yoghurt, a non-dairy yoghurt alternative, is made from soy milk. Dairy yoghurt is produced using a culture of Lactobacillus through fermentation Fermentation is the process of deriving energy from the oxidation of organic compounds, such as carbohydrates, and using an endogenous electron acceptor, which is usually an organic compound, as opposed to Respiration where electrons are donated to an exogenous electron acceptor, such as oxygen, via an electron transport chain. Fermentation does, as well as in biotechnology Biotechnology is technology based on biology, agriculture, food science, and medicine. Modern use of the term refers to genetic engineering as well as cell- and tissue culture technologies. However, the concept encompasses a wider range and history of procedures for modifying living organisms according to human purposes, going back to, and the manufacture of antibiotics and other chemicals.[7]
Once regarded as plants constituting the class Schizomycetes, bacteria are now classified as prokaryotes The prokaryotes are a group of organisms that lack a cell nucleus (= karyon), or any other membrane-bound organelles. They differ from the eukaryotes, which have a cell nucleus. Most are unicellular, but a few prokaryotes such as myxobacteria have multicellular stages in their life cycles. The word prokaryote comes from the Greek πρό- (pro-) &. Unlike cells of animals and other eukaryotes A eukaryote is an organism whose cells contain complex structures inside the membranes. The defining membrane-bound structure that sets eukaryotic cells apart from prokaryotic cells is the nucleus, or nuclear envelope, within which the genetic material is carried. The presence of a nucleus gives eukaryotes their name, which comes from the Greek ε, bacterial cells do not contain a nucleus In cell biology, the nucleus , also sometimes referred to as the "control center", is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes and rarely harbour membrane-bound The cell membrane is one biological membrane separating the interior of a cell from the outside environment organelles In cell biology, an organelle is a specialized subunit within a cell that has a specific function, and is usually separately enclosed within its own lipid bilayer. Although the term bacteria traditionally included all prokaryotes, the scientific classification Biological classification, or scientific classification in biology, is a method by which biologists group and categorize organisms by biological type, such as genus or species. Biological classification is a form of scientific taxonomy, but should be distinguished from folk taxonomy, which lacks scientific basis. Modern biological classification changed after the discovery in the 1990s that prokaryotes consist of two very different groups of organisms that evolved independently from an ancient common ancestor. These evolutionary domains are called Bacteria and Archaea.[8]
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PRLog.Org (press release)
... in which Georgia-Pacific Professional is a member, revealed that paper towels can reduce up to 77 percent of bacteria present on hands after washing2. ...
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Stuart Fox
Wed, 20 Jan 2010 18:00:34 GM
The UCSD researchers have created a mechanism for cyclical gene expression in . bacteria. that can then be propagated throughout an entire bacterial colony like a wave. In the video above, the . bacteria. are reading the gene for a ...
Q. Or any that might grow in his/her living environment. What are the negatives of letting a hamster/mouse/gerbil cage get rather dirty and other than bugs what bacteria or illness could this attract other than wet tail? And what bacteria causes wet-tail?
Asked by Shhhh - Wed Jan 2 20:36:42 2008 - - 3 Answers - 0 Comments
A. For rats and mice (and cats, snakes, birds, cows...), mycobacteria is common. It causes respiratory problems ranging from mild to deadly. For rabbits, guinea pigs, hamsters and gerbils, Tyzzer's disease is more of a concern. (as well as it is a concern for cows, horses, monkeys, and other animals) Its caused by the bacteria Clostridium piliforne. It is deadly, highly contagious, and most often mistaken for "wet tail". Besides tyzzer's and myco, not cleaning the cage can lead to ammonia poisoning, stroke, seizures, liver failure, kidney failure, and many other problems associated with a buildup of ammonia. Even if you only let the cages get nasty once or twice, the little bit of internal damage is permanent, and the lifespan is shortened… [cont.]
Answered by bzzflygirl - Wed Jan 2 23:41:54 2008
