A cluster of Escherichia coli bacteria magnified 10,000 times. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have

A microorganism (also can be spelled as micro organism) or microbe is an organism that is microscopic (too small to be seen by the naked human eye). Microscopic is a term used to describe objects smaller than those that can easily be seen by the naked Eye and which require a lens or Microscope to see 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. Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία Antonie Philips van Leeuwenhoek (October 24 1632 &ndash August 30 1723 was a Dutch tradesman and Scientist from Delft, the Netherlands A microscope ( Greek: ( micron) = small + ( skopein) = to look or see is an instrument for viewing objects that are

Microorganisms are incredibly diverse and include bacteria, fungi, archaea, and protists, as well as some microscopic plants and animals such as plankton, and popularly-known animals such as the planarian and the amoeba. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this Plants are living Organisms belonging to the kingdom Plantae. Micro-animals are Animals that are microscopic and thus cannot be seen with the naked eye Plankton consist of any drifting Organisms ( Animals Plants Archaea, or Bacteria) that inhabit the Pelagic zone of Planaria are nonparasitic Flatworms (which make great pets of the biological family Planariidae, belonging to the order Seriata. Amoeba (sometimes amœba or ameba, plural amoebae) is a Genus of Protozoa that moves They do not include viruses and prions, which are generally classified as non-living. A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable A prion (ˈpriːɒn is thought to be an infectious agent that according to current scientific consensus is comprised entirely of a propagated, mis-folded Most microorganisms are single-celled, or unicellular, but some multicellular organisms are microscopic, while some unicellular protists, and a bacteria called Thiomargarita namibiensis are visible to the naked eye. The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called Thiomargarita namibiensis ("Sulfur pearl of Namibia " is a Gram-negative Coccus Proteobacterium found in the ocean sediments

Microorganisms live in all parts of the biosphere where there is liquid water, including hot springs, on the ocean floor, high in the atmosphere and deep inside rocks within the Earth's crust. The biosphere is the broadest level of ecological study the global sum of all Ecosystems. Water is a common Chemical substance that is essential for the survival of all known forms of Life. A hot spring is a spring that is produced by the emergence of geothermally heated Groundwater from the earth's crust. An ocean (from Greek, ''Okeanos'' (Oceanus) is a major body of saline water, and a principal component of the Hydrosphere. An atmosphere (from Greek ατμός - atmos, " Vapor " + σφαίρα - sphaira, " Sphere " Microorganisms are critical to nutrient recycling in ecosystems as they act as decomposers. An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical ( Decomposers (or Saprotrophs) are organisms that consume dead organisms and in doing so carry out the natural process of Decomposition. 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. Nitrogen fixation is the process by which Nitrogen is taken from its natural relatively inert molecular form (N2 in the atmosphere and converted into The nitrogen cycle is the Biogeochemical cycle that describes the transformations of Nitrogen and nitrogen-containing compounds in nature In Meteorology, precipitation (also known as one class of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric The weather is a set of all the phenomena occurring in a given Atmosphere at a given Time. ^[1]

Microbes are also exploited by people in biotechnology, both in traditional food and beverage preparation, as well as modern technologies based on genetic engineering. Biotechnology is Technology based on Biology, especially when used in Agriculture, Food science, and Medicine. Fermentation in Food processing typically refers to the conversion of Sugar to Alcohol using Yeast under Anaerobic conditions Genetic engineering, Recombinant DNA technology, genetic modification/manipulation (GM and gene splicing are terms that apply to the direct However, pathogenic microbes are harmful, since they invade and grow within other organisms, causing diseases that kill millions of people, other animals, and plants. A pathogen (from Greek πάθος pathos "suffering passion" and γἰγνομαι (γεν- gignomai (gen- "I give birth to" infectious A disease is an abnormal condition of an organism that impairs bodily functions and can be deadly ^[2]

History

Evolution

Further information: Timeline of evolution

Single-celled microorganisms were the first forms of life to develop on earth, approximately 3–4 billion years ago. This timeline of the evolution of life outlines the major events in the development In the Natural sciences, Abiogenesis, or origin of life, is the study of how Life on Earth emerged from Inanimate Organic To help compare Orders of magnitude of different times this page lists times between 1017 seconds and 1018 seconds (3 ^[3][4][5] Further evolution was slow,^[6] and for about 3 billion years in the Precambrian eon, all organisms were microscopic. The Precambrian ( Pre-Cambrian) is an informal name for the supereon comprising the eons of the Geologic timescale that came before the current ^[7] So, for most of the history of life on Earth the only form of life were microorganisms. ^[8] Bacteria, algae and fungi have been identified in amber that is 220 million years old, which shows that the morphology of microorganisms has changed little since the triassic period. Amber is Fossil tree Resin, which is appreciated for its color and beauty The Triassic is a geologic period and system that extends from about 251 to 199 Ma (million years ago ^[9]

Most microorganisms can reproduce rapidly and microbes such as bacteria can also freely exchange genes by conjugation, transformation and transduction between widely-divergent species. Bacterial conjugation is the transfer of genetic material between bacteria through direct cell-to-cell contact In Molecular biology, transformation is the genetic alteration of a cell resulting from the uptake genomic incorporation and expression of foreign Transduction is the process by which DNA is transferred from one Bacterium to another by a Virus. ^[10] This horizontal gene transfer, coupled with a high mutation rate and many other means of genetic variation, allows microorganisms to swiftly evolve (via natural selection) to survive in new environments and respond to environmental stresses. In biology mutations are changes to the Nucleotide sequence of the Genetic material of an organism The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have eVolution is the third Album by eLDee, it was due to be released in 2008 Natural selection is the process by which favorable Heritable traits become more common in successive Generations of a Population of This rapid evolution is important in medicine, as it has led to the recent development of 'super-bugs' — pathogenic bacteria that are resistant to modern antibiotics. Antibiotic resistance is the ability of a Microorganism to withstand the effects of Antibiotics. A pathogen (from Greek πάθος pathos "suffering passion" and γἰγνομαι (γεν- gignomai (gen- "I give birth to" infectious The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have In modern usage an antibiotic is a Chemotherapeutic agent with activity against Microorganisms such as Bacteria, fungi or Protozoa ^[11]

Pre-Microbiology

The possibility that microorganisms might exist was discussed for many centuries before their actual discovery in the 17th century. The first ideas about microorganisms were those of the Roman scholar Marcus Terentius Varro in a book titled On Agriculture in which he warns against locating a homestead near swamps:

This passage seems to indicate that the ancients were aware of the possibility that diseases could be spread by yet unseen organisms.

In The Canon of Medicine (1020), Abū Alī ibn Sīnā (Avicenna) stated that bodily secretion is contaminated by foul foreign earthly bodies before being infected. The Canon of Medicine ( Arabic: القانون في الطب Al-Qanun fi al-Tibb " The Law of Medicine " Persian TemplateInfobox Muslim scholars --> ( Persian /ابو علی الحسین ابن عبدالله ابن سینا (born Secretion is the process of segregating elaborating and releasing chemicals from a cell, or a secreted Chemical substance or amount of substance ^[13] He also hypothesized that tuberculosis and other diseases might be contagious, i. Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common e. that they were infectious diseases, and used quarantine to limit their spread. An infectious disease is a clinically evident Disease resulting from the presence of Pathogenic microbial agents including Pathogenic viruses Pathogenic For other uses see Quarantine (disambiguation Quarantine is voluntary or compulsory isolation typically to contain the spread of something ^[14]

When the Black Death bubonic plague reached al-Andalus in the 14th century, Ibn Khatima wrote that infectious diseases were caused by "contagious entities" that enter the human body. The Black Death, or the Black Plague, was one of the deadliest Pandemics in human history widely thought to have been caused by a bacterium named Yersinia Bubonic plague is the best-known manifestation of the bacterial disease plague, caused by the bacterium Yersinia pestis (formerly known as Al-Andalus (الأندلس was the Arabic name given to those parts of the Iberian Peninsula governed by Muslims or Later, in 1546, Girolamo Fracastoro proposed that epidemic diseases were caused by transferable seedlike entities that could transmit infection by direct or indirect contact, or even without contact over long distances. Girolamo Fracastoro ( Fracastorius) (1478‑ August 8, 1553) was an Italian Physician, Scholar (in Mathematics In Epidemiology, an epidemic (from Greek epi- upon + demos people is a classification of a disease that appears as new cases in a A disease is an abnormal condition of an organism that impairs bodily functions and can be deadly

All these early claims about the existence of microorganisms were speculative in nature and not based on any data or science. Microorganisms were neither proven, observed, nor correctly and accurately described until the 17th century. The reason for this was that all these early inquiries lacked the most fundamental tool in order for microbiology and bacteriology to exist as a science, and that was the microscope. Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία A microscope ( Greek: ( micron) = small + ( skopein) = to look or see is an instrument for viewing objects that are

Discovery

Antonie van Leeuwenhoek, the first microbiologist and the first to observe microorganisms using a microscope

Anton van Leeuwenhoek was the first person to observe microorganisms, using a microscope of his own design, thereby making him the first microbiologist. Antonie Philips van Leeuwenhoek (October 24 1632 &ndash August 30 1723 was a Dutch tradesman and Scientist from Delft, the Netherlands A microbiologist is a Scientist who works in the field of Microbiology. A microscope ( Greek: ( micron) = small + ( skopein) = to look or see is an instrument for viewing objects that are Antonie Philips van Leeuwenhoek (October 24 1632 &ndash August 30 1723 was a Dutch tradesman and Scientist from Delft, the Netherlands A microscope ( Greek: ( micron) = small + ( skopein) = to look or see is an instrument for viewing objects that are A microbiologist is a Scientist who works in the field of Microbiology. In doing so Leeuwenhoek would make one of the most important contributions to biology and open up the fields of microbiology and bacteriology. Foundations of modern biology There are five unifying principles Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία Prior to Leeuwenhoek's discovery of microorganisms in 1675, it had been a mystery as to why grapes could be turned into wine, milk into cheese, or why food would spoil. For the Tokyo University supercomputer see Gravity Pipe. GRAPE, or GRA phics P rogramming E nvironment is Wine is an Alcoholic beverage made from the fermentation of Grape juice Milk is an opaque white liquid produced by the Mammary glands of female Mammals (including Monotremes. Cheese is a Food made from Milk, usually the milk of cows, Buffalo, Goats or sheep, by coagulation. Leeuwenhoek did not make the connection between these processes and microorganisms, but using a microscope, he did establish that there were forms of life that were not visible to the naked eye. ^[15][16] Leeuwenhoek's discovery, along with subsequent observations by Lazzaro Spallanzani and Louis Pasteur, ended the long-held belief that life spontaneously appeared from non-living substances during the process of spoilage. Lazzaro Spallanzani ( January 10, 1729 - February 12, 1799) was an Italian Biologist whose research of Biogenesis Louis Pasteur (27 December 1822 – 28 September 1895 a French Chemist and Microbiologist, is best known for remarkable breakthroughs in the causes and In the Natural sciences, Abiogenesis, or origin of life, is the study of how Life on Earth emerged from Inanimate Organic

Lazzarro Spallanzani found that microorganisms could only settle in a broth if the broth was exposed to the air. He also found that boiling the broth would sterilise it and kill the microorganisms. Sterilization (or sterilisation, see spelling differences) refers to any process that effectively kills or eliminates transmissible agents (such as Fungi Louis Pasteur expanded upon Spallanzani's findings by exposing boiled broths to the air, in vessels that contained a filter to prevent all particles from passing through to the growth medium, and also in vessels with no filter at all, with air being admitted via a curved tube that would not allow dust particles to come in contact with the broth. By boiling the broth beforehand, Pasteur ensured that no microorganisms survived within the broths at the beginning of his experiment. Nothing grew in the broths in the course of Pasteur's experiment. This meant that the living organisms that grew in such broths came from outside, as spores on dust, rather than spontaneously generated within the broth. In Biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions Thus, Pasteur dealt the death blow to the theory of spontaneous generation and supported germ theory. The germ theory, also called the pathogenic theory of medicine, is a Theory that proposes that Microorganisms are the cause of many Diseases.

In 1876, Robert Koch established that microbes can cause disease. Heinrich Hermann Robert Koch ( December 11 1843 – May 27 1910) was a German Physician. He did this by finding that the blood of cattle who were infected with anthrax always had large numbers of Bacillus anthracis. Anthrax is an acute Disease in humans and animals caused by the bacterium Bacillus anthracis which is highly lethal in some forms Bacillus anthracis is a Gram-positive, facultatively anaerobic, rod-shaped Bacterium of the genus Bacillus. Koch also found that he could transmit anthrax from one animal to another by taking a small sample of blood from the infected animal and injecting it into a healthy one, causing the healthy animal to become sick. He also found that he could grow the bacteria in a nutrient broth, inject it into a healthy animal, and cause illness. Based upon these experiments, he devised criteria for establishing a causal link between a microbe and a disease in what are now known as Koch's postulates. Koch's postulates are four criteria designed to establish a causal relationship between a causative Microbe and a Disease. ^[17] Though these postulates cannot be applied in all cases, they do retain historical importance in the development of scientific thought and can still be used today. ^[18]

Classification and structure

Evolutionary tree showing the common ancestry of all three domains of life. A phylogenetic tree, also called an evolutionary tree, is a tree showing the Evolutionary relationships among various biological Species or other In biological Taxonomy, a domain (also superregnum, superkingdom, or empire) is the highest Taxonomic rank of Organisms ^[19] Bacteria are colored blue, eukaryotes red, and archaea green. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Relative positions of some phyla are shown around the tree. A phylum ( Plural: phyla) is a Taxonomic rank between Kingdom and above Class.

Microorganisms can be found almost anywhere in the taxonomic organization of life on the planet. Taxonomy is the practice and science of classification The word comes from the Greek, taxis (meaning 'order' 'arrangement' and, nomos Bacteria and archaea are almost always microscopic, while a number of eukaryotes are also microscopic, including most protists, some fungi, as well as some animals and plants. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Micro-animals are Animals that are microscopic and thus cannot be seen with the naked eye Viruses are generally regarded as not living and therefore are not microbes, although the field of microbiology also encompasses the study of viruses. A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable Microbiology (from Greek grc μῑκρος mīkros, "small" grc βίος bios, " Life " and grc -λογία

Prokaryotes

Prokaryotes are organisms that lack a cell nucleus and the other organelles found in eukaryotes. In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed In Cell biology, an organelle (pronunciation /ɔː(rgəˡnɛl/ is a specialized subunit within a cell that has a specific function and is usually separately enclosed Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Prokaryotes are almost always unicellular, although some species such as myxobacteria can aggregate into complex structures as part of their life cycle. The myxobacteria (" slime bacteria " are a group of bacteria that predominantly live in the soil These organisms are divided into two groups, the archaea and the bacteria.

Bacteria

Main article: Bacteria

Staphylococcus aureus bacteria magnified about 10,000x

Bacteria are the most diverse and abundant group of organisms on Earth. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Staphylococcus aureus (ˌstæfɨləˈkɒkəs ˈɔriəs literally "Golden Cluster Seed" and also known as golden staph) is the most common cause of The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Bacteria inhabit practically all environments where some liquid water is available and the temperature is below +140 °C. They are found in sea water, soil, air, animals' gastrointestinal tracts, hot springs and even deep beneath the Earth's crust in rocks. Seawater is Water from a Sea or Ocean. On average seawater in the world's oceans has a Salinity of about 3 Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five A hot spring is a spring that is produced by the emergence of geothermally heated Groundwater from the earth's crust. In Geology, rock is a naturally occurring aggregate of Minerals and/or Mineraloids The Earth's outer solid layer the ‘ Lithosphere ^[20] Practically all surfaces which have not been specially sterilized are covered in bacteria. The number of bacteria in the world is estimated to be around five million trillion trillion, or 5 × 10³⁰. ^[21]

Bacteria are practically all invisible to the naked eye, with a few extremely rare exceptions, such as Thiomargarita namibiensis. Thiomargarita namibiensis ("Sulfur pearl of Namibia " is a Gram-negative Coccus Proteobacterium found in the ocean sediments ^[22] They are unicellular organisms and lack membrane-bound organelles. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually Their genome is usually a single loop of DNA, although they can also harbor small pieces of DNA called plasmids. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known A plasmid is an extra-chromosomal DNA molecule separate from the chromosomal DNA which is capable of replicating independently of the chromosomal DNA These plasmids can be transferred between cells through bacterial conjugation. Bacterial conjugation is the transfer of genetic material between bacteria through direct cell-to-cell contact Bacteria are surrounded by a cell wall, which provides strength and rigidity to their cells. A cell wall is a tough flexible and sometimes fairly rigid layer surrounding a cell, located external to the Cell membrane, which provides the cell with structural They reproduce by binary fission or sometimes by budding, but do not undergo sexual reproduction. Binary fission is the form of Asexual reproduction and Cell division used by Prokaryotic organisms (such as Bacteria or Archea) Budding (also called burgeoning) is the formation of a new Organism by the protrusion of part of another organism The Evolution of sexual reproduction is a major puzzle The first Fossilized evidence of sexually reproducing Organisms is from Eukaryotes of the Stenian Some species form extraordinarily resilient spores, but for bacteria this is a mechanism for survival, not reproduction. An endospore is a dormant, tough and non-reproductive structure produced by a small number of Bacteria from the Firmicute phylum The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Under optimal conditions bacteria can grow extremely rapidly and can double as quickly as every 10 minutes. ^[23]

Archaea

Main article: Archaea

Archaea are also single-celled organisms that lack nuclei. In the past, the differences between bacteria and archaea were not recognised and archaea were classified with bacteria as part of the kingdom Monera. Monera are bacteria and other mostly tiny single-celled organisms whose genetic material is loose in the cell However, in 1990 the microbiologist Carl Woese proposed the three-domain system that divided living things into bacteria, archaea and eukaryotes. Carl Richard Woese (born July 15 1928, Syracuse New York) is an American Microbiologist who attended Deerfield Academy The three-domain system is a Biological classification introduced by Carl Woese in 1990 that divides cellular life forms into Archaea, ^[24] Archaea differ from bacteria in both their genetics and biochemistry. For example, while bacterial cell membranes are made from phosphoglycerides with ester bonds, archaean membranes are made of ether lipids. The cell membrane (also called the plasma membrane, plasmalemma, or "phospholipid bilayer" is a Selectively permeable Lipid bilayer Phospholipids are a class of Lipids and are a major component of all Biological membranes All phospholipids contain a Diglyceride, a Phosphate Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least Ether lipids are Lipids in which one or more of the Carbon Atoms on Glycerol is bonded to an Alkyl chain via an Ether linkage ^[25]

Archaea were originally described in extreme environments, such as hot springs, but have since been found in all types of habitats. A hot spring is a spring that is produced by the emergence of geothermally heated Groundwater from the earth's crust. ^[26] Only now are scientists beginning to appreciate how common archaea are in the environment, with crenarchaeota being the most common form of life in the ocean, dominating ecosystems below 150 m in depth. In taxonomy, the Crenarchaeota (Greek for "spring old quality" (also known as Crenarchaea or eocytes) are a phylum of the ^[27][28] These organisms are also common in soil and play a vital role in ammonia oxidation. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor ^[29]

Eukaryotes

Main article: Eukaryote

An amoeba, a typical eukaryotic microorganism

All living things which are individually visible to the naked eye are eukaryotes (with few exceptions, such as Thiomargarita namibiensis), including humans. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Amoeba (sometimes amœba or ameba, plural amoebae) is a Genus of Protozoa that moves Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Thiomargarita namibiensis ("Sulfur pearl of Namibia " is a Gram-negative Coccus Proteobacterium found in the ocean sediments Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus However, a large number of eukaryotes are also microorganisms. Unlike bacteria and archaea, eukaryotes contain organelles such as the cell nucleus, the Golgi apparatus and mitochondria in their cells. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have In Cell biology, an organelle (pronunciation /ɔː(rgəˡnɛl/ is a specialized subunit within a cell that has a specific function and is usually separately enclosed In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed The Golgi apparatus (also called the In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called The nucleus is an organelle which houses the DNA that makes up a cell's genome. Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known In classical genetics the genome of a Diploid Organism including Eukarya refers to a full set of chromosomes or genes in a Gamete, thereby DNA itself is arranged in complex chromosomes. A chromosome is an organized structure of DNA and Protein that is found in cells. ^[30] Mitochondria are organelles vital in metabolism as they are the site of the citric acid cycle and oxidative phosphorylation. Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. The citric acid cycle, also known as the tricarboxylic acid cycle ( TCA cycle) or the Krebs cycle, (or rarely the Szent-Györgyi–Krebs cycle Oxidative phosphorylation is a Metabolic pathway that uses energy released by the oxidation of Nutrients to produce Adenosine triphosphate (ATP They evolved from symbiotic bacteria and retain a remnant genome. This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek ^[31] Like bacteria, plant cells have cell walls, and contain organelles such as chloroplasts in addition to the organelles in other eukaryotes. Plant cells are eukaryotic cells that differ in several key respects from the cells of other eukaryotic Organisms Their distinctive features A cell wall is a tough flexible and sometimes fairly rigid layer surrounding a cell, located external to the Cell membrane, which provides the cell with structural Chloroplasts are Organelles found in Plant cells and eukaryotic Algae that conduct Photosynthesis. Chloroplasts produce energy from light by photosynthesis, and were also originally symbiotic bacteria. Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have ^[31]

Unicellular eukaryotes are those eukaryotic organisms that consist of a single cell throughout their life cycle. The cell is the structural and functional unit of all known living Organisms It is the smallest unit of an organism that is classified as living and is often called This qualification is significant since most multicellular eukaryotes consist of a single cell called a zygote at the beginning of their life cycles. Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions For other meanings see Zygote (disambiguation. A zygote (from Greek ζυγωτός zugōtos "joined" or "yoked" Microbial eukaryotes can be either haploid or diploid, and some organisms have multiple cell nuclei (see coenocyte). "Haplo" redirects here For the fictional character see The Death Gate Cycle. "Haplo" redirects here For the fictional character see The Death Gate Cycle. In Cell biology, the nucleus (pl nuclei; from Latin la ''nucleus'' or la ''nuculeus'' "little nut" or kernel is a membrane-enclosed A coenocyte is a Multinucleate cell. It can result from multiple nuclear divisions without accompanying Cell divisions or from cellular aggregation followed However, not all microorganisms are unicellular as some microscopic eukaryotes are made from multiple cells.

Protists

Main article: Protista

Of eukaryotic groups, the protists are most commonly unicellular and microscopic. Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually This is a highly diverse group of organisms that are not easy to classify. ^[32][33] Several algae species are multicellular protists, and slime molds have unique life cycles that involve switching between unicellular, colonial, and multicellular forms. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. Multicellular organisms are Organisms consisting of more than one cell, and having Differentiated cells that perform specialized functions Slime Mold is a broad term referring to amoeba-like organisms hence the name slime which feed on microorganisms in decaying vegetable matter hence the name Molds ^[34] The number of species of protozoa is uncertain, since we may have identified only a small proportion of the diversity in this group of organisms. ^[35][36]

A microscopic mite Lorryia formosa. Mites, along with Ticks belong to the subclass Acarina (also known as Acari and the class Arachnida Mites are among the most diverse and successful

Animals

Main article: Micro-animals

All animals are multicellular, but some are too small to be seen by the naked eye. Micro-animals are Animals that are microscopic and thus cannot be seen with the naked eye Microscopic arthropods include dust mites and spider mites. Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " The house dust mite (sometimes abbreviated by Allergists to HDM) is a cosmopolitan guest in Human habitation Spider mites are members of the Acari (mite family Tetranychidae, which includes about 1600 species Microscopic crustaceans include copepods and the cladocera, while many nematodes are too small to be seen with the naked eye. Structure of crustaceans As Arthropods crustaceans have a stiff Exoskeleton, which must be shed to allow the animal to grow ( Ecdysis or molting Copepods are a group of small Crustaceans found in the sea and nearly every freshwater habitat and they constitute the biggest source of protein in the oceans Cladocera or cladocerans are small Crustaceans commonly called Water fleas, part of the Class Branchiopoda. The nematodes or roundworms ( Phylum Nematoda from Greek (nema "thread" + -ode "like" are one of the most common Another particularly common group of microscopic animals are the rotifers, which are filter feeders that are usually found in fresh water. The rotifers make up a Phylum of microscopic and near-microscopic pseudocoelomate Animals They were first described by Rev Micro-animals reproduce both sexually and asexually and may reach new habitats as eggs that survive harsh environments that would kill the adult animal. However, some simple animals, such as rotifers and nematodes, can dry out completely and remain dormant for long periods of time. ^[37]

Fungi

Main article: Fungus

The fungi have several unicellular species, such as baker's yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe). A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Saccharomyces cerevisiae is a Species of Budding Yeast. It is perhaps the most useful Yeast owing to its use since ancient times Schizosaccharomyces pombe, also called "fission yeast" is a Species of Yeast. Some fungi, such as the pathogenic yeast Candida albicans, can undergo phenotypic switching and grow as single cells in some environments, and filamentous hyphae in others. Candida albicans is a Diploid Fungus (a form of Yeast) which is capable of mating but not of Meiosis, and a causal agent of Phenotypic switching (aka phenotypic dimorphism is switching between two cell-types A hypha (plural hyphae) is a long branching filamentous cell of a Fungus, and also of unrelated Actinobacteria. ^[38] Fungi reproduce both asexually, by budding or binary fission, as well by producing spores, which are called conidia when produced asexually, or basidiospores when produced sexually. Conidia, sometimes termed conidiospores, are asexual, non-motile Spores of a Fungus; they are also called mitospores due A basidiospore is a reproductive Spore produced by Basidiomycete Fungi.

Plants

Main article: Plant

The green algae are a large group of photosynthetic eukaryotes that include many microscopic organisms. Plants are living Organisms belonging to the kingdom Plantae. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Although some green algae are classified as protists, others such as charophyta are classified with embryophyte plants, which are the most familiar group of land plants. Protists (ˈproʊtɨst are a diverse group of eukaryotic Microorganisms Historically protists were treated as the kingdom Protista but this The Charophyta are a division of Green algae, including the closest relatives of the Embryophyte plants The embryophytes are the most familiar group of Plants They include Trees Flowers Ferns Mosses and various other green Algae can grow as single cells, or in long chains of cells. The green algae include unicellular and colonial flagellates, usually but not always with two flagella per cell, as well as various colonial, coccoid, and filamentous forms. Flagellates are cells with one or more whip-like organelles called flagella. A flagellum ( plural flagella) is a tail-like structure that projects from the Cell body of certain Prokaryotic and Eukaryotic cells and it Staphylococcus aureus Gramjpg|thumb|300px| Staphylococcus bacteria]] Cocci (singular - coccus, from the Latin coccinus (scarlet and derived from the In the Charales, which are the algae most closely related to higher plants, cells differentiate into several distinct tissues within the organism. The Charales are Algae in the division Charophyta. They are green plants believed to be the closest relatives of the green land plants. There are about 6000 species of green algae. ^[39]

Habitats and ecology

Microorganisms are found in almost every habitat present in nature. A habitat (which is Latin for "it inhabits" is an Ecological or environmental area that is inhabited by a particular Species. Even in hostile environments such as the poles, deserts, geysers, rocks, and the deep sea, some types of microorganisms have adapted to the extreme conditions and sustained colonies; these organisms are known as extremophiles. A geographical pole, or geographic pole, is either of two fixed points on the surface of a spinning body or Planet, at 90 degrees from the Equator, based A desert is a Landscape or region that receives very little precipitation. A geyser is a Hot spring characterized by intermittent discharge of water ejected turbulently and accomplished by a vapour phase In Geology, rock is a naturally occurring aggregate of Minerals and/or Mineraloids The Earth's outer solid layer the ‘ Lithosphere The deep sea, or deep layer, is the lowest layer in the Ocean, existing below the Thermocline, at a depth of 1000 fathoms or more An extremophile is an Organism that thrives in and may even require Physically or Geochemically extreme conditions that are detrimental to the Extremophiles have been isolated from rocks as much as 7 kilometres below the earth's surface,^[40] and it has been suggested that the amount of living organisms below the earth's surface may be comparable with the amount of life on or above the surface. ^[20] Extremophiles have been known to survive for a prolonged time in a vacuum, and can be highly resistant to radiation, which may even allow them to survive in space. This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays ^[41] Many types of microorganisms have intimate symbiotic relationships with other larger organisms; some of which are mutually beneficial (mutualism), while others can be damaging to the host organism (parasitism). This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek Mutualism is a Biological interaction between individuals of two different Species, where both individuals derive a fitness benefit for example increased In Biology, a host is an organism that harbors a Virus or Parasite, or a mutual or Commensal Symbiont, typically providing nourishment Parasitism is a type of symbiotic relationship between Organisms of different Species. If microorganisms can cause disease in a host they are known as pathogens. A disease is an abnormal condition of an organism that impairs bodily functions and can be deadly A pathogen (from Greek πάθος pathos "suffering passion" and γἰγνομαι (γεν- gignomai (gen- "I give birth to" infectious

Extremophiles

Main article: Extremophile

Extremophiles are microorganisms which have adapted so that they can survive and even thrive in conditions that are normally fatal to most lifeforms. An extremophile is an Organism that thrives in and may even require Physically or Geochemically extreme conditions that are detrimental to the An extremophile is an Organism that thrives in and may even require Physically or Geochemically extreme conditions that are detrimental to the For example, some species have been found in the following extreme environments:

• Temperature: as high as 130 °C (266 °F),^[42] as low as −17 °C (1. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature 4 °F)^[43]
• Acidity/alkalinity: less than pH 0,^[44] up to pH 11. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are Alkalinity or AT is a measure of the ability of a solution to neutralize acids to the Equivalence point of carbonate or bicarbonate pH is the measure of the acidity or alkalinity of a Solution. 5^[45]
• Salinity: up to saturation^[46]
• Pressure: up to 1,000-2,000 atm, down to 0 atm (e. Salinity is the Saltiness or dissolved salt content of a body of Water. Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface The Standard atmosphere is an international reference pressure defined as 101325 Pa and formerly used as unit of Pressure (symbol atm g. vacuum of space)^[47]
• Radiation: up to 5kGy^[48]

Extremophiles are significant in different ways. This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. Outer space, often simply called space, comprises the relatively empty regions of the Universe outside the escape velocities of Celestial bodies. Image talkNew_radiation_symbol_ISO_21482svg for details --> Ionizing radiation The gray (symbol Gy is the SI unit of absorbed radiation dose. They extend terrestrial life into much of the Earth's hydrosphere, crust and atmosphere, their specific evolutionary adaptation mechanisms to their extreme environment can be exploited in bio-technology, and their very existence under such extreme conditions increases the potential for extraterrestrial life. A hydrosphere (from Greek ύδωρ - hydor, " Water " + σφαίρα - sphaira, " Sphere " In Geology, a crust is the outermost solid shell of a planet or moon Biotechnology is Technology based on Biology, especially when used in Agriculture, Food science, and Medicine. Extraterrestrial life is Life originating outside of the Earth. ^[49]

Soil microbes

The nitrogen cycle in soils depends on the fixation of atmospheric nitrogen. The nitrogen cycle is the Biogeochemical cycle that describes the transformations of Nitrogen and nitrogen-containing compounds in nature One way this can occur is in the nodules in the roots of legumes that contain symbiotic bacteria of the genera Rhizobium, Mesorhizobium, Sinorhizobium, Bradyrhizobium, and Azorhizobium. A legume is a Plant in the family Fabaceae (or Leguminosae or a Fruit of these specific plants ^[50]

Symbiotic microbes

Symbiotic microbes

Importance

Microorganisms are vital to humans and the environment, as they participate in the Earth's element cycles such as the carbon cycle and nitrogen cycle, as well as fulfilling other vital roles in virtually all ecosystems, such as recycling other organisms' dead remains and waste products through decomposition. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the Biosphere, Pedosphere, Geosphere, Hydrosphere, and The nitrogen cycle is the Biogeochemical cycle that describes the transformations of Nitrogen and nitrogen-containing compounds in nature An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical ( Decomposition (or spoilage) refers to the break down of tissue of a formerly living Organism into simpler forms of matter Microbes also have an important place in most higher-order multicellular organisms as symbionts. This article is about the biological phenomenon for other uses see Symbiosis (disambiguation The term symbiosis (from the Greek Many blame the failure of Biosphere 2 on an improper balance of microbes. Biosphere 2 is a 314-acre (127 ha) structure originally built to be an artificial closed ecological system in Oracle, Arizona ( USA

Use in food

Main article: Fermentation (food)

Microorganisms are used in brewing, winemaking, baking, pickling and other food-making processes. Fermentation in Food processing typically refers to the conversion of Sugar to Alcohol using Yeast under Anaerobic conditions Brewing is the production of Alcoholic beverage and Alcohol fuel through fermentation. Winemaking, or vinification, is the production of Wine, starting with selection of the Grapes and ending with bottling the finished wine Baking is the technique of prolonged Cooking of Food by dry heat acting by conduction, and not by radiation, normally in an Oven, Pickling, also known as brining or corning, is the process of preserving Food by Anaerobic fermentation in Brine (a solution Food is any substance usually composed primarily of Carbohydrates Fats water and/or Proteins that can be eaten or drunk by an

They are also used to control the fermentation process in the production of cultured dairy products such as yogurt and cheese. Fermentation in Food processing typically refers to the conversion of Sugar to Alcohol using Yeast under Anaerobic conditions Dairy products are generally defined as Foodstuffs produced from Milk. Yoghurt, yogurt, yoghourt, youghurt or yogourt (see spelling below is a Cheese is a Food made from Milk, usually the milk of cows, Buffalo, Goats or sheep, by coagulation. The cultures also provide flavour and aroma, and inhibit undesirable organisms. ^[51]

Use in water treatment

Main article: Sewage treatment

Microbes are used in the biological treatment of sewage and industrial waste effluents. Sewage treatment, or domestic wastewater treatment, is the process of removing Contaminants from Wastewater, both Runoff ( Effluents .

Use in energy

Main article: Ethanol fermentation

Microbes are used in fermentation to produce ethanol. See also Fermentation (biochemistry Ethanol fermentation is the biological process by which sugars such as Glucose, Fructose, and Sucrose

Use in science

Microbes are also essential tools in biotechnology, biochemistry, genetics, and molecular biology. Biotechnology is Technology based on Biology, especially when used in Agriculture, Food science, and Medicine. Biochemistry is the study of the chemical processes in living Organisms It deals with the Structure and function of cellular components such as Genetics (from Ancient Greek grc-Latn genetikos, “genitive” and that from grc-Latn genesis, “origin” a discipline of Biology, is Molecular biology is the study of Biology at a molecular level The yeasts (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are important model organisms in science, since they are simple eukaryotes that can be grown rapidly in large numbers and are easily manipulated. Saccharomyces cerevisiae is a Species of Budding Yeast. It is perhaps the most useful Yeast owing to its use since ancient times Schizosaccharomyces pombe, also called "fission yeast" is a Species of Yeast. A model organism is a Species that is extensively studied to understand particular biological Phenomena, with the expectation that discoveries made ^[52] They are particularly valuable in genetics, genomics and proteomics. Genetics (from Ancient Greek grc-Latn genetikos, “genitive” and that from grc-Latn genesis, “origin” a discipline of Biology, is Genomics is the study of an organism's entire Genome. The field includes intensive efforts to determine the entire DNA sequence of organisms and fine-scale Genetic Proteomics is the large-scale study of Proteins particularly their structures and functions. ^[53][54] Microbes can be harnessed for uses such as creating steroids and treating skin diseases. A microorganism (also spelled micro organism or micro-organism and also called a microbe) is an Organism that is Microscopic (usually Scientists are also considering using microbes for living fuel cells, and as a solution for pollution. A fuel cell is an electrochemical conversion device It produces electricity from Fuel (on the Anode side and an oxidant (on the

Use in warfare

Main article: Biological warfare

In the Middle Ages, dead corpses were thrown over walls during sieges, this meant that any bacteria carrying the disease that killed the person/creature would multiply in the vicinity of the opposing side. Biological warfare (BW — known as a germ warfare, biological weapons and bioweaponry — is the use of any Pathogen ( Bacterium

Importance in human health

Human digestion

Further information: Human flora#Human bacterial flora and human health

Microorganisms can form an endosymbiotic relationship with other, larger organisms. The human flora is the Microrganisms that constantly inhabit the Human body. An endosymbiont is any Organism that lives within the body or cells of another organism i For example, the bacteria that live within the human digestive system contribute to gut immunity, synthesise vitamins such as folic acid and biotin, and ferment complex indigestible carbohydrates. A vitamin is an Organic compound required as a Nutrient in tiny amounts by an Organism. Folic acid (also known as Vitamin M and Folacin) and Folate (the Anionic form are forms of the water-soluble Vitamin B9 Vitamin H redirects here In medical slang "vitamin H" may also refer to Haloperidol. Carbohydrates (from ' Hydrates of Carbon ' or saccharides ( Greek σάκχαρον meaning " Sugar " are the most ^[55]

Diseases and immunology

Main article: Pathogenic microbes

Microorganisms are the cause of many infectious diseases. Pathogenic microbes are Microbes that cause Infectious diseases This article is dedicated to human pathogenic microbes The organisms involved include pathogenic bacteria, causing diseases such as plague, tuberculosis and anthrax; protozoa, causing diseases such as malaria, sleeping sickness and toxoplasmosis; and also fungi causing diseases such as ringworm, candidiasis or histoplasmosis. Pathogenic bacteria are Bacteria that cause Infectious diseases. Bubonic plague is the best-known manifestation of the bacterial disease plague, caused by the bacterium Yersinia pestis (formerly known as Tuberculosis (abbreviated as TB for tubercle bacillus or T u' b' erculosis Bacillus --> is a common Anthrax is an acute Disease in humans and animals caused by the bacterium Bacillus anthracis which is highly lethal in some forms Malaria is a vector -borne Infectious disease caused by Protozoan Parasites It is widespread in tropical and subtropical regions including Sleeping sickness or human African trypanosomiasis is a Parasitic Disease of people and animals caused by Protozoa of species Toxoplasmosis is a Parasitic disease caused by the Protozoan Toxoplasma gondii. Ringworm (also called serpigo) is an infection of the skin characterized by a reddish to brownish raised or bumpy patch of skin that may be lighter in the center Candidiasis, commonly called yeast infection or thrush, is a Fungal infection (mycosis of any of the Candida species of which Histoplasmosis, also known as Darling's disease, is a Disease caused by the Fungus Histoplasma capsulatum which was discovered in However, other diseases such as influenza, yellow fever or AIDS are caused by pathogenic viruses, which are not living organisms and are not therefore microorganisms. Yellow fever (also called yellow jack, black vomit or sometimes American Plague) is an acute viral disease As of 2007, no clear examples of archaean pathogens are known,^[56] although a relationship has been proposed between the presence of some methanogens and human periodontal disease. ^[57]

Hygiene

Main article: Hygiene

Hygiene is the avoidance of infection or food spoiling by eliminating microorganisms from the surroundings. Hygiene refers to practices associated with ensuring good health and cleanliness An infection is the detrimental Colonization of a host Organism by a foreign Species. Food is any substance usually composed primarily of Carbohydrates Fats water and/or Proteins that can be eaten or drunk by an As microorganisms, particularly bacteria, are found practically everywhere, this means in most cases the reduction of harmful microorganisms to acceptable levels. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have However, in some cases it is required that an object or substance be completely sterile, i. e. devoid of all living entities and viruses. A virus (from the Latin virus meaning Toxin or Poison) is a sub-microscopic infectious agent that is unable A good example of this is a hypodermic needle. A hypodermic needle is a hollow needle commonly used with a Syringe to inject substances into the body

In food preparation microorganisms are reduced by preservation methods (such as the addition of vinegar), clean utensils used in preparation, short storage periods or by cool temperatures. Vinegar is an acidic liquid processed from the Fermentation of Ethanol in a process that yields its key ingredient Acetic acid (also called ethanoic acid If complete sterility is needed, the two most common methods are irradiation and the use of an autoclave, which resembles a pressure cooker. Irradiation is the process by which an item is exposed to Radiation. An autoclave is a pressurized device designed to heat aqueous solutions above their Boiling point at normal atmospheric pressure to achieve sterilization

There are several methods for investigating the level of hygiene in a sample of food, drinking water, equipment etc. Water samples can be filtrated through an extremely fine filter. This filter is then placed in a nutrient medium. A growth medium or culture medium is a liquid or gel designed to support the growth of Microorganisms or cells There are different types of media for Microorganisms on the filter then grow to form a visible colony. Harmful microorganisms can be detected in food by placing a sample in a nutrient broth designed to enrich the organisms in question. A growth medium or culture medium is a liquid or gel designed to support the growth of Microorganisms or cells There are different types of media for Various methods, such as selective media or PCR, can then be used for detection. A growth medium or culture medium is a liquid or gel designed to support the growth of Microorganisms or cells There are different types of media for The hygiene of hard surfaces, such as cooking pots, can be tested by touching them with a solid piece of nutrient medium and then allowing the microorganisms to grow on it. A growth medium or culture medium is a liquid or gel designed to support the growth of Microorganisms or cells There are different types of media for

There are no conditions where all microorganisms would grow, and therefore often several different methods are needed. For example, a food sample might be analyzed on three different nutrient mediums designed to indicate the presence of "total" bacteria (conditions where many, but not all, bacteria grow), molds (conditions where the growth of bacteria is prevented by e. A growth medium or culture medium is a liquid or gel designed to support the growth of Microorganisms or cells There are different types of media for The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have WikipediaManual_of_Style#National_varieties_of_English --> Molds (or The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have g. antibiotics) and coliform bacteria (these indicate a sewage contamination). In modern usage an antibiotic is a Chemotherapeutic agent with activity against Microorganisms such as Bacteria, fungi or Protozoa The Coliform Index is a rating of the purity of Water based on a count of fecal Bacteria. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have

In fiction

Microorganisms have frequently played an important part in science fiction, both as agents of disease, and as entities in their own right.

Some notable uses of microorganisms in fiction include:

• The War of the Worlds, where microorganisms play important thematic and plot-related roles. The War of the Worlds (1898 by H G Wells, is an early Science fiction Novel which describes an invasion of England by
• Fantastic Voyage, in which some scientists are miniaturised to microscopic size and observe micro-organisms from a new perspective
• Blood Music, in which a colony of microorganisms is given intelligence
• The Andromeda Strain, in which extraterrestrial microorganisms kill several people
• The White Plague, is created and released in vengeance by John Roe O'Neill for the death of his wife and children, it is designed to kill only women. Fantastic Voyage is a 1966 Science fiction film written by Harry Kleiner Blood Music is a Science fiction novel by Greg Bear (ISBN 0-7434-4496-5 Intelligence (also called intellect) is an Umbrella term used to describe a property of the Mind that encompasses many related abilities such as the capacities The Andromeda Strain (1969 by Michael Crichton, is a Techno-thriller Novel documenting the efforts of a team of scientists investigating The White Plague (1982 is a Science fiction novel by Frank Herbert.
• Twelve Monkeys, James Cole (Bruce Willis) searches for a pure germ in the past, which creates a deadly plague in the future. Also, Brad Pitt (as Jeffery Goines) discusses his germaphobia.

See also

• Biological warfare
• Biology
• Microbial intelligence
• Nanobacterium
• Petri dish
• Prokaryote
• Soil contamination
• Staining
• Bacteria

References

External links

• Our Microbial Planet A free poster from the National Academy of Sciences about the positive roles of microbes.
• "Uncharted Microbial World: Microbes and Their Activities in the Environment" Report from the American Academy of Microbiology
• Understanding Our Microbial Planet: The New Science of Metagenomics A 20-page educational booklet providing a basic overview of metagenomics and our microbial planet.
• Microbe News from Genome News Network
• Microbes Patent List Microbes Related Patents
• Medical Microbiology On-line textbook
• Through the microscope: A look at all things small On-line microbiology textbook by Timothy Paustian and Gary Roberts, University of Wisconsin-Madison