• 0-9
  • a
  • b
  • c
  • d
  • e
  • f
  • g
  • h
  • i
  • j
  • k
  • l
  • m
  • n
  • o
  • p
  • q
  • r
  • s
  • t
  • u
  • v
  • w
  • x
  • y
  • z
  • plasma (state of matter)

    Plasma, in physics, an electrically conducting medium in which there are roughly equal numbers of positively and negatively charged particles, produced when the atoms in a gas become ionized. It is sometimes referred to as the fourth state of matter, distinct from the solid, liquid, and gaseous

  • plasma arc gasification (waste treatment)

    Plasma arc gasification (PAG), waste-treatment technology that uses a combination of electricity and high temperatures to turn municipal waste (garbage or trash) into usable by-products without combustion (burning). Although the technology is sometimes confused with incinerating or burning trash,

  • plasma arc machining (machine tool technology)

    machine tool: Plasma arc machining (PAM): PAM is a method of cutting metal with a plasma-arc, or tungsten inert-gas-arc, torch. The torch produces a high-velocity jet of high-temperature ionized gas (plasma) that cuts by melting and displacing material from the workpiece. Temperatures obtainable in the plasma zone range…

  • plasma cell (biology)

    Plasma cell, short-lived antibody-producing cell derived from a type of leukocyte (white blood cell) called a B cell. B cells differentiate into plasma cells that produce antibody molecules closely modeled after the receptors of the precursor B cell. Once released into the blood and lymph, these

  • plasma cell mastitis (pathology)

    mastitis: …uncommon type of mastitis, called plasma cell mastitis, occurs most frequently in older women who have had a number of children and have a history of difficulty in nursing. It is sometimes difficult to distinguish from cancer of the breast. In this disease lymphatic fluids stagnate in the breast, and…

  • plasma cell myeloma (pathology)

    Multiple myeloma, malignant proliferation of cells within the bone marrow that usually occurs during middle age or later and increases in occurrence with age. Myelomas are slightly more common in males than in females and can affect any of the marrow-containing bones, such as the skull, the flat

  • plasma cosmology (theory)

    Hannes Alfvén: …an early supporter of “plasma cosmology,” a concept that challenges the big-bang model of the origin of the universe. Those who support the theory of plasma cosmology hold that the universe had no beginning (and has no forseeable end) and that plasma—with its electric and magnetic forces—has done more…

  • plasma display panel (electronics)

    television: Plasma display panels: Plasma display panels (PDPs) overcome some of the disadvantages of both CRTs and LCDs. They can be manufactured easily in large sizes (up to 125 cm, or 50 inches, in diagonal size), are less than 10 cm (4 inches) thick, and have…

  • plasma instability (physics)

    plasma: Containment: …to diffuse out of the plasma; this time is different for each type of configuration. Various types of instabilities can occur in plasma. These lead to a loss of plasma and a catastrophic decrease in containment time. The most important of these is called magnetohydrodynamic instability. Although an equilibrium state…

  • plasma jet (physics)

    plasma: Applications of plasmas: …high-density plasma mixture called a plasma jet to be ejected. It has many chemical and metallurgical applications.

  • plasma membrane (biology)

    Cell membrane, thin membrane that surrounds every living cell, delimiting the cell from the environment around it. Enclosed by this cell membrane (also known as the plasma membrane) are the cell’s constituents, often large, water-soluble, highly charged molecules such as proteins, nucleic acids,

  • plasma oscillation (physics)

    Plasma oscillation, in physics, the organized motion of electrons or ions in a plasma. Each particle in a plasma assumes a position such that the total force resulting from all the particles is zero, thus producing a uniform state with a net charge of zero. If an electron is moved from its

  • plasma physics (physics)

    Hannes Alfvén: …his essential contributions in founding plasma physics—the study of plasmas (ionized gases).

  • plasma protein (biochemistry)

    Globulin, one of the major classifications of proteins, which may be further divided into the euglobulins and the pseudoglobulins. The former group is insoluble in water but soluble in saline solutions and may be precipitated in water that has been half-saturated with a salt such as ammonium

  • plasma sheet (astronomy)

    geomagnetic field: Outer magnetic field: …sheet of particles called the plasma sheet. The plasma sheet has an inner boundary about 11 Re behind Earth. It also has upper and lower boundaries as shown. The projection of these boundaries onto the northern and southern portions of the atmosphere at about 67° magnetic latitude corresponds to two…

  • plasma sintering

    advanced ceramics: Rapid heating: …means of rapid heating are plasma sintering and microwave sintering. Plasma sintering takes place in an ionized gas. Energetic ionized particles recombine and deposit large amounts of energy on the surfaces of the ceramic being sintered. Extremely high sintering rates have been achieved with this method. In microwave sintering, electromagnetic…

  • plasma state (state of matter)

    Plasma, in physics, an electrically conducting medium in which there are roughly equal numbers of positively and negatively charged particles, produced when the atoms in a gas become ionized. It is sometimes referred to as the fourth state of matter, distinct from the solid, liquid, and gaseous

  • plasma tail (astronomy)

    comet: General considerations: The ion tail forms from the volatile gases in the coma when they are ionized by ultraviolet photons from the Sun and blown away by the solar wind. Ion tails point almost exactly away from the Sun and glow bluish in colour because of the presence…

  • plasma thromboplastin antecedent (biochemistry)

    hemophilia: …IX (hemophilia B) or of factor XI (hemophilia C); hemophilia B (also called Christmas disease), like hemophilia A, is sex-linked and occurs almost only in males, whereas hemophilia C may be transmitted by both males and females and is found in both sexes.

  • plasma thromboplastin component (biochemistry)

    hemophilia: …attributed to a deficiency of factor IX (hemophilia B) or of factor XI (hemophilia C); hemophilia B (also called Christmas disease), like hemophilia A, is sex-linked and occurs almost only in males, whereas hemophilia C may be transmitted by both males and females and is found in both sexes.

  • plasma-assisted chemical vapour deposition (chemical process)

    integrated circuit: Chemical methods: Another variation, known as plasma-enhanced (or plasma-assisted) chemical vapour deposition, uses low pressure and high voltage to create a plasma environment. The plasma causes the gases to react and precipitate at much lower temperatures of 300 to 350 °C (600 to 650 °F) and at faster rates, but this…

  • plasma-emission spectrometry (chemistry)

    mass spectrometry: High-frequency-produced plasma: …but was first used in plasma-emission spectrometry (optical and near optical). Samples are introduced by means of a carrier gas, typically argon, and ions result as from the direct-current arc but with very few molecular ions and with the absence of impurities introduced by source electrodes. Such discharges are generally…

  • plasma-enhanced chemical vapour deposition (chemical process)

    integrated circuit: Chemical methods: Another variation, known as plasma-enhanced (or plasma-assisted) chemical vapour deposition, uses low pressure and high voltage to create a plasma environment. The plasma causes the gases to react and precipitate at much lower temperatures of 300 to 350 °C (600 to 650 °F) and at faster rates, but this…

  • plasmalogen (chemistry)

    peroxisome: …of membrane lipids known as plasmalogens. In plant cells, peroxisomes carry out additional functions, including the recycling of carbon from phosphoglycolate during photorespiration. Specialized types of peroxisomes have been identified in plants, among them the glyoxysome, which functions in the conversion of fatty acids to carbohydrates.

  • plasmapause (atmospheric science)

    Plasmapause, portion of the magnetosphere that rotates with the Earth at about four Earth radii (approximately 26,000 km, or 16,000 miles); beyond this region there is a rapid decrease in electron concentrations, and their circulation pattern is quite different. Under very quiet solar conditions,

  • plasmid (microbiology)

    Plasmid, in microbiology, an extrachromosomal genetic element that occurs in many bacterial strains. Plasmids are circular deoxyribonucleic acid (DNA) molecules that replicate independently of the bacterial chromosome. They are not essential for the bacterium but may confer a selective advantage.

  • plasmin (biology)

    blood: Hemostasis: Plasmin is a proteolytic enzyme—a substance that causes breakdown of proteins—derived from an inert plasma precursor known as plasminogen. When clots are formed within blood vessels, activation of plasminogen to plasmin may lead to their removal. (For additional information about the mechanics and significance of…

  • plasminogen (biology)

    blood: Hemostasis: …inert plasma precursor known as plasminogen. When clots are formed within blood vessels, activation of plasminogen to plasmin may lead to their removal. (For additional information about the mechanics and significance of hemostasis, see bleeding and blood clotting.)

  • plasmodesma (plant anatomy)

    Plasmodesma, microscopic cytoplasmic canal that passes through plant-cell walls and allows direct communication of molecules between adjacent plant cells. Plasmodesmata are formed during cell division, when traces of the endoplasmic reticulum become caught in the new wall that divides the parent

  • plasmodesmata (plant anatomy)

    Plasmodesma, microscopic cytoplasmic canal that passes through plant-cell walls and allows direct communication of molecules between adjacent plant cells. Plasmodesmata are formed during cell division, when traces of the endoplasmic reticulum become caught in the new wall that divides the parent

  • plasmodial fan (mycology)

    Plasmodium, in fungi (kingdom Fungi), a mobile multinucleate mass of cytoplasm without a firm cell wall. A plasmodium is characteristic of the vegetative phase of true slime molds (Myxomycetes) and such allied genera as Plasmodiophora and Spongospora. The plasmodium of a slime mold is formed from

  • Plasmodiophora brassicae (chromist)

    clubroot: …by the funguslike soil pathogen Plasmodiophora brassicae. Affected plants are stunted and yellowed; they wilt during hot sunny days and partially recover at night. In the early stages roots are greatly distorted by a mass of small to large “clubs,” often spindle-like, but in a variety of shapes. Susceptible plants…

  • Plasmodiophorina (phylum of organisms)

    Plasmodiophoromycota, phylum of endoparasitic slime molds in the kingdom Chromista. Some scientists assign Plasmodiophoromycota to the kingdom Protista; the taxonomy of the group, however, remains contentious. Several species are economically significant plant pathogens, including Plasmodiophora

  • Plasmodiophoromycota (phylum of organisms)

    Plasmodiophoromycota, phylum of endoparasitic slime molds in the kingdom Chromista. Some scientists assign Plasmodiophoromycota to the kingdom Protista; the taxonomy of the group, however, remains contentious. Several species are economically significant plant pathogens, including Plasmodiophora

  • plasmodium (mycology)

    Plasmodium, in fungi (kingdom Fungi), a mobile multinucleate mass of cytoplasm without a firm cell wall. A plasmodium is characteristic of the vegetative phase of true slime molds (Myxomycetes) and such allied genera as Plasmodiophora and Spongospora. The plasmodium of a slime mold is formed from

  • Plasmodium (protozoan genus)

    Plasmodium, a genus of parasitic protozoans of the sporozoan subclass Coccidia that are the causative organisms of malaria. Plasmodium, which infects red blood cells in mammals (including humans), birds, and reptiles, occurs worldwide, especially in tropical and temperate zones. The organism is

  • Plasmodium falciparum (protozoan)

    blackwater fever: …with infection from the parasite Plasmodium falciparum. Blackwater fever has a high mortality. Its symptoms include a rapid pulse, high fever and chills, extreme prostration, a rapidly developing anemia, and the passage of urine that is black or dark red in colour (hence the disease’s name). The distinctive colour of…

  • Plasmodium knowlesi (protozoan)

    malaria: The course of the disease: malariae, and P. knowlesi. The most common worldwide is P. vivax. The deadliest is P. falciparum. In 2008 P. knowlesi, which was thought to infect primarily Old World monkeys and to occur only rarely in humans, was identified as a major cause of malaria in humans in…

  • Plasmodium malariae (protozoan)

    malaria: The course of the disease: ovale, P. malariae, and P. knowlesi. The most common worldwide is P. vivax. The deadliest is P. falciparum. In 2008 P. knowlesi, which was thought to infect primarily Old World monkeys and to occur only rarely in humans, was identified as a major cause of malaria…

  • Plasmodium ovale (protozoan)

    malaria: The course of the disease: vivax, P. ovale, P. malariae, and P. knowlesi. The most common worldwide is P. vivax. The deadliest is P. falciparum. In 2008 P. knowlesi, which was thought to infect primarily Old World monkeys and to occur only rarely in humans, was identified as a major cause…

  • Plasmodium reichenowi (protozoan)

    malaria: Evolution of malaria parasites in primates: …primates (other than humans) was P. reichenowi, which occurs in both chimpanzees and gorillas. This organism, first described between 1917 and 1920, was found to be very similar morphologically to P. falciparum, suggesting that the two must be closely related. However, subsequent studies conducted in the 1920s and ’30s demonstrated…

  • Plasmodium vivax (protozoan)

    malaria: The course of the disease: (single-celled) parasites: Plasmodium falciparum, P. vivax, P. ovale, P. malariae, and P. knowlesi. The most common worldwide is P. vivax. The deadliest is P. falciparum. In 2008 P. knowlesi, which was thought to infect primarily Old World monkeys and to occur only rarely in humans, was identified as a…

  • plasmogamy (reproduction)

    fungus: Sexual reproduction: Plasmogamy, the fusion of two protoplasts (the contents of the two cells), brings together two compatible haploid nuclei. At this point, two nuclear types are present in the same cell, but the nuclei have not yet fused. Karyogamy results in the fusion of these haploid…

  • plasmoid (physics)

    geomagnetic field: Expansion phase: …of plasma and field, or plasmoid, from the centre of the magnetotail. The plasmoid travels down the tail, collapsing the plasma sheet behind it.

  • plasmon state (physics)

    radiation: Excitation states: The plasmon state is a highly delocalized state formed collectively through Coulombian (electrostatic) interaction of weakly bound electrons. Energy losses, approximating 10–20 eV in most materials, resulting from formation of plasmon states are seen in the impact of electrons of a few tens of kilovolts energy…

  • Plasmopara viticola (chromist)

    Pierre-Marie-Alexis Millardet: Along with phylloxera came Plasmopara viticola, a downy mildew fungus that damaged fruits and vegetables, particularly grapes. Farmers for centuries in the Médoc area of France had sprinkled their vines with a thick mixture of copper sulfate, lime, and water, whose unappetizing appearance discouraged thieves from stealing the grapes.…

  • Plassey (India)

    Palashi, historic village, east-central West Bengal state, northeastern India. It lies just east of the Bhagirathi River, about 80 miles (130 km) north of Kolkata (Calcutta). Palashi was the scene of the Battle of Plassey, a decisive victory of British forces under Robert Clive over those of the

  • Plassey, Battle of (Indian history [1757])

    Battle of Plassey, (23 June 1757). Victory for the British East India Company in the Battle of Plassey was the start of nearly two centuries of British rule in India. For an event with such momentous consequences, it was a surprisingly unimpressive military encounter, the defeat of the Nawab of

  • plaster (building material)

    Plaster, a pasty composition (as of lime or gypsum, water, and sand) that hardens on drying and is used for coating walls, ceilings, and partitions. Plastering is one of the most ancient building techniques. Evidence indicates that primitive peoples plastered their reed or sapling shelters with

  • plaster mold casting

    George Segal: …Jersey), American sculptor of monochromatic cast plaster figures often situated in environments of mundane furnishings and objects.

  • plaster of paris

    Plaster of paris, quick-setting gypsum plaster consisting of a fine white powder (calcium sulfate hemihydrate), which hardens when moistened and allowed to dry. Known since ancient times, plaster of paris is so called because of its preparation from the abundant gypsum found near Paris. Plaster of

  • plaster print

    printmaking: Plaster print: Good proofs of an intaglio plate can be made by plaster casting, for fine plaster of paris will pick up the most delicate details. This method will produce a particularly attractive proof if the plate has deeply etched or engraved sections.

  • plasterboard (building material)

    Drywall, any of various large rigid sheets of finishing material used in drywall construction to face the interior walls of dwellings and other buildings. Drywall construction is the application of walls without the use of mortar or plaster. Drywall materials include plywood and wood pulp,

  • plastic (chemical compound)

    Plastic, polymeric material that has the capability of being molded or shaped, usually by the application of heat and pressure. This property of plasticity, often found in combination with other special properties such as low density, low electrical conductivity, transparency, and toughness, allows

  • plastic anisotropy (metallurgy)

    metallurgy: Metallurgy: …processing and composition is the plastic anisotropy ratio. When a segment of sheet is strained (i.e., elongated) in one direction, the thickness and width of the segment must shrink, since the volume remains constant. In an isotropic sheet the thickness and width show equal strain, but, if the grains of…

  • Plastic Art and Pure Plastic Art (essay by Mondrian)

    Piet Mondrian: Later years: …to publish his essay “Plastic Art and Pure Plastic Art,” Mondrian’s first essay in English, in the international publication Circle, of which Nicholson was coeditor. In this way, Mondrian’s ideas continued to gain an even broader audience. When Mondrian decided to leave Paris in 1938, under the shadow of…

  • plastic collision (physics)

    plasma: Plasma oscillations and parameters: In an inelastic collision, a fraction of the kinetic energy is transferred to the internal energy of the colliding particles. In an atom, for example, the electrons have certain allowed (discrete) energies and are said to be bound. During a collision, a bound electron may be excited—that…

  • plastic crystal (physics)

    liquid crystal: Symmetries of liquid crystals: These are the so-called plastic crystals. Many interesting liquid crystal phases are not listed in this table, including the discotic phase, consisting of disk-shaped molecules, and the columnar phases, in which translational symmetry is broken in not one but two spatial directions, leaving liquidlike order only along columns. The…

  • plastic deformation (mechanics)

    ice: Mechanical properties: This plastic deformation, or creep, is of great importance to the study of glacier flow. It involves two processes: intracrystalline gliding, in which the layers within an ice crystal shear parallel to each other without destroying the continuity of the crystal lattice, and recrystallization, in which…

  • plastic explosive (explosive)

    explosive: Picric acid and ammonium picrate: A series of plastic demolition explosives with great shattering power, designated Composition C-1 to Composition C-4, has had considerable publicity. These contain about 80 percent RDX combined with a mixture of various oils, waxes, and plasticizers. The only significant difference is in the temperature range through which they…

  • plastic fat

    carboxylic acid: Unsaturated aliphatic acids: Solid fats, obtained mostly from animal sources, have a high percentage of saturated fatty acids. Liquid fats (often called oils), obtained mainly from plant or fish sources, have a high percentage of unsaturated fatty acids. An exception is coconut oil, which, though obtained from a…

  • plastic flow (mechanics)

    ice: Mechanical properties: This plastic deformation, or creep, is of great importance to the study of glacier flow. It involves two processes: intracrystalline gliding, in which the layers within an ice crystal shear parallel to each other without destroying the continuity of the crystal lattice, and recrystallization, in which…

  • plastic forming (technology)

    traditional ceramics: Forming: The mechanisms of plastic forming and slip casting are described below.

  • plastic impact (physics)

    plasma: Plasma oscillations and parameters: In an inelastic collision, a fraction of the kinetic energy is transferred to the internal energy of the colliding particles. In an atom, for example, the electrons have certain allowed (discrete) energies and are said to be bound. During a collision, a bound electron may be excited—that…

  • plastic laminate (chemical compound)

    furniture industry: Other materials: Plastic laminate, widely used for table and other tops, is obtainable in various colours and designs and in photographically reproduced natural wood grain. Its advantages are that it resists all liquid stains, is largely heat proof against burn marks, is mark free, and is easily…

  • plastic limit (geology)

    clay mineral: Clay-water relations: …water content increases, clays become plastic and then change to a near-liquid state. The amounts of water required for the two states are defined by the plastic and liquid limits, which vary with the kind of exchangeable cations and the salt concentration in the adsorbed water. The plasticity index (PI),…

  • Plastic Man (comic-book character)

    Plastic Man, fictional superhero. Plastic Man was one of the real stars of the Quality Comics lineup of superheroes in comics’ Golden Age (1938–1954), thanks to the madcap genius of his creator, Jack Cole. Cole had led a colourful life, including cycling across America at the age of 18, before

  • Plastic Ono Band (album by Lennon)

    John Lennon: … (1968) through the solo debut Plastic Ono Band (1970) through his half of Double Fantasy (1980)—reflects Ono’s belief in art without artifice. Whether or not they actually eschewed artifice, that was one impression they strove to create.

  • plastic pollution

    Plastic pollution, accumulation in the environment of synthetic plastic products to the point where they create problems for wildlife and their habitats as well as for human populations. In 1907 the invention of Bakelite brought about a revolution in materials by introducing truly synthetic plastic

  • plastic scintillator (device)

    radiation measurement: Organic scintillators: …is added to liquid or plastic scintillators to act as a wave shifter, which absorbs the primary light from the organic fluor and re-radiates the energy at a longer wavelength more suitable for matching the response of photomultiplier tubes or photodiodes. Plastic scintillators are commercially available in sheets or cylinders…

  • plastic strain (mechanics)

    metallurgy: Testing mechanical properties: …until it begins to undergo plastic strain (i.e., strain that is not recovered when the sample is unloaded). This stress is called the yield stress. It is a property that is the same for various samples of the same alloy, and it is useful in designing structures since it predicts…

  • plastic surgery

    Plastic surgery, the functional, structural, and aesthetic restoration of all manner of defects and deformities of the human body. The term plastic surgery stems from the Greek word plastikos, meaning “to mold” or “to form.” Modern plastic surgery has evolved along two broad themes: reconstruction

  • plasticity (physics)

    Plasticity, ability of certain solids to flow or to change shape permanently when subjected to stresses of intermediate magnitude between those producing temporary deformation, or elastic behaviour, and those causing failure of the material, or rupture (see yield point). Plasticity enables a solid

  • plasticity index (chemistry)

    clay mineral: Clay-water relations: The plasticity index (PI), the difference between the two limits, gives a measure for the rheological (flowage) properties of clays. A good example is a comparison of the PI of montmorillonite with that of allophane or palygorskite. The former is considerably greater than either of the…

  • plasticity, neural (biology)

    Neuroplasticity, capacity of neurons and neural networks in the brain to change their connections and behaviour in response to new information, sensory stimulation, development, damage, or dysfunction. Although neural networks also exhibit modularity and carry out specific functions, they retain

  • plasticity, phenotypic (genetics)

    moss animal: Zooids: …species exhibit a phenomenon called phenotypic plasticity. These species have the ability to alter the form of newly generated zooids in response to pressures of increased predation or competition. Such environmental cues may cause zooids to express different genetic characters, such as armoured or spined outer coverings, than they otherwise…

  • plasticized polyvinyl chloride (chemical compound)

    major industrial polymers: Polyvinyl chloride (PVC): …obtained what is now called plasticized PVC. The discovery of this flexible, inert product was responsible for the commercial success of the polymer. Another route to a flexible product was copolymerization: in 1930 the Union Carbide Corporation introduced the trademarked polymer Vinylite, a copolymer of vinyl chloride and vinyl acetate…

  • plasticized PVC (chemical compound)

    major industrial polymers: Polyvinyl chloride (PVC): …obtained what is now called plasticized PVC. The discovery of this flexible, inert product was responsible for the commercial success of the polymer. Another route to a flexible product was copolymerization: in 1930 the Union Carbide Corporation introduced the trademarked polymer Vinylite, a copolymer of vinyl chloride and vinyl acetate…

  • plasticizer (technology)

    rubber: Plasticizers and processing aids: Liquids are added to elastomer mixes in order to soften and plasticize the compound, either in processing or later in use. For example, elastomers with high glass transition temperatures (and correspondingly slow molecular motions) can be improved by adding low-temperature plasticizers—i.e.,…

  • plasticoviscous deformation (mechanics)

    rock: Stress-strain relationships: A plasticoviscous material exhibits elastic behaviour for initial stress (as in plastic behaviour), but after the yield point stress is reached, it flows like a viscous fluid.

  • plastid (biology)

    protist: Respiration and nutrition: Thus, the plastids of algal protists function like the chloroplasts of plants with respect to photosynthesis, and, when present, the mitochondria function as the site where molecules are broken down to release chemical energy, carbon dioxide, and water. The basic difference between the unicellular protists and the…

  • Plastino, Al (American comic book artist)
  • Plastíras, Nikólaosí (Greek general)

    Greece: From the National Schism to dictatorship: Nikólaos Plastíras, a staunch supporter of Venizélos and the mastermind behind the 1922 coup, sought to restore Venizélos to power by force. His coup was unsuccessful and was subsequently followed by an assassination attempt on Venizélos. The political arena was once again split between supporters…

  • plastisol (chemical compound)

    polyvinyl chloride: The resultant fluid, called a plastisol, will remain liquid even after cooling but will solidify into a gel upon reheating. Plastisols can be made into products by being spread on fabric or cast into molds. Flexible gloves can be made by dipping a hand-shaped form into plastisol, and hollow objects…

  • plastocyanin (chemical compound)

    photosynthesis: Proteins: A copper-containing protein called plastocyanin (PC) carries electrons at one point in the electron transport chain. PC molecules are water soluble and can move through the inner space of the thylakoids, carrying electrons from one place to another.

  • plastoquinone (chemical compound)

    photosynthesis: Quinones: Small molecules called plastoquinones are found in substantial numbers in the lamellae. Like the cytochromes, quinones have important roles in carrying electrons between the components of the light reactions. Since they are lipid soluble, they can diffuse through the membrane. They can carry one or two electrons, and,…

  • plastron (biology)

    turtle: …(carapace) and a bottom (plastron). The carapace and plastron are bony structures that usually join one another along each side of the body, creating a rigid skeletal box. This box, composed of bone and cartilage, is retained throughout the turtle’s life. Because the shell is an integral part of…

  • plastron respiration (physiology)

    respiratory system: Trachea: …forms below it, creating a plastron, or air shell, into which the tracheae open. As respiration proceeds, the outward diffusion of nitrogen and consequent shrinkage of the gas space are prevented by the surface tension—a condition manifested by properties that resemble those of an elastic skin under tension—between the closely…

  • Plaszow (concentration camp, Poland)

    Plaszow, Nazi German concentration camp near Kraków, in German-occupied Poland, used chiefly as a forced-labour centre. Opened in June 1942, the camp was the main forced-labour camp for Jews rounded up from the general region of Kraków and, later, for Jews from Hungary. At its peak, it held some

  • Płaszów (concentration camp, Poland)

    Plaszow, Nazi German concentration camp near Kraków, in German-occupied Poland, used chiefly as a forced-labour centre. Opened in June 1942, the camp was the main forced-labour camp for Jews rounded up from the general region of Kraków and, later, for Jews from Hungary. At its peak, it held some

  • plat de porc aux bananes vertes, Un (work by Schwarz-Bart)

    André Schwarz-Bart: …West Indian wife, Simone, published Un Plat de porc aux bananes vertes (“A Plate of Pork with Green Bananas”). It was the first of a cycle of novels in which the authors approach the problem of racism, tracing the historical misfortunes of blacks. Schwarz-Bart wrote La Mulâtresse Solitude (1972; A…

  • Plata, Río de la (river, Puerto Rico)

    La Plata River, river in east-central Puerto Rico, rising on the western slope of Mount Santa (2,963 feet [903 metres]), a peak of the Sierra de Cayey. Part of the stream is impounded by Lake Carite; the reservoir’s outlet diverts waters for a series of hydroelectric stations on the Guamaní River

  • Plata, Río de la (estuary, South America)

    Río de la Plata, (Spanish: “River of Silver”) a tapering intrusion of the Atlantic Ocean on the east coast of South America between Uruguay to the north and Argentina to the south. While some geographers regard it as a gulf or as a marginal sea of the Atlantic, and others consider it to be a river,

  • Platacanthomyinae (rodent)

    Asian tree mouse, (subfamily Platacanthomyinae), any of three species of small rodents found only in a few tropical forests of India and continental Southeast Asia. The Malabar spiny tree mouse (Platacanthomys lasiurus) lives only in the old-growth rainforests of southwestern India. Nocturnal and

  • Platacanthomys lasiurus (rodent)

    Asian tree mouse: The Malabar spiny tree mouse (Platacanthomys lasiurus) lives only in the old-growth rainforests of southwestern India. Nocturnal and arboreal, it builds nests in tree cavities and eats fruits and nuts. The animal is named for its flat, grooved spines and bristles, which are tipped with white and…

  • Plataea (ancient city, Greece)

    Plataea, ancient city of Boeotia, Greece. It was situated on a triangular ledge 1,000 feet (300 m) above sea level, on the northern side of Mount Cithaeron below the modern village of Plataiaí. It was well positioned in time of war to threaten the main road from Thebes to the Isthmus of Corinth,

  • Plataea, Battle of (Greek history [479 bce])

    Battle of Plataea, (July 479 bce). Following the Greek naval success at the Battle of Salamis in 480 bce, Persian King Xerxes left Greece with much of his army. However, his general, Mardonius, remained in northern Greece to continue the fight. The war’s deciding encounter at Plataea the next

  • Platalea alba (bird)

    spoonbill: Others are the African spoonbill (P. alba); the lesser spoonbill (P. minor) of eastern Asia; and two Australian species, the royal, or black-billed, spoonbill (P. regia), and the yellow-billed, or yellow-legged, spoonbill (P. flavipes).

  • Platalea flavipes (bird)

    spoonbill: regia), and the yellow-billed, or yellow-legged, spoonbill (P. flavipes).

  • Platalea leucorodia (bird)

    spoonbill: The European spoonbill (Platalea leucorodia) is a crested white bird about 60 cm long with cinnamon buff on the foreneck. It breeds in marshes of central and southern Europe and Asia, south to Egypt, India, and Taiwan. Others are the African spoonbill (P. alba); the lesser…

  • Your preference has been recorded
    Check out Britannica's new site for parents!
    Subscribe Today!