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  • phone (linguistics)

    linguistics: Phonology: …sounds considered as units of phonetic analysis in this article are called phones, and, following the normal convention, are represented by enclosing the appropriate alphabetic symbol in square brackets. Thus, [p] will refer to a p sound (i.e., what is described more technically as a voiceless, bilabial stop); and [pit]…

  • phone

    Telephone, an instrument designed for the simultaneous transmission and reception of the human voice. The telephone is inexpensive, is simple to operate, and offers its users an immediate, personal type of communication that cannot be obtained through any other medium. As a result, it has become

  • Phone Call from a Stranger (film by Negulesco [1952])

    Jean Negulesco: Millionaire and Three Coins: Better received was the suspenseful Phone Call from a Stranger (1952), which follows a plane crash survivor as he visits the families of those who were killed; Bette Davis, Shelley Winters, Michael Rennie, and Gary Merrill headed a strong cast. After the historical adventure Lydia Bailey (1952), Negulesco made Lure…

  • phone phreaking (communications)

    Phreaking, fraudulent manipulation of telephone signaling in order to make free phone calls. Phreaking involved reverse engineering the specific tones used by phone companies to route long distance calls. By emulating those tones, “phreaks” could make free calls around the world. Phreaking largely

  • phone tapping

    electronic eavesdropping: …of electronic eavesdropping has been wiretapping, which monitors telephonic and telegraphic communication. It is legally prohibited in virtually all jurisdictions for commercial or private purposes.

  • phoneme (linguistics)

    Phoneme, in linguistics, smallest unit of speech distinguishing one word (or word element) from another, as the element p in “tap,” which separates that word from “tab,” “tag,” and “tan.” A phoneme may have more than one variant, called an allophone (q.v.), which functions as a single sound; for

  • phonemic writing (linguistics)

    language: Evolution of writing systems: …vowel signs, thus producing an alphabet, a set of letters standing for consonants and vowels. The Greek alphabet spread over the ancient Greek world, undergoing minor changes. From a Western version sprang the Latin (Roman) alphabet. Also derived from the Greek alphabet, the Cyrillic alphabet was devised in the 9th…

  • phonemics (linguistics)

    Phonemics, in linguistics, the study of the phonemes and phonemic system of a language. For linguists who analyze phonological systems wholly in terms of the phoneme, phonemics is coextensive with phonology

  • phonemography (linguistics)

    language: Evolution of writing systems: …vowel signs, thus producing an alphabet, a set of letters standing for consonants and vowels. The Greek alphabet spread over the ancient Greek world, undergoing minor changes. From a Western version sprang the Latin (Roman) alphabet. Also derived from the Greek alphabet, the Cyrillic alphabet was devised in the 9th…

  • phonetic alphabet (linguistics)

    cuneiform: Origin and character of cuneiform: …word writing to a partial phonetic script. Thus, for example, the picture of a hand came to stand not only for Sumerian šu (“hand”) but also for the phonetic syllable šu in any required context. Sumerian words were largely monosyllabic, so the signs generally denoted syllables, and the resulting mixture…

  • phonetic transfer (etymology)

    toponymy: Phonetic transfer is the most common means of place-name transfer between languages. This involves the spoken transfer of a place-name from one language to another. Little or no knowledge of the language from which the place-name originated is required. A person will listen to the…

  • phonetics (linguistics)

    Phonetics, the study of speech sounds and their physiological production and acoustic qualities. It deals with the configurations of the vocal tract used to produce speech sounds (articulatory phonetics), the acoustic properties of speech sounds (acoustic phonetics), and the manner of combining

  • Phoneutria fera (spider)

    wandering spider: >Phoneutria fera and P. nigriventer, are sometimes also referred to as banana spiders because they are frequently found on banana leaves. They have an aggressive defense posture, in which they raise their front legs straight up into the air. Phoneutria are poisonous to humans. Their…

  • Phoneutria nigriventer (spider)

    wandering spider: …wandering spiders, Phoneutria fera and P. nigriventer, are sometimes also referred to as banana spiders because they are frequently found on banana leaves. They have an aggressive defense posture, in which they raise their front legs straight up into the air. Phoneutria are poisonous to humans. Their venom is toxic…

  • Phong shading (art)

    computer graphics: Shading and texturing: In Phong shading each pixel takes into account any texture and all light sources. It generally gives more realistic results but is somewhat slower.

  • phoniatrics (medicine)

    speech disorder: Development of speech correction: …voice pathology as logopedics and phoniatrics with its medical orientation subsequently reached many other civilized nations, notably in Japan and on the South American continent. The national organizations in most of these areas are now represented in the International Association of Logopedics and Phoniatrics, which was founded in Vienna in…

  • phonics (education)

    Phonics, Method of reading instruction that breaks language down into its simplest components. Children learn the sounds of individual letters first, then the sounds of letters in combination and in simple words. Simple reading exercises with a controlled vocabulary reinforce the process.

  • phonocardiogram (medicine)

    Phonocardiography, diagnostic technique that creates a graphic record, or phonocardiogram, of the sounds and murmurs produced by the contracting heart, including its valves and associated great vessels. The phonocardiogram is obtained either with a chest microphone or with a miniature sensor in the

  • phonocardiography (medicine)

    Phonocardiography, diagnostic technique that creates a graphic record, or phonocardiogram, of the sounds and murmurs produced by the contracting heart, including its valves and associated great vessels. The phonocardiogram is obtained either with a chest microphone or with a miniature sensor in the

  • Phonofilm (film)

    Phonofilm, system used in the 1920s to provide sound synchronized with motion pictures. A sound track was photographically recorded on the film by a beam of light modulated by the sound waves. The sound was reproduced during projection by directing a beam of light through the sound track onto a

  • phonogram (linguistics)

    Egyptian language: Writing: … system was both logographic and phonetic. Logographic signs represent words, and phonetic signs represent one to three consonants (vowels not being of concern). Phonetic signs are used without regard for their original meaning. Thus, because the logograph for ‘house’ also signifies the sound pr, it is used to write the…

  • phonograph (instrument)

    Phonograph, instrument for reproducing sounds by means of the vibration of a stylus, or needle, following a groove on a rotating disc. A phonograph disc, or record, stores a replica of sound waves as a series of undulations in a sinuous groove inscribed on its rotating surface by the stylus. When

  • phonograph disc

    sound recording: The phonograph disc: A monaural phonograph record makes use of a spiral 90° V-shaped groove impressed into a plastic disc. As the record revolves at 33 13 rotations per minute, a tiny “needle,” or stylus, simultaneously moves along the groove and vibrates back and forth parallel to the surface…

  • phonograph record

    sound recording: The phonograph disc: A monaural phonograph record makes use of a spiral 90° V-shaped groove impressed into a plastic disc. As the record revolves at 33 13 rotations per minute, a tiny “needle,” or stylus, simultaneously moves along the groove and vibrates back and forth parallel to the surface…

  • phonolite (rock)

    Phonolite, any member of a group of extrusive igneous rocks (lavas) that are rich in nepheline and potash feldspar. The typical phonolite is a fine-grained, compact igneous rock that splits into thin, tough plates which make a ringing sound when struck by a hammer, hence the rock’s name. The most

  • phonological change (linguistics)

    Dravidian languages: Proto-Dravidian sound changes: Several sound changes are found in all Dravidian languages in all subgroups. To be so widely distributed, these changes must have been prevalent in the parent language itself.

  • phonological conditioning (linguistics)

    linguistics: Morphology: …them is determined by the phonological structure of the preceding morph. Thus the choice is phonologically conditioned.

  • phonological loop (psychology)

    memory: Patterns of acquisition in working memory: …supported by two systems: the phonological loop, which processes aural information, and the visuospatial sketch pad, which processes visual and spatial information. When information is acquired aurally, the brain encodes the information according to the way it sounds. A person who hears a spoken telephone number and retains the information…

  • phonological modification (linguistics)

    Dravidian languages: Proto-Dravidian sound changes: Several sound changes are found in all Dravidian languages in all subgroups. To be so widely distributed, these changes must have been prevalent in the parent language itself.

  • phonology (linguistics)

    Phonology, study of the sound patterns that occur within languages. Some linguists include phonetics, the study of the production and description of speech sounds, within the study of phonology. Diachronic (historical) phonology examines and constructs theories about the changes and modifications

  • phonon (physics)

    Phonon, in condensed-matter physics, a unit of vibrational energy that arises from oscillating atoms within a crystal. Any solid crystal, such as ordinary table salt (sodium chloride), consists of atoms bound into a specific repeating three-dimensional spatial pattern called a lattice. Because the

  • phonoreception

    Sound reception, response of an organism’s aural mechanism, the ear, to a specific form of energy change, or sound waves. Sound waves can be transmitted through gases, liquids, or solids, but the hearing function of each species is particularly (though not exclusively) sensitive to stimuli from one

  • Phony War (European history)

    Phony War, (1939–40) a name for the early months of World War II, marked by no major hostilities. The term was coined by journalists to derisively describe the six-month period (October 1939–March 1940) during which no land operations were undertaken by the Allies or the Germans after the German

  • Phonygammus keraudrenii (bird)

    bird-of-paradise: The trumpetbird (Phonygammus keraudrenii) is 25 to 32 cm (10 to 12.5 inches) long and has head tufts as well as pointed neck feathers. It is named for the male’s loud call. Others having special names include sicklebills and standardwings.

  • Phoradendron (plant)

    plant disease: Mistletoe: There are three important types: American (Phorodendron species), European (Viscum album), and dwarf (Arceuthobium species). All produce sticky seeds spread by birds. American mistletoe, restricted to the Americas, is best known for its ornamental and sentimental uses at Christmastime. The leafy, bushy evergreen masses, up to one metre or more…

  • Phoradendron serotinum (plant)

    mistletoe: …American counterpart, the Eastern, or oak, mistletoe (Phoradendron serotinum), also parasitizes many deciduous trees, including oaks.

  • phorate (pesticide)

    Phorate, generically, a powerful pesticide effective against insects, mites, and nematodes. It is a systemic insecticide that acts by inhibiting cholinesterases, enzymes involved in transmitting nerve impulses. Chemically, it is an organophosphate, O,O-diethyl S-(ethylthio)methyl

  • phorbeia (strap)

    aulos: …the Greeks often tied a phorbeia (Latin: capistrum), or leather strap, across the cheeks for additional support. During the Classical period auloi were equal in length, but this was not often true in later versions. Classical writers make few clear references to technical details for modern scholars to determine further…

  • phoresy (zoology)

    Phoresy, transportation of one organism by another, more mobile one. The term is not applied to a parasitic relationship, but minute parasites may use this means of transport to colonize new hosts. For example, feather lice accomplish phoresy by clinging to the body hairs of blood-sucking

  • phorid fly (insect)

    beekeeping: Colony collapse disorder: …species of Nosema, and the phorid fly Apocephalus borealis. However, scientists have not reached a definitive conclusion on whether a single pathogen is the root cause of the disorder, and many scientists suspect that a combination of factors are involved, such as a weakened immune system, brought on by colony…

  • Phoridae (insect)

    Humpbacked fly, (family Phoridae), any of numerous species of tiny, dark-coloured flies with humped backs that are in the fly order, Diptera, and can be found around decaying vegetation. Larvae may be scavengers, parasites, or commensals in ant and termite nests. Some species have reduced or no

  • Phormio (play by Terence)

    Terence: …the plots of Hecyra and Phormio derives from the Greek models of those plays by Apollodorus of Carystus of the 3rd century bc. Nevertheless, in some important particulars he reveals himself as something more than a translator. First, he shows both originality and skill in the incorporation of material from…

  • Phormion (Greek admiral)

    Phormion, brilliant Athenian admiral who won several engagements before and during the Peloponnesian War. Phormion was one of the generals leading reinforcements to the Athenian siege of Samos in 440. He assisted the Acarnanians and Amphilochians against Ambracia, which resulted in an alliance with

  • phormium (plant and fibre)

    Phormium, (species Phormium tenax), a plant of the day lily family, Hemerocallidaceae, and its fibre, belonging to the leaf fibre group. The plant is native to New Zealand, where the fibre, sometimes called New Zealand “hemp,” or “flax,” has been used since ancient times for cordage, fabrics, and

  • Phormium tenax (plant and fibre)

    Phormium, (species Phormium tenax), a plant of the day lily family, Hemerocallidaceae, and its fibre, belonging to the leaf fibre group. The plant is native to New Zealand, where the fibre, sometimes called New Zealand “hemp,” or “flax,” has been used since ancient times for cordage, fabrics, and

  • phoronid (marine invertebrate)

    Horseshoe worm, phylum name Phoronida, a small group (about 12 species) of wormlike marine invertebrates that live in tubes secreted by special glands. These protective tubes become encrusted with shells or are buried in sand. Horseshoe worms, or phoronids, either are solitary or occur in groups

  • Phoronida (marine invertebrate)

    Horseshoe worm, phylum name Phoronida, a small group (about 12 species) of wormlike marine invertebrates that live in tubes secreted by special glands. These protective tubes become encrusted with shells or are buried in sand. Horseshoe worms, or phoronids, either are solitary or occur in groups

  • Phororhacos (fossil bird genus)

    Diatryma: …characterized by the unrelated genus Phorusrhacos, common during the Miocene Epoch (between 7,000,000 and 26,000,000 years ago). It was about 1 12 metres (5 feet) in height and also had weakly developed wings, strong legs, a large head, and a powerful beak.

  • Phorusrhacos (fossil bird genus)

    Diatryma: …characterized by the unrelated genus Phorusrhacos, common during the Miocene Epoch (between 7,000,000 and 26,000,000 years ago). It was about 1 12 metres (5 feet) in height and also had weakly developed wings, strong legs, a large head, and a powerful beak.

  • Phos hilarion (hymn)

    hymn: …the Greek “Phos hilarion” (“Go, Gladsome Light,” translated by the 19th-century American poet Henry Wadsworth Longfellow). Hymnody developed systematically, however, only after the emperor Constantine legalized Christianity (313 ce), and it flourished earliest in Syria, where the practice was possibly taken over from the singing by gnostics and Manichaeans…

  • phosgene (chemical compound)

    Phosgene, a colourless, chemically reactive, highly toxic gas having an odour like that of musty hay, used in making organic chemicals, dyestuffs, polycarbonate resins, and isocyanates for making polyurethane resins. It first came into prominence during World War I, when it was used, either alone

  • phosphagen (chemical compound)

    muscle: Energy stores: …the reactions of compounds called phosphagens. All of these compounds contain phosphorus in a chemical unit called a phosphoryl group, which they transfer to ADP to produce ATP (these compounds are also referred to as high-energy phosphates).

  • phosphatase (enzyme)

    muscle: Initiation of contraction: Phosphatases are enzymes in the muscle cell that cleave the phosphate group from the myosin light chain.

  • phosphatation (chemical reaction)

    sugar: Clarification and decolorization: …syrup is clarified either by phosphatation, in which phosphoric acid and lime are added to form calcium phosphates, which are removed by surface scraping in a flotation clarifier, or by carbonatation, in which carbon dioxide gas and lime form calcium carbonate, which is filtered off. Colour precipitants are added to…

  • phosphate (chemical compound)

    Phosphate, any of numerous chemical compounds related to phosphoric acid (H3PO4). One group of these derivatives is composed of salts containing the phosphate ion (PO43−), the hydrogen phosphate ion (HPO42−), or the dihydrogen phosphate ion (H2PO4−), and positively charged ions such as those of

  • phosphate glass (material science)

    amorphous solid: Properties of oxide glasses: Phosphate glasses (used as optical glasses) based on phosphorus pentoxide (P2O5) are highly resistant to hydrofluoric acid and act as efficient heat absorbers when iron oxide is added. The table of some typical commercial oxide glasses of the types described gives their compositions and physical…

  • phosphate mineral

    Phosphate mineral, any of a group of naturally occurring inorganic salts of phosphoric acid, H3(PO4). More than 200 species of phosphate minerals are recognized, and structurally they all have isolated (PO4) tetrahedral units. Phosphates can be grouped as: (1) primary phosphates that have

  • Phosphate Mining Company of Christmas Island, Ltd. (Australian company)

    Christmas Island: …six years later to the Christmas Island Phosphate Company, Ltd., which was largely owned by the former lessees. In 1900 Christmas Island was incorporated in the British crown colony of the Straits Settlements with its capital at Singapore. During World War II the island was occupied by the Japanese. In…

  • phosphate rock (mineral)

    Phosphorite, rock with a high concentration of phosphates in nodular or compact masses. The phosphates may be derived from a variety of sources, including marine invertebrates that secrete shells of calcium phosphate, and the bones and excrement of vertebrates. The thickest deposits of phosphorite

  • phosphatide (biochemistry)

    Phospholipid, any member of a large class of fatlike, phosphorus-containing substances that play important structural and metabolic roles in living cells. The phospholipids, with the sphingolipids, the glycolipids, and the lipoproteins, are called complex lipids, as distinguished from the simple

  • phosphatidic acid (chemical compound)

    metabolism: Formation of lipids: …(neutral fat) is formed from phosphatidic acid in a reaction catalyzed by a phosphatase that results in loss of the phosphate group (reaction [84]); the diglyceride thus formed can then accept a third molecule of fatty acyl coenzyme A (represented as R″C∥OS―CoA in [84a]).

  • phosphatidyl choline (biochemistry)

    Lecithin, any of a group of phospholipids (phosphoglycerides) that are important in cell structure and metabolism. Lecithins are composed of phosphoric acid, cholines, esters of glycerol, and two fatty acids; the chain length, position, and degree of unsaturation of these fatty acids vary, and

  • phosphatidylinositol (chemical compound)

    metabolism: Formation of lipids: …form CMP and, respectively, phosphatidylserine, phosphatidylinositol (in [85b]), or 3-phosphatidyl-glycerol 1′-phosphate (PGP; in [85c]). These reactions differ from those of polysaccharide biosynthesis ([79], [82]) in that phosphate is retained in the phospholipid, and the nucleotide product (CMP) is therefore a nucleoside monophosphate rather than the diphosphate. These compounds can react…

  • phosphatidylinositol system (biochemistry)

    lipid: Intracellular second messengers: …intracellular second-messenger signaling system, the phosphatidylinositol system, employs two second-messenger lipids, both of which are derived from phosphatidylinositol. One is diacylglycerol (diglyceride), the other is triphosphoinositol. In this system a membrane receptor acts upon an enzyme, phospholipase C, located on the inner surface of the cell membrane. Activation of this…

  • phosphatidylserine (chemical compound)

    metabolism: Formation of lipids: …1-phosphate—to form CMP and, respectively, phosphatidylserine, phosphatidylinositol (in [85b]), or 3-phosphatidyl-glycerol 1′-phosphate (PGP; in [85c]). These reactions differ from those of polysaccharide biosynthesis ([79], [82]) in that phosphate is retained in the phospholipid, and the nucleotide product (CMP) is therefore a nucleoside monophosphate rather than the diphosphate. These compounds can…

  • Phosphatocopida (fossil crustacean order)

    crustacean: Annotated classification: †Order Phosphatocopida Cambrian; remarkable fossils with up to 9 pairs of well-preserved appendages. †Order Leperditicopida Cambrian to Devonian. †Order Beyrichicopida Silurian to Carboniferous. Subclass

  • phosphene (visual impression)

    radiation: Brain and sensory organs: 01 Gy) can produce phosphene, a light sensation on the dark-adapted retina. American astronauts on the first spacecraft that landed on the Moon (Apollo 11, July 20, 1969) observed irregular light flashes and streaks during their flight, which probably resulted from single heavy cosmic-ray particles striking the retina. In…

  • phosphide (chemical compound)

    Phosphide, any of a class of chemical compounds in which phosphorus is combined with a metal. The phosphide ion is P3−, and phosphides of almost every metal in the periodic table are known. They exhibit a wide variety of chemical and physical properties. Although there are a number of ways to

  • phosphine (chemical compound)

    Phosphine (PH3), a colourless, flammable, extremely toxic gas with a disagreeable garliclike odour. Phosphine is formed by the action of a strong base or hot water on white phosphorus or by the reaction of water with calcium phosphide (Ca3P2). Phosphine is structurally similar to ammonia (NH3), but

  • phosphite (chemical compound)

    oxyacid: Phosphorous acid and phosphite salts: Pure phosphorous acid, H3PO3, is best prepared by hydrolysis of phosphorus trichloride, PCl3. PCl3 + 3H2O → H3PO3 + 3HCl The resulting solution is heated to drive off the HCl, and the remaining water is evaporated until colourless crystalline H3PO3

  • phosphocreatine (chemical compound)

    muscle: Energy stores: …the reactions of compounds called phosphagens. All of these compounds contain phosphorus in a chemical unit called a phosphoryl group, which they transfer to ADP to produce ATP (these compounds are also referred to as high-energy phosphates).

  • phosphodiesterase (enzyme)

    asthma: Treatment and management of asthma: Agents that block enzymes called phosphodiesterases, which are involved in mediating airway constriction and inflammation, are in clinical trials. These drugs are designed to be long-lasting—administered once per day via inhalation—and are expected to be safer than traditional medications, which may cause cardiovascular damage. A prolonged asthma attack that does…

  • phosphodiesterase-5 inhibitor (category of drugs)

    PDE-5 inhibitor, category of drugs that relieve erectile dysfunction (impotence) in men. Two common commercially produced PDE-5 inhibitors are sildenafil (sold as Viagra) and vardenafil (Levitra). PDE-5 inhibitors work by blocking, or inhibiting, the action of phosphodiesterase-5 (PDE-5), an enzyme

  • phosphoenolpyruvate (chemical compound)

    metabolism: The formation of ATP: … reacts with 2-phosphoglycerate to form phosphoenolpyruvate (PEP), water being lost from 2-phosphoglycerate in the process. Phosphoenolpyruvate acts as the second source of ATP in glycolysis. The transfer of the phosphate group from PEP to ADP, catalyzed by pyruvate kinase [10], is also highly exergonic and is thus virtually irreversible under…

  • phosphoenolpyruvate carboxykinase (enzyme)

    metabolism: Growth of microorganisms on TCA cycle intermediates: …this step is catalyzed by phosphoenolpyruvate (PEP) carboxykinase ([54]). Oxaloacetate is decarboxylated (i.e., carbon dioxide is removed) during this energy-requiring reaction. The energy may be supplied by ATP or a similar substance (e.g., GTP) that can readily be derived from it via a reaction of the type shown in [43a].…

  • phosphofructokinase (enzyme)

    Phosphofructokinase, enzyme that is important in regulating the process of fermentation, by which one molecule of the simple sugar glucose is broken down to two molecules of pyruvic acid. The enzyme, one of a class called transferases, catalyzes one of several specific reactions involved in this

  • phosphoglucoisomerase (enzyme)

    metabolism: Glycolysis: …fructose 6-phosphate is catalyzed by phosphoglucoisomerase [2]. In the reaction, a secondary alcohol group (―C∣HOH) at the second carbon atom is oxidized to a keto-group (i.e., ―C∣=O), and the aldehyde group (―CHO) at the first carbon atom is reduced to a primary alcohol group (―CH2OH). Reaction [2] is readily reversible,…

  • phosphoglucomutase (enzyme)

    metabolism: Release of glucose from glycogen: …converted to glucose 6-phosphate by phosphoglucomutase [7, 8], which catalyzes a reaction very similar to that effected in step [8] of glycolysis. Glucose 6-phosphate can then undergo further catabolism via glycolysis [2, 3, 4, 5, 6, 7, 8, 9, 10] or via either of the routes involving formation of 6-phosphogluconate…

  • phosphogluconate oxidative glycolytic pathway (chemical reaction)

    metabolism: The phosphogluconate pathway: Many cells possess, in addition to all or part of the glycolytic pathway that comprises reactions [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11], other pathways of glucose catabolism that involve, as the first unique step, the oxidation of…

  • phosphogluconate pathway (chemical reaction)

    metabolism: The phosphogluconate pathway: Many cells possess, in addition to all or part of the glycolytic pathway that comprises reactions [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11], other pathways of glucose catabolism that involve, as the first unique step, the oxidation of…

  • phosphoglycerate kinase (enzyme)

    metabolism: The formation of ATP: …in a reaction catalyzed by phosphoglycerate kinase, with the result that one of the two phosphoryl groups is transferred to ADP to form ATP and 3-phosphoglycerate. This reaction [7] is highly exergonic (i.e., it proceeds with a loss of free energy); as a result, the oxidation of glyceraldehyde 3-phosphate, step…

  • phosphoglyceride (biochemistry)

    Phospholipid, any member of a large class of fatlike, phosphorus-containing substances that play important structural and metabolic roles in living cells. The phospholipids, with the sphingolipids, the glycolipids, and the lipoproteins, are called complex lipids, as distinguished from the simple

  • phosphoglyceromutase (enzyme)

    metabolism: The formation of ATP: …in a reaction catalyzed by phosphoglyceromutase [8]. During step [9] the enzyme enolase reacts with 2-phosphoglycerate to form phosphoenolpyruvate (PEP), water being lost from 2-phosphoglycerate in the process. Phosphoenolpyruvate acts as the second source of ATP in glycolysis. The transfer of the phosphate group from PEP to ADP, catalyzed by…

  • phosphoglycolate (chemical compound)

    peroxisome: …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.

  • phosphoglycollate (chemical compound)

    peroxisome: …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.

  • phospholipase A2 (enzyme)

    glucocorticoid: …indirectly inhibit the activity of phospholipase A2, an enzyme that plays an essential role in the synthesis of prostaglandins and leukotrienes; its inhibition by lipocortin-1 underlies part of the anti-inflammatory effects of glucocorticoids. Glucocorticoids also reduce the synthesis of some proteins that directly mediate the inflammatory response.

  • phospholipid (biochemistry)

    Phospholipid, any member of a large class of fatlike, phosphorus-containing substances that play important structural and metabolic roles in living cells. The phospholipids, with the sphingolipids, the glycolipids, and the lipoproteins, are called complex lipids, as distinguished from the simple

  • phosphomannomutase 2 (enzyme)

    metabolic disease: Congenital disorders of glycosylation: …defect in a mannose-processing enzyme, phosphomannomutase 2, causes the most common form of CDG (type I). Other enzymatic defects have been identified, but the biochemical bases of some CDG subtypes have not yet been determined. The classic form of CDG (type Ia) is characterized by low muscle tone in infancy,…

  • phosphomannose isomerase deficiency (pathology)

    metabolic disease: Congenital disorders of glycosylation: …rare type Ib disease (phosphomannose isomerase deficiency), in which oral administration of mannose may reverse symptoms in some cases.

  • phosphor (luminescent material)

    Phosphor, solid material that emits light, or luminesces, when exposed to radiation such as ultraviolet light or an electron beam. Hundreds of thousands of phosphors have been synthesized, each one having its own characteristic colour of emission and period of time during which light is emitted

  • phosphor bronze (metallurgy)

    Phosphor bronze, alloy of copper and tin that contains a trace of phosphorus. See

  • phosphorescence (physics)

    Phosphorescence, emission of light from a substance exposed to radiation and persisting as an afterglow after the exciting radiation has been removed. Unlike fluorescence, in which the absorbed light is spontaneously emitted about 10-8 second after excitation, phosphorescence requires additional

  • Phosphoria Formation (geological feature, United States)

    phosphorite: …the United States include the Phosphoria Formation in Idaho and the Monterey Formation in California. Major deposits also occur in the Sechura Desert in Peru. Alteration of phosphorites tends to leach carbonates and sulfides and increase the percentage of phosphorus pentoxide. The Phosphoria Formation, for example, contains about 34 percent…

  • phosphoric acid (chemical compound)

    Phosphoric acid, (H3PO4), the most important oxygen acid of phosphorus, used to make phosphate salts for fertilizers. It is also used in dental cements, in the preparation of albumin derivatives, and in the sugar and textile industries. It serves as an acidic, fruitlike flavouring in food products.

  • phosphoric acid fuel cell (device)

    fuel cell: Phosphoric acid fuel cells: Such cells have an orthophosphoric acid electrolyte that allows operation up to about 200 °C (400 °F). They can use a hydrogen fuel contaminated with carbon dioxide and an oxidizer of air or oxygen. The electrodes consist of catalyzed carbon and…

  • phosphoric anhydride (chemical compound)

    nitrile: …formed by heating amides with phosphorous pentoxide. They can be reduced to primary amines through the action of lithium aluminum hydride or hydrolyzed to carboxylic acids in the presence of either an acid or a base.

  • phosphorimeter (instrument)

    chemical analysis: Luminescence: …employed to measure phosphorescence are phosphorimeters. Phosphorimeters differ from fluorometers in that they monitor luminescent intensity while the exciting radiation is not striking the cell.

  • phosphorite (mineral)

    Phosphorite, rock with a high concentration of phosphates in nodular or compact masses. The phosphates may be derived from a variety of sources, including marine invertebrates that secrete shells of calcium phosphate, and the bones and excrement of vertebrates. The thickest deposits of phosphorite

  • phosphorolysis (biochemistry)

    metabolism: Formation of coenzyme A, carbon dioxide, and reducing equivalent: …succinyl coenzyme A undergoes a phosphorolysis reaction—i.e., transfer of the succinyl moiety from coenzyme A to inorganic phosphate. The succinyl phosphate thus formed is not released from the enzyme surface; an unstable, high-energy compound called an acid anhydride, it transfers a high-energy phosphate to ADP, directly or via guanosine diphosphate…

  • phosphorous acid (chemical compound)

    Phosphorous acid (H3PO3), one of several oxygen acids of phosphorus, used as reducing agent in chemical analysis. It is a colourless or yellowish crystalline substance (melting point about 73° C, or 163° F) with a garliclike taste. An unstable compound that readily absorbs moisture, it is converted

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