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  • Proteidae (amphibian)

    Caudata: Annotated classification: Family Proteidae (olms and mud puppies) The olm is blind, has little pigment, has an elongated body, and is cave-dwelling; mud puppies live in lakes and streams, have eyes, and are normally pigmented; elongate bodies, length to 45 cm; limbs with 3 (olm) or 4 fingers,…

  • protein (biochemistry)

    Protein, highly complex substance that is present in all living organisms. Proteins are of great nutritional value and are directly involved in the chemical processes essential for life. The importance of proteins was recognized by chemists in the early 19th century, including Swedish chemist Jöns

  • protein C (biochemistry)

    bleeding and blood clotting: Inhibition of clotting: Protein C, a vitamin K-dependent protein, is a zymogen that requires vitamin K for its activation by thrombin complexed to thrombomodulin, a protein on the endothelial cell membrane. Activated protein C is capable of inactivating the active cofactor forms of factors VIII and V. Its…

  • protein capsid (virus structure)

    virus: Definition: …forms a shell (called a capsid) around the nucleic acid. Certain viruses also have other proteins internal to the capsid; some of these proteins act as enzymes, often during the synthesis of viral nucleic acids. Viroids (meaning “viruslike”) are disease-causing organisms that contain only nucleic acid and have no structural…

  • protein cofactor (biochemistry)

    bleeding and blood clotting: Biochemical basis of activation: Protein cofactors also play an important role in blood coagulation. Two protein cofactors, factor V and factor VIII, are large proteins that probably regulate blood coagulation. These proteins circulate in the blood as inactive cofactors. By the process of limited proteolysis, in which several cuts…

  • protein concentrate (dietary supplement)

    Protein concentrate, a human or animal dietary supplement that has a very high protein content and is extracted or prepared from vegetable or animal matter. The most common of such substances are leaf protein concentrate (LPC) and fish protein concentrate (FPC). LPC is prepared by grinding young

  • protein degradation (chemistry)

    Aaron J. Ciechanover: …Rose also demonstrated that ubiquitin-mediated protein degradation helps control a number of other critical biochemical processes, including cell division, the repair of defects in DNA, and gene transcription, the process in which genes use their coded instructions to manufacture a protein. Diseases such as cystic fibrosis result when the protein-degradation…

  • protein fibre (textile)

    Azlon, synthetic textile fibre composed of protein material derived from natural sources. It is produced, like other synthetic fibres, by converting the raw material to a solution that is extruded through the holes of a device called a spinneret and then stretched to improve the alignment of the

  • protein hormone (biochemistry)

    protein: Protein hormones: Some hormones that are products of endocrine glands are proteins or peptides, others are steroids. (The origin of hormones, their physiological role, and their mode of action are dealt with in the article hormone.) None of the hormones has any enzymatic activity. Each…

  • protein malnutrition (pathology)

    Kwashiorkor, condition caused by severe protein deficiency. Kwashiorkor is most often encountered in developing countries in which the diet is high in starch and low in proteins. It is common in young children weaned to a diet consisting chiefly of cereal grains, cassava, plantain, and sweet potato

  • protein phosphorylation (chemical reaction)

    Paul Greengard: …involves a chemical reaction called protein phosphorylation; in that reaction a phosphate molecule is linked to protein, changing the protein’s function. Greengard worked out the signal transduction pathway that begins with dopamine. When dopamine attaches to receptors in a neuron’s outer membrane, it causes a rise in a second messenger,…

  • protein S (biochemistry)

    bleeding and blood clotting: Inhibition of clotting: …is enhanced when bound to protein S, a vitamin K-dependent protein that is attached to cell membranes (platelet or possibly endothelial cells). A deficiency in the level of protein C or protein S is associated with an excessive tendency to form clots.

  • protein synthesis (genetics)

    Translation, the synthesis of protein from RNA. Hereditary information is contained in the nucleotide sequence of DNA in a code. The coded information from DNA is copied faithfully during transcription into a form of RNA known as messenger RNA (mRNA), which is then translated into chains of amino

  • protein-base fibre (raw material)

    natural fibre: Classification and properties: The animal, or protein-base, fibres include wool, mohair, and silk. An important fibre in the mineral class is asbestos.

  • protein-bound iodine test (medicine)

    Protein-bound iodine test, laboratory test that indirectly assesses thyroid function by measuring the concentration of iodine bound to proteins circulating in the bloodstream. Thyroid hormones are formed by the addition of iodine to the amino acid tyrosine and are normally transported in the

  • protein-calorie malnutrition (pathology)

    nutritional disease: Protein-energy malnutrition: Chronic undernutrition manifests primarily as protein-energy malnutrition (PEM), which is the most common form of malnutrition worldwide. Also known as protein-calorie malnutrition, PEM is a continuum in which people—all too often children—consume too little protein, energy, or both. At one end of the continuum…

  • protein-energy malnutrition (pathology)

    nutritional disease: Protein-energy malnutrition: Chronic undernutrition manifests primarily as protein-energy malnutrition (PEM), which is the most common form of malnutrition worldwide. Also known as protein-calorie malnutrition, PEM is a continuum in which people—all too often children—consume too little protein, energy, or both. At one end of the continuum…

  • protein-splitting enzyme (enzyme)

    Proteolytic enzyme, any of a group of enzymes that break the long chainlike molecules of proteins into shorter fragments (peptides) and eventually into their components, amino acids. Proteolytic enzymes are present in bacteria, archaea, certain types of algae, some viruses, and plants; they are

  • proteinase (enzyme)

    Proteolytic enzyme, any of a group of enzymes that break the long chainlike molecules of proteins into shorter fragments (peptides) and eventually into their components, amino acids. Proteolytic enzymes are present in bacteria, archaea, certain types of algae, some viruses, and plants; they are

  • proteinosis, alveolar (pathology)

    Pulmonary alveolar proteinosis, respiratory disorder caused by the filling of large groups of alveoli with excessive amounts of surfactant, a complex mixture of protein and lipid (fat) molecules. The alveoli are air sacs, minute structures in the lungs in which the exchange of respiratory gases

  • proteinuria (pathology)

    Proteinuria, presence of protein in the urine, usually as albumin. Protein is not normally found in the urine of healthy individuals. When detected, proteinuria may be indicative of illness or underlying disease. However, while proteinuria is a sign of many different conditions and diseases, it

  • Proteles cristatus (mammal)

    Aardwolf, (Proteles cristatus), insectivorous carnivore that resembles a small striped hyena. The shy, mainly nocturnal aardwolf lives on the arid plains of Africa. There are two geographically separate populations, one centred in South Africa and the other in East Africa. The aardwolf, whose name

  • Protemnodon (marsupial)

    wallaby: …species of brush wallabies (genus Macropus, subgenus Protemnodon) are built like the big kangaroos but differ somewhat in dentition. Their head and body length is 45 to 105 cm (18 to 41 inches), and the tail is 33 to 75 cm long. A common species is the red-necked wallaby (M.…

  • Protentombrya walkeri (collembolan species)

    apterygote: Evolution and paleontology: …(Protentomobryidae) contains a species (Protentomobrya walkeri) of the Cretaceous Period (approximately 100 million years ago) of Canada. One of the oldest fossil collembolan species, Rhyniella praecursor (family Neanuridae), is found in the Rhynie chert of the Early Devonian (approximately 419 million to 393 million years ago) sandstone of Scotland.…

  • Protentomidae (arthropod family)
  • Proteocephalidea (tapeworm order)

    flatworm: Annotated classification: Order Proteocephalidea Scolex with 4 suckers, sometimes a 5th terminal one; vitellaria located in lateral margins; genital pores lateral; mainly parasites of cold-blooded vertebrates; about 185 species. Order Diphyllidea Two bothridia, each sometimes bisected by a median longitudinal ridge; large rostellum (cone-shaped or cylindrical projection) armed…

  • proteoglycan (biochemistry)

    human skin: The dermis: …collagen, with materials known as glycosaminoglycans, which are capable of holding a large amount of water, thus maintaining the turgidity of the skin. A network of extendable elastic fibres keeps the skin taut and restores it after it has been stretched.

  • proteoid (plant)

    scrubland: Biota: …shrubs are heathers (Erica) and proteoids, especially Leucadendron and Protea. The flowers of this extraordinarily diverse flora are pollinated by both insects—but few butterflies—and nectar-eating birds such as sunbirds (Nectarina) and the Cape Sugarbird (Promerops cafer)—animals with which they have coevolved (see community ecology: The coevolutionary process). Seed dispersal by…

  • proteolipid (chemistry)

    protein: Lipoproteins and proteolipids: The bond between the protein and the lipid portion of lipoproteins and proteolipids is a noncovalent one. It is thought that some of the lipid is enclosed in a meshlike arrangement of peptide chains and becomes accessible for reaction only after the unfolding of…

  • proteolysis (chemistry)

    Proteolysis, Process in which a protein is broken down partially, into peptides, or completely, into amino acids, by proteolytic enzymes, present in bacteria and in plants but most abundant in animals. Proteins in food are attacked in the stomach by pepsin and in the small intestine mainly by

  • proteolytic enzyme (enzyme)

    Proteolytic enzyme, any of a group of enzymes that break the long chainlike molecules of proteins into shorter fragments (peptides) and eventually into their components, amino acids. Proteolytic enzymes are present in bacteria, archaea, certain types of algae, some viruses, and plants; they are

  • proteomics (biochemistry)

    bioinformatics: The data of bioinformatics: …of RNA synthesis from DNA; proteomics, the distribution of proteins in cells; interactomics, the patterns of protein-protein and protein–nucleic acid interactions; and metabolomics, the nature and traffic patterns of transformations of small molecules by the biochemical pathways active in cells. In each case there is interest in obtaining comprehensive, accurate…

  • proteomyxid (microorganism)

    Proteomyxid, (subclass Proteomyxidia), any of various microorganisms (class Actinopodea), most of which are parasites in freshwater and saltwater algae or in other plants. Their pseudopodia (cytoplasmic extensions) often fuse. Proteomyxida that have radiating pseudopodia (e.g., Vampyrella) resemble

  • Proteomyxidia (microorganism)

    Proteomyxid, (subclass Proteomyxidia), any of various microorganisms (class Actinopodea), most of which are parasites in freshwater and saltwater algae or in other plants. Their pseudopodia (cytoplasmic extensions) often fuse. Proteomyxida that have radiating pseudopodia (e.g., Vampyrella) resemble

  • Proteopithecus (primate genus)

    primate: Oligocene: …described from Fayum, including Catopithecus, Proteopithecus, Apidium, Qatrania, Propliopithecus, Oligopithecus, Parapithecus, and Aegyptopithecus. The first two of these, together with some other primates of uncertain affinities, are from the Sagha Formation, which, technically, is latest Eocene in age, but the deposits are continuous. Aegyptopithecus went on to give

  • Proterocheris (fossil turtle genus)

    turtle: Origin and evolution: Proterocheris is another ancient fossil turtle that lived at the same time as Proganochelys. Proterocheris has many features that suggest that it is a side-necked turtle. If this is true, the two major taxonomic groups of living turtles, suborders Pleurodira (side-necked turtles) and Cryptodira (hidden…

  • proterothere (fossil mammal)

    litoptern: One line of litopterns, the proterotheres, strongly resembled horses. Their limbs were modified for running and also had special features for locking their knees, allowing them to stand for long periods of time. The proterothere skull was long and low and contained cheek teeth resembling those of deer. Proterotheres became…

  • Proterozoic Eon (geochronology)

    Proterozoic Eon, the younger of the two divisions of Precambrian time, the older being the Archean Eon. The Proterozoic Eon extended from 2.5 billion to 541 million years ago and is often divided into the Paleoproterozoic (2.5 billion to 1.6 billion years ago), the Mesoproterozoic (1.6 billion to 1

  • Proterozoic eonothem (stratigraphy)

    Precambrian: Proterozoic plate movements: During the early Proterozoic, large amounts of quartzite, carbonate, and shale were deposited on the shelves and margins of many continental blocks. This would be consistent with the breakup of a supercontinent into several smaller continents with long continental margins (combined areas…

  • Protesilaus (Greek mythology)

    Protesilaus, Greek mythological hero in the Trojan War, leader of the force from Phylace and other Thessalian cities west of the Pegasaean Gulf. Though aware that an oracle had foretold death for the first of the invading Greeks to land at Troy, he was the first ashore and the first to fall. His

  • Protesilaus (work by Rotelande)

    romance: The setting: …the Anglo-Norman Hue de Rotelande’s Protesilaus, in which the characters have Greek names; the action takes place in Burgundy, Crete, Calabria, and Apulia; and Theseus is described as “king of Denmark.” This lavish use of exotic personal and geographical names and a certain irresponsibility about settings was still to be…

  • protest movement (society)

    anarchism: Anarchism in Spain: …Francisco Ferrer led to worldwide protests and the resignation of the conservative government in Madrid. These events also resulted in a congress of Spanish trade unionists at Sevilla in 1910, which founded the National Confederation of Labour (Confederación Nacional del Trabajo; CNT).

  • Protestant Ascendancy (Irish history)

    Ireland: The Restoration period and the Jacobite war: …this foundation was established the Protestant Ascendancy.

  • Protestant Association (British organization)

    United Kingdom: Domestic responses to the American Revolution: …Relief Act of 1778, the Protestant Association, started in Scotland under the leadership of an unstable individual called Lord George Gordon. The movement reached London and exploded there in riots that lasted for eight days. More than 300 people were killed, and more damage was done to property than would…

  • Protestant Church Bible (biblical translation)

    biblical literature: Hungarian versions: …Vizsoly in 1590, became the Protestant church Bible.

  • Protestant Church in the Netherlands (Dutch Protestant church)

    Protestant Church in the Netherlands, united Christian church, largest Protestant church in the Netherlands, formed in the merger of three Dutch churches. In May 2004, after nearly 20 years of negotiations, the Reformed Churches in the Netherlands (Nederlands Gereformeerde Kerken; then the second

  • Protestant Episcopal Church (autonomous church, United States)

    Episcopal Church in the United States of America (ECUSA), autonomous church in the United States. Part of the Anglican Communion, it was formally organized in Philadelphia in 1789 as the successor to the Church of England in the American colonies. In points of doctrine, worship, and ministerial

  • Protestant ethic (sociology)

    Protestant ethic, in sociological theory, the value attached to hard work, thrift, and efficiency in one’s worldly calling, which, especially in the Calvinist view, were deemed signs of an individual’s election, or eternal salvation. German sociologist Max Weber, in The Protestant Ethic and the

  • Protestant Ethic and the Spirit of Capitalism, The (work by Weber)

    Max Weber: Later works: …der Geist des Kapitalismus (1904–05; The Protestant Ethic and the Spirit of Capitalism), Weber’s best known and most controversial work, illustrates the general trend of his thinking. Weber began by noting the statistical correlation in Germany between interest and success in capitalist ventures on the one hand and Protestant background…

  • Protestant League (French history)

    Michel de Montaigne: Life: …Catholic majority and the important Protestant League representation in Bordeaux. Toward the end of his term the plague broke out in Bordeaux, soon raging out of control and killing one-third of the population.

  • Protestant Orthodoxy (religion)

    Protestant Orthodoxy, phase of orthodoxy that characterized both Lutheran and Reformed theology after the 16th-century Reformation. Protestant Orthodoxy understood Christianity as a system of doctrines, and thus its emphasis was on “right doctrine.” In Lutheranism the period of orthodoxy began

  • Protestant principle (theology)

    Paul Tillich: Development of his philosophy: …which he called the “Protestant principle,” could be given a far wider scope than previously had been thought. Not limited to the classical religious question of how sinful man can be acceptable to a holy God, it could be understood to encompass man’s intellectual life as well, and thus…

  • Protestant Reformation (Christianity)

    Reformation, the religious revolution that took place in the Western church in the 16th century. Its greatest leaders undoubtedly were Martin Luther and John Calvin. Having far-reaching political, economic, and social effects, the Reformation became the basis for the founding of Protestantism, one

  • Protestant Scholasticism (religion)

    Protestant Orthodoxy, phase of orthodoxy that characterized both Lutheran and Reformed theology after the 16th-century Reformation. Protestant Orthodoxy understood Christianity as a system of doctrines, and thus its emphasis was on “right doctrine.” In Lutheranism the period of orthodoxy began

  • Protestant Union (German military alliance)

    Protestant Union, military alliance (1608–21) among the Protestant states of Germany for mutual protection against the growing power of the Roman Catholic states of Counter-Reformation Europe. In February 1608, at the Diet (Reichstag) of the Holy Roman Empire, the Catholic princes introduced a

  • Protestantische Union (German military alliance)

    Protestant Union, military alliance (1608–21) among the Protestant states of Germany for mutual protection against the growing power of the Roman Catholic states of Counter-Reformation Europe. In February 1608, at the Diet (Reichstag) of the Holy Roman Empire, the Catholic princes introduced a

  • Protestantism (Christianity)

    Protestantism, movement that began in northern Europe in the early 16th century as a reaction to medieval Roman Catholic doctrines and practices. Along with Roman Catholicism and Eastern Orthodoxy, Protestantism became one of three major forces in Christianity. After a series of European religious

  • Protestantism and Catholicism Compared in Their Effects on the Civilization of Europe (work by Balmes)

    Jaime Luciano Balmes: …is best known for his El protestantismo comparado con el catolicismo en sus relaciones con la civilización europea (1842–44; Protestantism and Catholicism Compared in Their Effect on the Civilization of Europe), a defense of Roman Catholicism against the accusation of being unsympathetic toward the spirit of progress. His philosophical works…

  • protestantismo comparado con el catolicismo en sus relaciones con la civilización europea, El (work by Balmes)

    Jaime Luciano Balmes: …is best known for his El protestantismo comparado con el catolicismo en sus relaciones con la civilización europea (1842–44; Protestantism and Catholicism Compared in Their Effect on the Civilization of Europe), a defense of Roman Catholicism against the accusation of being unsympathetic toward the spirit of progress. His philosophical works…

  • Protestantse Kerk in Nederland (Dutch Protestant church)

    Protestant Church in the Netherlands, united Christian church, largest Protestant church in the Netherlands, formed in the merger of three Dutch churches. In May 2004, after nearly 20 years of negotiations, the Reformed Churches in the Netherlands (Nederlands Gereformeerde Kerken; then the second

  • Protestation of 1621 (English history)

    United Kingdom: Factions and favourites: …of the Commons prepared the Protestation of 1621, exculpating their conduct and setting forth a statement of the liberties of the house. James sent for the Commons journal and personally ripped the protestation from it. He reiterated his claim that royal marriages and foreign policy were beyond the ken of…

  • Proteus (Greek mythology)

    Proteus, in Greek mythology, the prophetic old man of the sea and shepherd of the sea’s flocks (e.g., seals). He was subject to the sea god Poseidon, and his dwelling place was either the island of Pharos, near the mouth of the Nile River, or the island of Carpathus, between Crete and Rhodes.

  • Proteus (astronomy)

    Neptune: Moons: …of its largest known sibling, Proteus, discovered by Voyager 2 in 1989. Triton is the only large moon of the solar system that travels around its planet in retrograde fashion. Moreover, whereas the orbits of the largest moons in the solar system are inclined less than about 5° to their…

  • Proteus (Italian painter)

    Luca Giordano, the most celebrated and prolific Neapolitan painter of the late 17th century. His nickname Luca Fa Presto (“Luca, Work Quickly”) is said to derive from his painter-copyist father’s admonitions, which were certainly heeded. His other nickname, Proteus, was acquired as a result of his

  • Proteus (amphibian genus)

    Caudata: Annotated classification: …to present; 2 genera (Proteus, native to the northern Balkan Peninsula, and Necturus, of eastern North America) and 6 species. Family Rhyacotritonidae (torrent salamanders) Small dwellers of streams, springs, and seeps; length to 9 cm; 4 fingers and 5 toes; no gills in adults; no fossil record; northwestern United…

  • Proteus (fictional character)

    The Two Gentlemen of Verona: …by chiding his closest friend, Proteus (the other gentleman), for remaining idly at home with his beloved Julia rather than venturing to Milan with him. Shortly thereafter Proteus’s plans change, because of his father’s insistence, and he too heads for Milan after proclaiming his undying love and fidelity to Julia.

  • Proteus anguinus (salamander)

    Olm, (Proteus anguinus), blind salamander belonging to the family Proteidae (order Caudata). It lives in the subterranean streams in karst areas of the Adriatic coast from northeastern Italy southward into Montenegro. As an aquatic cave dweller, the olm has lost its skin pigmentation, and its

  • Proteus syndrome (disease)

    Joseph Merrick: …extremely rare disease known as Proteus syndrome.

  • Protevangelium of James (pseudepigraphal work)

    Protevangelium of James, pseudepigraphal (noncanonical and unauthentic) work written about the mid-2nd century ad to enhance the role of Mary, the mother of Jesus, in Christian tradition. The story of Mary’s childhood as given in the Protevangelium has no parallel in the New Testament, and

  • prothallium (plant anatomy)

    Prothallium, the small, green, heart-shaped structure (gametophyte) of a fern that produces both male and female sex cells (gametes). The prothallium forms from a spore. After fertilization, a young sporophyte plant develops; it consists of a primary root, primary leaf, the rudiment of a new stem,

  • prothesis (architecture)

    sacristy: …apse, the diaconicon and the prothesis, were used for these purposes.

  • prothodontia (dentistry)

    Prosthodontics, dental specialty concerned with restoration and maintenance of oral function, appearance, and comfort by use of prostheses. The oral prostheses replacing teeth may be removable dentures or partial dentures or permanently fixed tooth prostheses, connected to remaining teeth or i

  • prothoracic gland (insect anatomy)

    dormancy: Diapause in insects: …other endocrine organs, specifically the prothoracic glands. Under the stimulation of the brain hormone, the prothoracic glands secrete a hormone called ecdysone. When stimulation by the brain hormone ceases, ecdysone is no longer secreted, and, in its absence, all insect growth and metamorphosis are halted. Thus, provision is made for…

  • prothoracotropin (biochemistry)

    Thoracotropic hormone, neurohormone secreted in arthropods. After being released by neurosecretory cells of the brain, the thoracotropic hormone is carried by the blood to the prothoracic glands, where it stimulates the release of ecdysone in insects or crustecdysone in crustaceans, steroid h

  • prothorax (anatomy)

    lepidopteran: Thorax: The prothorax bears the first pair of legs and a pair of respiratory openings (spiracles). The much larger mesothorax bears the second pair of legs, a second pair of spiracles, and the pair of forewings. The metathorax bears the third pair of legs and the pair…

  • prothrombin (biochemistry)

    Prothrombin, glycoprotein (carbohydrate-protein compound) occurring in blood plasma and an essential component of the blood-clotting mechanism. Prothrombin is transformed into thrombin by a clotting factor known as factor X or prothrombinase; thrombin then acts to transform fibrinogen, also present

  • prothrombin deficiency (pathology)

    Hypoprothrombinemia, disease characterized by a deficiency of the blood-clotting substance prothrombin, resulting in a tendency to prolonged bleeding. Hypoprothrombinemia is usually associated with a lack of vitamin K, which is necessary for the synthesis of prothrombin in the liver cells. In

  • prothrombin time (biochemistry)

    bleeding and blood clotting: The extrinsic pathway of blood coagulation: …simple test known as the prothrombin time. Tissue extract, or tissue thromboplastin, is extracted from animal tissues rich in tissue factor. Plasma, anticoagulated with citrate buffer, is allowed to clot with the simultaneous addition of phospholipid, calcium, and thromboplastin. The duration of time until clot formation, known as the prothrombin…

  • prothrombinase (biochemistry)

    coagulation: …result in the production of factor X. The activation of this factor marks the beginning of the so-called common pathway of coagulation, which results in the formation of a clot.

  • Protić, Stojan (Serbian statesman)

    Stojan Protić, Serbian statesman and editor who was the first prime minister of the Kingdom of Serbs, Croats, and Slovenes (1918–19, 1920), later called Yugoslavia. Having studied history and philology in Belgrade, Protić briefly worked in government service before devoting himself to journalism

  • protist (eukaryote)

    Protist, any member of a group of diverse eukaryotic, predominantly unicellular microscopic organisms. They may share certain morphological and physiological characteristics with animals or plants or both. The term protist typically is used in reference to a eukaryote that is not a true animal,

  • Protista (eukaryote)

    Protist, any member of a group of diverse eukaryotic, predominantly unicellular microscopic organisms. They may share certain morphological and physiological characteristics with animals or plants or both. The term protist typically is used in reference to a eukaryote that is not a true animal,

  • protium (isotope)

    Protium, isotope of hydrogen (q.v.) with atomic weight of approximately 1; its nucleus consists of only one proton. Ordinary hydrogen is made up almost entirely of

  • Protium (plant genus)

    Sapindales: Distribution and abundance: Protium (85 species) occurs mostly in wet lowland areas of tropical America but with a few species in Madagascar and Malaysia. Canarium (75 species) occurs in the forests of the Old World tropics. Bursera (50 species) is found in tropical America, with its centre of…

  • Proto-Afro-Asiatic language

    Afro-Asiatic languages: Origins: …originated is referred to as Proto-Afro-Asiatic. Proto-Afro-Asiatic is of great antiquity; experts tend to place it in the Mesolithic Period at about 15,000–10,000 bce. There is no general consensus over the location of the Urheimat, the original homeland from which began the migrations into the present locations of the speakers.…

  • Proto-Attic style (Greek art)

    Western painting: Orientalizing period (c. 700–625 bc): …the new style is called Proto-Attic and includes, for the first time, scenes referring unambiguously to Greece’s heroic past. The exploits of Heracles, Perseus, and other heroes were painted, often on large vases used as burial containers. The bodies of men and animals were depicted in silhouette, though their heads…

  • Proto-Austronesian language

    Austronesian languages: Major subgroups: …after the initial breakup of Proto-Austronesian itself.

  • Proto-Celtic language

    Celtic languages: Common Celtic: The reconstruction of Common Celtic (or Proto-Celtic)—the parent language that yielded the various tongues of Continental Celtic and Insular Celtic—is of necessity very tentative. Whereas Continental Celtic offers plenty of evidence for phonology (the sound system), its records are too scanty to help…

  • Proto-Chadic language

    Afro-Asiatic languages: Proving genetic relationship: problems of internal comparison: , Proto-Chadic or Proto-Semitic), or a hypothetical common sound of origin. Languages are said to be genetically related when they meet two criteria: they match in phonology, vocabulary, and grammar in such a way that they can be systematically related to a common protolanguage, and the…

  • Proto-Chimú (ancient South American culture)

    Moche, Andean civilization that flourished from the 1st to the 8th century ce on the northern coast of what is now Peru. The name is taken from the great site of Moche, in the river valley of the same name, which appears to have been the capital or chief city of the Moche peoples. Their settlements

  • Proto-Chinese languages

    Chinese languages: …of the Chinese languages into Proto-Sinitic (Proto-Chinese; until 500 bc), Archaic (Old) Chinese (8th to 3rd century bc), Ancient (Middle) Chinese (through ad 907), and Modern Chinese (from c. the 10th century to modern times). The Proto-Sinitic period is the period of the most ancient inscriptions and poetry; most loanwords…

  • Proto-Corinthian style (Greek art)

    Proto-Corinthian style, Greek pottery style that flourished at Corinth during the Oriental period (c. 725–c. 600 bce). Proto-Corinthian pottery, most of which is miniature in size, was the first to be decorated in the black-figure painting technique: figure silhouettes drawn in black and filled in

  • Proto-Dravidian language

    Dravidian languages: Proto-Dravidian Phonology: The Proto-Dravidian sound system has five short vowels (*/i/, */e/, */a/, */o/, */u/) and their five long counterparts (*/ī/, */ē/, */ā/, */ō/, */ū/). The language has 16 consonants. Vowels that are variable are denoted as V and variable consonants as C. In English,…

  • proto-Earth (astronomy)

    Moon: Origin and evolution: In fission theories a fluid proto-Earth began rotating so rapidly that it flung off a mass of material that formed the Moon. Although persuasive, the theory eventually failed when examined in detail; scientists could not find a combination of properties for a spinning proto-Earth that would eject the right kind…

  • Proto-Euphratean (people)

    Sumer: …now are called proto-Euphrateans or Ubaidians, for the village Al-ʿUbayd, where their remains were first discovered. The Ubaidians were the first civilizing force in Sumer, draining the marshes for agriculture, developing trade, and establishing industries, including weaving, leatherwork, metalwork, masonry, and pottery. After the Ubaidian immigration to Mesopotamia, various Semitic…

  • Proto-Geometric style (Greek art)

    Proto-Geometric style, visual art style of ancient Greece that signaled the reawakening of technical proficiency and conscious creative spirit, especially in pottery making. With the collapse of the Minoan-Mycenaean civilization about the 12th century bc, the arts sustained by the palace

  • Proto-Germanic language

    Indo-European languages: Changes in morphology: Proto-Germanic had only six cases, the functions of ablative (place from which) and locative (place in which) being taken over by constructions of preposition plus the dative case. In Modern English these are reduced to two cases in nouns, a general case that does duty…

  • Proto-Hittite language

    Hattian language, non-Indo-European language of ancient Anatolia. The Hattian language appears as hattili ‘in Hattian’ in Hittite cuneiform texts. Called Proto-Hittite by some, Hattian was the language of the linguistic substratum inside the Halys River (now called the Kızıl River) bend and in

  • Proto-Indo-European language

    Indo-European languages: The parent language: Proto-Indo-European: By comparing the recorded Indo-European languages, especially the most ancient ones, much of the parent language from which they are descended can be reconstructed. This reconstructed parent language is sometimes called simply Indo-European, but in this article the term Proto-Indo-European is preferred.

  • Proto-Indus culture (ancient Asian history)

    India: The early prehistoric period: The terms Early Harappan and Harappan (from the site where remains of a major city of the Indus civilization were discovered in 1921) are used primarily in a chronological way but also loosely in a cultural sense, relating respectively to periods or cultures that preceded the appearance…

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