root In botany, the underground anchoring part of a plant. It grows downward in response to gravity, absorbs water and dissolved minerals, and stores reserve food. Primary root systems have a deep sturdy taproot (in gymnosperms and dicots; see cotyledon) plus secondary or lateral smaller roots, and root hairs. Grasses and other monocots produce a shal¬ low diffuse mass of fibrous secondary roots. Additional support (e.g., in corn and orchids) comes from stem offshoots called adventitious, or prop, roots. Fleshy roots that store food may be modified taproots (e.g., carrots, turnips, and beets) or modified adventitious roots (e.g. cassava). Tubers such as the potato are modified, fleshy, underground stems, or rhizomes. Aerial roots arise from the stem and either pass for some distance through the air before reaching the soil or remain hanging in the air. See illustration opposite.
Root, Elihu (b. Feb. 15, 1845, Clinton, N.Y., U.S.—d. Feb. 7. 1937, New York, N.Y.) U.S. lawyer and diplomat. He became a U.S. attorney for the southern district of New York in 1883. He served as secretary of war from 1899 to 1904. After the Spanish-American War, he set up a civil government in Puerto Rico and organized U.S. control of the Philippines. As secretary of state (1905-09) under Theodore Roosevelt, he concluded treaties with Japan and persuaded Latin American states to participate in
the second Hague conference in 1907 (see Hague Conventions). He was awarded the Nobel Prize for Peace in 1912. He served in the U.S. Senate from 1909 to 1915. A supporter of the League of Nations, he helped frame the statute that established the International Court of Justice.
rope Assemblage of fibres, filaments, or wires compacted by twisting or braiding into a long, flexible line. Wire rope is often referred to as cable. The basic requirement for service is that the rope remain firmly compacted and structurally stable, even while being bent, twisted, and pulled. The most important property of a rope is its tensile strength. Because even short fibres can be spun into long flexible yarns, practically any fibre can be made into a rope. Braided ropes deteriorate more slowly than twisted ropes.
Roper River River, Northern Territory, Australia. It flows east to Lim- men Bight on the Gulf of Carpentaria; it is about 325 mi (525 km) long and is navigable for about 90 mi (145 km). It marks the southern limit of the region known as Arnhem Land. North of the river’s mouth is the “Ruined City of Arnhem Land,” a region of sandstone whose weathered shapes suggest ruined buildings.
Rorik See Rurik
rorqual Vror-kwoL Any of five species of baleen whales in the genus Balaenoptera (family Balaenopteridae), namely, the blue, fin, sei, Bryde’s, and minke whales. The term often includes the humpback whale, the only other member of the family.
Rorschach Vror-.shakV Hermann (b. Nov. 8, 1884, Zurich, Switz.—d. April 2, 1922, Herisau) Swiss psychiatrist. The eldest son of an art teacher, he was given the nickname Kleck, meaning “inkblot,” as a schoolboy because of his interest in sketching. After receiving his M.D. from the University of Zurich in 1912, he became a practitioner of psy¬ choanalysis and became vice president of the Swiss Psychoanalytic Soci¬ ety in 1919. He devised the Rorschach test to gauge the perceptions, intelligence, and emotional traits of his patients and used it to gather the data that he summarized in Psychodiagnostics (1921).
Structure of a root. The apical meristem is an area of actively dividing cells that forms all the root's cells. The root cap provides a protective covering that facilitates passage of the root through soil. Cells become specialized for specific functions in the zone of differentiation, or maturation zone. The epidermal layer allows passage of water and dissolved materials into the interior. Cells of the cortex store food and transport water and substances to the endodermis, which regulates their entry into the vascular cylinder, containing the xylem (for transporting water and dissolved minerals to the rest of the plant) and phloem (for transporting nutrients made in the leaves).
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1642 I Rorty ► rose window
Rorty, Richard (McKay) (b. Oct. 4,1931, New York, N.Y., U.S.) U.S. philosopher. After receiving his Ph.D. at Yale University in 1956, he taught at Wellesley College, Princeton University, the University of Vir¬ ginia, and Stanford University. An opponent of epistemological founda- tionalism, Rorty holds that no statement is epistemologically more basic than any other and no statement is ever justified finally or absolutely. He also rejects the idea that sentences or beliefs are true or false in any inter¬ esting sense other than being useful or successful within a broad social practice (see pragmatism). Because there is no such thing as certainty or absolute truth, according to Rorty, it is not the purpose of philosophy to pursue such things; its role instead should be to conduct a “conversation” between contrasting but equally valid forms of intellectual inquiry. His publications include Philosophy and the Mirror of Nature (1979), Con¬ sequences of Pragmatism (1982), and Contingency, Irony and Solidarity
(1989).
Rosa, Salvator (b. June 20, 1615, Arenella, Sicily, Spanish Habsburg—d. March 15, 1673, Rome, Papal States) Italian painter and etcher. He studied in Naples, where he came under the influence of Jose de Ribera, but most of his career was spent in Rome, with an interlude in Florence under the patronage of a Medici cardinal. His landscapes, marine paintings, and battle scenes are known for their picturesquely wild, romantic qualities. A flamboyant personality, he was also an accomplished poet, satirist, actor, and musician.
Rosario City (metro, area pop., 1999 est.: 1,000,000) and river port, east-central Argentina, on the Parana River. Founded in 1725, it began to develop into a major city in the late 19th century. In 1819 the city was burned by revolutionaries. In 1860 it welcomed domestic and foreign oceangoing ships to its natural harbour, which became a major port. One of Argentina’s largest cities, it exports grain, meat, and lumber. It is also an industrial city, producing steel, automobiles, and agricultural machin¬ ery, and it is an educational centre.
rosary Religious exercise in which prayers are recited and counted on a string of beads or knotted cord, which is also called a rosary. Many of these devices are highly ornamental and incorporate jewels. The practice of using a rosary or “counting beads” occurs widely in world religions, including Christianity, Hinduism, Buddhism, and Islam. In Christianity, the most common rosary is that of the Virgin Mary. Its origin is uncer¬ tain, but it is associated with St. Dominic and reached its definitive form in the 15th century.
rosary pea or Indian licorice Tropical plant ( Abrus precatorius ; family Leguminosae). Its hard, red and black seeds, though highly poi¬ sonous, are strung into necklaces and rosaries in India and other tropical areas. In India the seeds are also used as a unit of weight ( ratti ).
Rosas Vro-sasV Juan Manuel de (b. March 30, 1793, Buenos Aires, Viceroyalty of the Rfo de la Plata—d. March 14, 1877, Southampton, Hampshire, Eng.) Argentinian military and political leader. Born to a wealthy family, Rosas emerged a federalist hero from the country’s long civil war and was made governor of Buenos Aires in 1829. He left office in 1833 to pursue a war against the Indians, and in 1835 he again became governor of Buenos Aires, this time with dictatorial powers. He was the quintessential caudillo, a tyrant who cultivated a fiercely loyal personal following and ruled by intimidation and patronage. Despite his professed allegiance to federalism, he estab¬ lished central control over all of Argentina until he was finally over¬ thrown in 1852 and forced to flee to England.
rose Any of about 100 species in the genus Rosa (family Rosaceae) characterized by their beautiful, fra¬ grant flowers. Rosa species are prob¬ ably the most widely recognized and universally favoured of ornamental flowering plants. Hundreds of vari¬ eties are cultivated in all types of set¬ tings, and there are many hybrids.