Er

Er, symbol for the element erbium.

Membrane system within the cytoplasm of a eukaryotic cell (see eukaryote), important in the synthesis of proteins and lipids. The ER usually makes up more than half the membrane of the cell and is continuous with the outer membrane of the nuclear envelope (see nucleus). There are two distinct regions of ER: the rough ER, or RER (so called because of the protein-synthesizing ribosomes attached to it), and the smooth ER (SER), which is not associated with ribosomes and is involved in the synthesis of lipids and the detoxification of some toxic chemicals.

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(born May 31, 1819, West Hills, Long Island, N.Y., U.S.—died March 26, 1892, Camden, N.J.) U.S. poet, journalist, and essayist. Whitman lived in Brooklyn as a boy and left school at age 12. He went on to hold a great variety of jobs, including writing and editing for periodicals. His revolutionary poetry dealt with extremely private experiences (including sexuality) while celebrating the collective experience of an idealized democratic American life. His Leaves of Grass (1st ed., 1855), revised and much expanded in successive editions that incorporated his subsequent poetry, was too frank and unconventional to win wide acceptance in its day, but it was hailed by figures such as Ralph Waldo Emerson and exerted a strong influence on American and foreign literature. Written without rhyme or traditional metre, poems such as “I Sing the Body Electric” and “Song of Myself” assert the beauty of the human body, physical health, and sexuality; later editions included “Crossing Brooklyn Ferry,” “Out of the Cradle Endlessly Rocking,” and the elegies on Abraham Lincoln “O Captain! My Captain!” and “When Lilacs Last in the Dooryard Bloom'd.” Whitman served as a volunteer in Washington hospitals during the Civil War. The prose Democratic Vistas (1871) and Specimen Days & Collect (1882–83) drew on his wartime experiences and subsequent reflections. His powerful influence in the 20th century can be seen in the work of poets as diverse as Pablo Neruda, Fernando Pessoa, and Allen Ginsberg.

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(born Dec. 5, 1901, Chicago, Ill., U.S.—died Dec. 15, 1966, Los Angeles, Calif.) U.S. animator and entertainment executive. In the 1920s he joined with his brother Roy and his friend Ub Iwerks (1901–71) to establish an animation studio. Together they created Mickey Mouse, the cheerful rodent—customarily drawn by Iwerks, with Disney providing the voice—that starred in the first animated film with sound, Steamboat Willie (1928). The brothers formed Walt Disney Productions (later the Disney Co.) in 1929. Mickey Mouse's instant popularity led them to invent other characters such as Donald Duck, Pluto, and Goofy and to make several short cartoon films, including The Three Little Pigs (1933). Their first full-length animated film, Snow White and the Seven Dwarfs (1937), was followed by classics such as Pinocchio (1940), Fantasia (1940), and Cinderella (1950). A perfectionist, an innovator, and a skilled businessman, Walt Disney maintained tight control over the company in both creative and business aspects. He oversaw the company's expansion into live-action films, television programming, theme parks, and mass merchandising. By his death in 1966, Disney had transformed the family entertainment industry and influenced more than one generation of American children.

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Er or ER may refer to:

Medicine

• Emergency room, a department of a hospital used for quick and needed medical attention
• Estrogen receptor, a member of the nuclear hormone family of intracellular receptor

Television

• ER (TV series), a 1994–2009 NBC medical drama
• E/R, a 1984–1985 CBS sitcom

Science and computing

• Engineer, a lawful holder of a degree in engineering
• Endoplasmic reticulum, a type of organelle in cell biology
• Estrogen receptor, a type of receptor in biochemistry
• Equine Exertional Rhabdomyolysis, a disease found in horses
• Erbium, a chemical element
• Entity-relationship model or diagram, a conceptual data model used in software engineering and database design
• Relative static permittivity, a concept in chemistry represented as $epsilon\_r$

Language

• Er (Cyrillic), a letter in the Cyrillic alphabet
• The suffix -er
• A filler word used in dialogue displaying uncertainty
• Third person nominative pronoun in German

Other meanings

• Er (Biblical name)
• ER (Extended Range), a term for missiles or aircraft
• Myth of Er, an analogy in Plato's The Republic
• Eesti Rahvusringhääling, a public broadcasting organization in Estonia
• Earned run, a concept in the game of baseball
• Evidential Reasoning Approach, a concept in Decision Theory
• United Russia, a political party
• Chico Enterprise-Record, a daily newspaper
• Eritrea, an African country (ER ISO 3166-1 alpha-2 code)
• Astar Air Cargo, an airline (ER IATA code)
• Eduardus Rex, Latin initials used by King Edward I through VII
• Elizabeth Regina, initials used by Queen Elizabeth II (only "Regina" is in Latin)