Remak , Robert
- (1815–1865) Polish–German embryologist and anatomistRemak, born the son of a shopkeeper in Posen (now in Poland), obtained his MD from the University of Berlin in 1838. Although he spent most of his career there and despite his considerable scientific achievements Remak was denied appropriate promotion and a teaching position because he was a Jew.In 1838 Remak finally disposed of the ancient myth, probably dating back to Alcmaeon of Croton, that nerves were hollow tubes. In the long history of medicine they had been authoritatively described by centuries of keen-eyed anatomists as carrying various spirits, fluids, and airs. Even the introduction of the microscope in the 17th century made no difference. It was left to Remak to point out that the nerve fiber is not hollow, but solid and flat.In 1844 Remak discovered ganglion cells in the heart, thus showing that it could maintain a rhythmic beat independently of the central nervous system. He further noted that certain fibers of the nervous system, the sympathetic fibers, have a distinctly gray color rather than the more common white. They in fact lack the myelin sheath enclosing other nerve fibers.In the mid 1840s, in collaboration with Johannes Müller, Remak made a major revision to the orthodox embryology of Karl von Baer. They reduced the four germ layers of von Baer to three by taking the two middle layers as only one. They also at this point introduced the modern terminology of endoderm, mesoderm, and ectoderm.It was also Remak who, in 1841, first fully described the process of cell division. He went on to insist that the nucleus was a permanent feature of the cell even though it did become less noticeable after cell division. By 1855 Remak was ready to assert the general conclusion implicit in much of the early cell theory: that the production of nuclei or cells is really only division of preexisting nuclei or cells.
Scientists. Academic. 2011.
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Remak, Robert — born July 26, 1815, Posen, Prussia died Aug. 29, 1865, Kissingen, Bavaria German embryologist and neurologist. He discovered and named the three germ layers of cells that develop in the early embryo: the ectoderm, mesoderm, and endoderm. He also… … Universalium
Remak, Robert — (26 jul. 1815, Posen, Prusia–29 ago. 1865, Kissingen, Baviera). Embriólogo y neurólogo alemán. Descubrió y denominó las tres capas germinales de células que se desarrollan en el embrión temprano: ectoderma, mesoderma y endoderma. También… … Enciclopedia Universal
Robert Remak (Arzt) — Robert Remak Robert Remak (* 26. Juli 1815 in Posen; † 29. August 1865 in Bad Kissingen) war ein deutsch jüdischer Arzt, Zoologe, Physiologe und Neurologe. Remak gilt als Begründer der modernen Embryologie. Er beschrieb 1842 die drei Keimblätter… … Deutsch Wikipedia
Robert Remak — Saltar a navegación, búsqueda Robert Remak Nacimiento 26 de julio de 1815 Fallecimiento … Wikipedia Español
Remak — Remak, Robert, Nervenarzt, geb. 26. Juli 1815 in Posen, 1859 Prof. in Berlin, gest. 29. Aug. 1865 in Kissingen, entdeckte die Remakschen (marklosen) Nervenfasern u.a., Begründer der Elektrotherapie. – Sein Sohn Ernst Julius K., geb. 26. Mai 1849… … Kleines Konversations-Lexikon
Remak's fiber — Re·mak s fiber rā .mäks n an unmyelinated nerve fiber called also fiber of Remak Remak Robert (1815 1865) German neurologist and embryologist. Remak published his first studies on the fine structure of nerve tissue in 1836 and published his… … Medical dictionary
Robert — /rob euhrt/, n. 1. Henry Martyn /mahr tn/, 1837 1923, U.S. engineer and authority on parliamentary procedure: author of Robert s Rules of Order (1876, revised 1915). 2. a male given name: from Germanic words meaning glory and bright. * * * (as… … Universalium
Robert — (as used in expressions) Adam, Robert Aldrich, Robert Altman, Robert (B.) Ashe, Arthur (Robert), Jr. Baden Powell (de Gilwell), Robert Stephenson Smyth, 1 barón Bakewell, Robert Baldwin, Robert Ballard Robert D(uane) Bly, Robert (Elwood) Borden,… … Enciclopedia Universal
Robert Remak — Robert Erich Remak (* 14. Februar 1888 in Berlin; † 13. November 1942 in Auschwitz) war ein deutscher Mathematiker. Er ist bekannt für die Remaksche Zerlegung einer Gruppe, außerdem arbeitete Remak in der Zahlentheorie, Potentialtheorie und der… … Deutsch Wikipedia
Robert Remak — Portrait de Robert Remak (1815 1865) Naissance 26 juillet 1815 … Wikipédia en Français