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August weismann Biography

August Weismann

(Frankfurt on the Main, 1834-Freiburg im Breisgau, 1914) German biologist, famous for his theory of germ plasm.He studied at the University of Göttingen, after which he worked for some time in a hospital in Rostock.In order to expand his training, in 1858 he moved to Vienna, where he stayed for a year; later he went to Italy and the following year to Paris.In 1863 he began his studies in zoology at the University of Freiburg, where he also taught between 1866 and 1912; he was professor of Zoology and Comparative Anatomy at this university.He also directed the Museum of Zoology.

August Weismann

His first research was devoted to experimental zoology and published valuable works on the development of Diptera and on the sexuality of hydromedusae.But his most important investigations in the field of biology focused on the origin of species, and led him to develop the Germ Plasma Theory of Heredity , which denied Lamarck's concept that Acquired characters are transmitted from father to son in just one generation, although he admitted Darwin's principle of natural selection.

Weismann supported the theory that the body is divided into germ cells, which can transmit hereditary information, and somatic cells (somatoplasm), which cannot; and that germ plasm, formed by the fusion of the ovum with the sperm, establishes a solid continuity through the generations.Therefore, a new conception of biological inheritance was developed based on the immortality of the germ plasm, which can be related to the rediscovery of Mendel's laws and the experiments of Hugo de Vries.

Later, germ plasm was identified with chromosomes and DNA (deoxyribonucleic acid), and the reduction of genetic material in progenitor cells (meiosis) was also verified.He wrote numerous works in which he made known the results of his studies.It is worth mentioning some such as Studies on the theory of descent (1875-76), Die Kontinuität des Keimplasmas als Grundlage einer Theorie der Vererbung ('The continuity of the germ plasm as a basis of a theory of heredity ', 1885), Über Germinal-selektion (' On germinal selection ', 1896) and Studien zur Deszendenztheorie (' Studies on heredity ' , 1902).His interest in zoology is reflected in the works The embryology of Diptera (1865) and The origin of the sex cells of the hydromedusae.

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