germ-plasm theory

germ-plasm theory
Concept of the physical basis of heredity expressed by the biologist August Weismann (1834–1914).

It claimed that germ plasm, which Weismann believed to be independent from all other cells of the body, was the essential element of germ cells (eggs and sperm) and was the hereditary material passed from generation to generation. First proposed in 1883, his view contradicted Lamarck's then-prevalent theory of acquired characteristics. Though its details have been altered, its idea of the stability of hereditary material is the basis of the modern understanding of physical inheritance.

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      concept of the physical basis of heredity expressed by the 19th-century biologist August Weismann (Weismann, August (Friedrich Leopold)) (q.v.). According to his theory, germ plasm, which is independent from all other cells of the body (somatoplasm), is the essential element of germ cells (eggs and sperm) and is the hereditary material that is passed from generation to generation. Weismann first proposed this theory in 1883; it was later published in his treatise Das Keimplasma (1892; The Germ-Plasm: A Theory of Heredity). This view contradicted Lamarck's theory of acquired characteristics, which was a prevalent theory of heredity of the time. Although the details of the germ-plasm theory have been modified, its premise of the continuity of hereditary material is the basis of the modern understanding of the process of physical inheritance.

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Universalium. 2010.

См. также в других словарях:

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  • Germ plasm — or polar plasm is a zone found in the cytoplasm of the egg cells of some model organisms (such as Caenorhabditis elegans , Drosophila melanogaster , Xenopus laevis ), which contains determinants that will give rise to the germ cell lineage. As… …   Wikipedia

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  • August Weismann — Friedrich Leopold August Weismann (Birth. January 17, 1834 in Frankfurt am Main; Death. November 5 , 1914 in Freiburg im Breisgau, ) was a German biologist. [ [http://www.nndb.com/people/747/000091474/ August Weismann ] at www.nndb.com] Ernst… …   Wikipedia

  • Weismann, August (Friedrich Leopold) — ▪ German biologist born Jan. 17, 1834, Frankfurt am Main died Nov. 5, 1914, Freiburg im Breisgau, Ger.       German biologist and one of the founders of the science of genetics, who is best known for his opposition to the doctrine of the… …   Universalium

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  • heredity — /heuh red i tee/, n., pl. heredities. Biol. 1. the transmission of genetic characters from parents to offspring: it is dependent upon the segregation and recombination of genes during meiosis and fertilization and results in the genesis of a new… …   Universalium

  • Heredity — • The offspring tends to resemble, sometimes with extraordinary closeness, the parents Catholic Encyclopedia. Kevin Knight. 2006. Heredity     Heredity      …   Catholic encyclopedia


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