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Germ plasm ( German: Keimplasma) is a biological concept developed in the 19th century by the German biologist August Weismann. It states that heritable information is transmitted only by germ cells in the gonads (ovaries and testes), not by somatic cells.
The Weismann barrier, proposed by August Weismann, is the strict distinction between the "immortal" germ cell lineages producing gametes and "disposable" somatic cells in animals (but not plants), in contrast to Charles Darwin's proposed pangenesis mechanism for inheritance.
His main contribution involved germ plasm theory, at one time also known as Weismannism, according to which inheritance (in a multicellular animal) only takes place by means of the germ cells—the gametes such as egg cells and sperm cells.
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.
- The Editors of Encyclopaedia Britannica
23 mag 2014 · Weismann proposed the theory of the continuity of germ-plasm, a theory of heredity. Weismann postulated that germ-plasm was the hereditary material in cells, and parents transmitted to their offspring only the germ-plasm present in germ-cells (sperm and egg cells) rather than somatic or body cells.
26 gen 2015 · In The Germ-Plasm, Weismann proposed a theory of heredity based on the concept of the germ plasm, a substance in the germ cell that carries hereditary information. The Germ-Plasm compiled Weismann's theoretical work and analyses of other biologists' experimental work in the 1880s, and it provided a framework to study development ...
In 1883 the great German biologist August Weismann proposed the “germ-plasm” theory of heredity. The germ-plasm theory states that an organism’s cells are divided into somatic cells (the cells that make up the body) and germ cells (cells that produce the gametes).
