germ plasm

biology

Also known as: germplasm

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July 16, 2026

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The germ plasm theory, proposed by biologist August Weismann in the 19th century, posits that heredity is carried by a special substance called germ plasm, found in germ cells (sperm and eggs) and separate from the body's other cells. This hereditary material is passed down through generations.12

The term "germplasm" also refers to the genetic material of germ cells or to biological material like seeds or pollen collected for breeding, conservation, or research. Weismann's theory contradicted the idea of acquired characteristics and laid the groundwork for modern understanding of inheritance, even though its specific details have been updated.312

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…19th century, as the “germ plasm” and the “soma.” The germ plasm consists of the essential elements, or genes, passed on from one generation to the next, and the soma consists of the body that may be produced as the organism develops. In more modern terms, Weismann’s germ plasm…
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…19th century, as the “germ plasm” and the “soma.” The germ plasm consists of the essential elements, or genes, passed on from one generation to the next, and the soma consists of the body that may be produced as the organism develops. In more modern terms, Weismann’s germ plasm…
Read More