Dictionary > Gemmule

Gemmule

Definition
noun, plural: gemmules
(botany) A small gemma; a bud produced by gemmation.
(zoology) A mass of cell capable of remaining dormant then later develops into a new individual.
(evolution) A hypothetical unit formerly assumed to act as bearer of hereditary attributes as postulated by Charles Darwin in his theory of pangenesis.
Supplement
In botany, gemmules refer to the asexual reproductive structures in some plants, such as the buds of mosses and the spores of hydra.
In zoology, gemmules are produced by sponges which can be dormant through the winter, and then later develop into new sponge.
In pangenesis, gemmules are imagined particles of inheritance conceptualized by Charles Darwin to explain heredity. Gemmules are thought to be shed from every part of the body, circulate freely in the bloodstream and move to the gonads where they accumulate in the germ cells. They are supposed to be transmitted from the parent to the offspring in the dormant state until atavism occurs. Gemmules are also called pangenes.
Word origin: French, from Latin gemmula, diminutive of gemma, bud.
See also: pangenesis.


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