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Pangenesis   Listen
noun
Pangenesis  n.  (Biol.) An hypothesis advanced by Darwin in explanation of heredity. Note: The theory rests on the assumption, that the whole organization, in the sense of every separate atom or unit, reproduces itself, the cells throwing off minute granules called gemmules, which circulate freely throughout the system and multiply by subdivision. These gemmules collect in the reproductive organs and products, or in buds, so that the egg or bud contains gemmules from all parts of the parent or parents, which in development give rise to cells in the offspring similar to those from which they were given off in the parent. The hypothesis also assumes that these gemmules need not in all cases develop into cells, but may lie dormant, and be transmitted from generation to generation without producing a noticeable effect until a case of atavism occurs. This is an ingenious hypothesis, but now known to be wrong. Although now, a hundred years later, we know that all transmitted genetic information (other than that in plasmids) is contained in the genome of a single cell, scientists are still only beginning to understand the development process.






Collaborative International Dictionary of English 0.48








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"Pangenesis" Quotes from Famous Books



... substance of the cell-nucleus by definite bodies of too small a size to be seen, but constituting together the chromosomes. We may call these innermost representatives of the unit-characters pangenes, in accordance with Darwin's hypothesis of pangenesis, or give them any other name, or we may even wholly abstain from such theoretical discussion, and limit ourselves to the conception of the visible character-units. These units then may be present, or lacking and in the first case active, ...
— Species and Varieties, Their Origin by Mutation • Hugo DeVries

... anticipate how insistently later biologists would demand an explanation that would account for this variation. In his later work, responding to this criticism, Darwin originated a theory which he called Pangenesis. He believed that when an adult animal had responded to his environment and acquired a new character he could transmit this character to his offspring. At that time no one doubted this fact. The whole ...
— The Meaning of Evolution • Samuel Christian Schmucker

... Mr. Darwin's provisional theory of Pangenesis, will sufficiently show that the above is no strange and paradoxical view put forward wantonly, but that it follows as a matter of course from the conclusions arrived at by those who are acknowledged leaders in the scientific world. ...
— Life and Habit • Samuel Butler

... than one Mr. Darwin has drawn heavily upon the scientific tolerance of his age. He has drawn heavily upon time in his development of species, and he has drawn adventurously upon matter in his theory of pangenesis. According to this theory, a germ, already microscopic, is a world of minor germs. Not only is the organism as a whole wrapped up in the germ, but every organ of the organism has there its special seed. This, I say, is an adventurous draft on the power of matter to divide itself and distribute ...
— Fragments of science, V. 1-2 • John Tyndall



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