pangenesis

1 definition found

pangenesis - Collaborative International Dictionary of English v.0.48 :

  Pangenesis \Pan*gen"e*sis\, n. [Pan- + genesis.] (Biol.)
     An hypothesis advanced by Darwin in explanation of heredity.
     [1913 Webster]
  
     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.
           [1913 Webster +PJC]