Plasmid

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Plasmid \Plas"mid\, n. (Molecular genetics)
     A piece of DNA, usually circular, functioning as part of the
     genetic material of a cell, not integrated with the
     chromosome and replicating independently of the chromosome,
     but transferred, like the chromosome, to subsequent
     generations of daughter cells. In bacteria, plasmids often


     carry the genes for antibiotic resistance; they are exploited
     in genetic engineering as the vehicles for introduction of
     extraneous DNA into cells, to alter the genetic makeup of the
     cell. The cells thus altered may produce desirable proteins
     which are extracted and used; in the case of genetically
     altered plant cells, the altered cells may grow into complete
     plants with changed properties, as for example, increased
     resistance to disease.
     [PJC]

From WordNet (r) 2.0 [wn]:

  plasmid
       n : a small cellular inclusion consisting of a ring of DNA that
           is not in a chromosome but is capable of autonomous
           replication