| 释义 |
ˌsemi-conˈservative, a. Biochem.
[semi- 1.]
Of the replication of nucleic acid: such that one complete strand of each double helix is directly derived from its parent.
The term was originally proposed (see quot. 1957) to designate a class of models of the replication of DNA; it is now accepted that its true mechanism of replication falls in this class.
1957Delbruck & Stent in McElroy & Glass Chem. Basis of Heredity 707 The considerable number of proposed schemes may be divided into three general classes as conservative, semi-conservative, and dispersive. Ibid. 709 Semi-conservative mechanisms are those which conserve the atomic identity of single chains of the parental DNA duplex, although effecting a permanent separation of the two chains from each other in the course of replication. 1970Nature 7 Nov. 522/1 There is good evidence that DNA replication is semi-conservative and involves separation of the two strands which then act as templates. 1976P. Collard Devel. Microbiol. viii. 106 Semi-conservative replication thus provided a possible answer to the riddle of the stability of the genome from generation to generation.
Hence ˌsemiconˈservatively adv.
1966Jrnl. Molecular Biol. XV. 372 Since all the DNA is replicated semiconservatively..such a segregation pattern could arise most simply if every chromosome contained all its DNA within a single molecule. 1979Nature 3 May 75/2, pBR322 DNA replicates semiconservatively and completely in a crude lysate of E. coli. |