REPLICATION Of DNA

one of the most important properties of DNA is that it forms its additional identical copies. The process of forming its replica copy is called replication.Replication is the basis of evolution of all morphologically complexed forms of life. Howard and Pelc demonstrated that in eukaryotes replication occurs during interphase between mitotic cycles and also during interphase are seperated into two daughter cells, and thus equal number of chromosomes is maintained. However, replication does not occur during entire anaphase but is confined only to synthesis (s) phase. There is a post-mitotic gap(G1) between the telophase and S phase. A second premitotic gap (G2) is between the S phase and prophase. Only S phase involves replication process. The G1 phase is most variable and in many eukaryotic cells it is completed within 3 to 4 hours or even months depending on physiological conditions. Mostly DNA synthesis is accomplished in 7 to 8hours. In bacteria growing at long phase, DNA synthesis occurs from the time a cell originates to it give rise to daughter cells. It is networthy that bacteria divide only through binary fission.

In general DNA carries out to important functions such as heterocatalytic function and autocatalytic function. The heterocatalytic function is protein synthesis directed by DNA, and autocatalytic function is the synthesis of its own DNA into replica copies. However replication of DNA in prokaryotes differ from that of eukaryotes.