Construction of rDNA is possible due to the (A) ability of restriction enzyme to cut DNA at specific sites (B) use of restriction enzyme purified from virus (C) ability of bacteria to carry out transduction (D) ability of DNA ligase to cut DNA at specific site
Option A. The restriction endonucleases cleave the DNA molecules at the specific sites called the restriction sites, that are made of palindromic sequences. If the sequence-specific cuts are not made by the restriction endonucleases, it would become impossible to target the specific gene. The random cuts would result in variable lengths of DNA fragments and the joining of the target gene with vector DNA would have become cumbersome as restriction endonuclease create either the sticky ends or the blunt ends. In both the cases, it is easy to monitor the ligation process. In other words, the r-DNA technology would not have gained the momentum.
