Class 12th Biology 2014 Set2 Delhi Board Paper Solution
Question 18
Write the role of Ori and 'restriction' site in a cloning vector pBR322.
Answer
Ori - It is a genetic sequence that acts as the initiation site for replication of DNA. Any fragment of DNA, when linked to the ori region, can be initiated to replicate.
Restriction site - It is the recognition site for restriction enzymes (such as EcoRI, Hind III, PvuI, BamHI, etc.). Recognition sites are the genetic sequences from where the restriction enzymes cut the DNA.
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