Question

In recombinant DNA technology a plasmid vector must be cleaved by

• A. The same enzyme that cleaves the donor gene
• B. Modified DNA ligase
• C. A heated alkaline solution
• D. Four separate enzymes

Answer 1

The correct option is A The same enzyme that cleaves the donor gene

If both the plasmid vector and donor gene (DNA segment) are cut with the same restriction enzyme, it will result in sticky ends. This is because of the special property of restriction enzyme that cuts DNA by identifying a particular palindrome sequence. This sticky ends from vector plasmid and donor DNA are joined by DNA ligase later to form recombinant DNA.

So, the correct option is 'the same enzyme that cleaves the donor gene'.