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 plasmid vector and donor gene (fragment of DNA) are cleaved by the same restriction enzyme, it will result in DNA fragments with sticky ends. These both sticky ends can be later joined to form recombinant DNA by action of DNA ligases, hence in recombinant DNA technology, a plasmid vector must be cleaved by the same enzyme that cleaves the donor gene.

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