A foreign DNA and plasmid cut by the same restriction endonuclease can be joined to form a recombinant plasmid using
- Eco RI
- Polymerase III
- Ligase
- Taq polymerase
Answer
(3) Ligase
Solution
Cutting the foreign DNA and the vector with the same restriction enzyme produces complementary sticky ends.
⇒ The sticky ends pair by hydrogen bonds, and the enzyme DNA ligase seals the sugar–phosphate backbone to form the recombinant DNA.
⇒ EcoRI cuts DNA; DNA polymerase III and Taq polymerase synthesise DNA.
Answer: (3)