The basic scheme of the essential steps involved in the process of recombinant DNA technology is summarized below in the form of a flow diagram. Study the given flow diagram and answer the questions that follow.
(a) Name the enzyme used in Step-1 to join the cut plasmid and alien DNA.
(b) State the technical term used for Step-3.
(c) Justify the use of the same Restriction Enzyme EcoRI to cut both the vector DNA and the alien DNA.
The basic scheme of the essential steps involved in the process of recombinant DNA technology is summarized below in the form of a flow diagram. Study the given flow diagram and answer the questions that follow.
(a) Name the enzyme used in Step-1 to join the cut plasmid and alien DNA.
(b) State the technical term used for Step-3.
(c) Justify the use of the same Restriction Enzyme EcoRI to cut both the vector DNA and the alien DNA.
Show Hint
Solution and Explanation
(a) The enzyme used in Step-1 is DNA ligase. It joins the sticky ends of the vector DNA and the alien DNA to form a recombinant DNA molecule.
(b) The technical term for Step-3 is transformation, which is the process of introducing recombinant DNA into the host cell (E. coli).
(c) Using the same restriction enzyme (EcoR I) to cut both vector and alien DNA ensures that both fragments have complementary sticky ends. This compatibility facilitates the easy and specific joining of the DNA fragments using DNA ligase, ensuring successful recombination.
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