question_answer

Assume that you are trying to insert a gene from human DNA into a plasmid and someone gives you a preparation of human DNA cut with restriction endonuclease A. The human gene you are studying has sites on both ends for restriction endonuclease B. You have a plasmid with a single site for B, but not for A. Your best strategy would be to:

A)  Cut the plasmid with restriction endonuclease A and insert the human DNA cut with restriction endonuclease B into the plasmid.

B)  Cut the plasmid twice with restriction endonuclease B and ligate the two fragments onto the ends of the human DNA fragments cut with restriction endonuclease A.

C)  Cut the human DNA again with the restriction endonuclease B and insert these fragments into the plasmid cut with the same enzyme.

D)  Cut the plasmid with restriction endonuclease A and insert the human DNA cut with restriction endonuclease A into the plasmid.