Explain why it is necessary to use the same restriction enzyme to cut the desired gene from the source and to cut the plasmid. include a drawing or diagram in your answer.

It is necessary because of the base pairing between the desired gene and plasmid

Explanation:

Restriction enzymes are enzymes that recognize the specific DNA sequence-restriction site, double-stranded cut DNA and produce ends with a single-stranded overhang. The overhangs of the plasmid can stick together with overhangs of gene of interest by complementary base pairing.  Joining of ovarhangs is done by the enzyme DNA ligase.