Figure 6.14: This image shows a line drawing of a plasmid. The plasmid is drawn as two
concentriccirclesthatareveryclosetogether, withtwolargesegmentsandonesmallsegment
depicted. The two large segments (1 and 2) indicate antibiotic resistances usually used in
a screening procedure, and the small segment (3) indicates an origin of replication. The
resulting DNA is a recombinant DNA molecule. ( 3 )
Figure 6.15: A step-by-step depiction of the cloning of the insulin gene. The plasmid is
opened up with restriction enzymes and the gene of interest (human cDNA) is inserted into
the plasmid with complementary linkers, producing the recombinant plasmid. The plasmid
is transfected into bacterial cells, where the human protein is produced. ( 17 )