試題詳解

28. In the laboratory experiment, recombinant plasmids are commonly introduced into bacterial cells by:
(A) microinjection.
(B) electrophoresis－a gentle low-voltage gradient draws the DNA into the cell.
(C) transformation－heat shock of the cells incubated with plasmid DNA in the presence of CaCl₂.
(D) infection with a bacteriophage that carries the plasmid.
(E) mixing plasmids with an extract of broken cells.