In this investigation, E. coli cells are exposed to plasmids containing a gene for resistance to ampicillin. If the susceptible E. coli bacteria incorporate the foreign DNA, they will become ampicillin resistant. Which of the following statements are true?

Select all that apply.
A. Transformation follows the uptake of foreign proteins into a cell.
B. Plasmid DNA containsgenes essential for normal function.
C. Transformation occurs when foreign genes are introdicued into a host cell.
D. Bacterial cells have several linear chromosomes.
E. Plasmids can be engineered to carry foreign DNA.