This figure shows the restriction endonuclease, Eco RI, attached to plasmid DNA. See more images from Atomic Force Microscopy. (Source: Digital Instruments.)

This figure shows restriction fragment patterns of Escherichia coli O157:H7 isolates from Washington State. Samples were isolated from apple juice and from two groups of patients. Which patients contracted their E. coli infections from the contaminated apple juice?

This figure shows restriction fragment patterns for 5 DNA samples. Which suspect (A -- D) matches the Crime Scene (CS) DNA?