A researcher wanted to test the effectiveness of a new antibiotic on Streptococcus pyrogenes, the species of bacteria that causes strep throat. Bacteria were added to dish 1, dish 2, and dish 3. A disk soaked in the new antibiotic was then placed in dish 2. Dish 3 was set up as the
control. The dishes are shown in the diagram below.

59 State one appropriate hypothesis for this experiment. [1]

60 All three dishes were placed in an incubator at 37°C for 24 hours. The results for dish 1 are shown to the right.

Complete (color in) the diagram of dish 2 below to represent an example of experimental results that would support your hypothesis. (Use the “Draw” tab in Microsoft Word)

Explain how your diagram supports your hypothesis. [1]

61 Describe how the disk in dish 3 should be prepared so it can serve as the control for
this experiment. [1]