Fig. 6

A small group’s revised model to explain how Addie’s condition changed as the bacteria changed within her. The first column in the model shows how Addie is feeling as time elapses. The next column marks the generation of bacteria. The numbers in the next column indicate the relative size of the bacteria population as a whole, followed by a graph of the proportion of the resistant bacteria (labeled R in the diagram, the red bar in the graph) and nonresistant bacteria (labeled NR in the diagram, represented by the green bar in the graph) in the population. The graph and numbers reflect the step-by-step model that students drew out mapping the bacteria inside Addie’s body. An X on the bacterium means the antibiotic killed the bacterium. A branch means the bacterium divided. Of course only surviving bacteria reproduced. The number in the next generation is the number of bacteria minus the ones that died after the survivors reproduced