This figure illustrates bacterial growth in the gut using three approaches. It is a screenshot taken from the interactive activity used in Activity 6. On the top left the gut is illustrated as a pink circle. Bacteria are illustrated as small blue (antibiotic sensitive) and red (antibiotic resistant) circles. There are many more blue than red circles. On the top right the proportion of antibiotic sensitive (blue) and antibiotic resistant (red) bacteria is shown in a bar graph. The horizontal axis is marked sensitive and resistant. The proportion of sensitive bacteria is higher than the proportion of the resistant bacteria. The bottom graph shows the growth of sensitive and resistant bacteria over time. The horizontal axis is labelled time (days) and marked from 0 to 8 in intervals of 1. Two grey dots indicate the addition of antibiotics. The vertical axis is labelled number of bacteria. The sensitive bacteria (in blue) increase gradually from 0 to 2.5 day and then drop steeply when antibiotics are added. The number of resistant bacteria remains low.