Plate 1 Plate 2 Plate 3 When an illness is treated with antibiotics, the drugs target every organism, but only kill the susceptible ones. The others are naturally either because of interactions with other organisms or because of mutations. nonresistant more challenging to treat Those members of the population that live on are able to multiply. Only a small portion of the new population of microbes is , making subsequent infections plate 2 The figures above represent parts of the process by which pathogens become increasingly resistant to antibiotics. If drug resistance is represented by the lightly colored microbes, a normal population of organisms is represented by plate 1 Some of these microbes are killed when exposed to antibiotics, as represented by resistant plate 3 The resistant microbes are left to reproduce, yielding the population represented by treatable with the same antibiotic