|Description:||This image depicts four test tubes each containing triple sugar iron agar (TSI) medium. Test tube 1 only contained the agar medium, hence was uninoculated. Test tube 2, contained medium that was inoculated with Shigella sp. bacteria. Test tube 3 contained medium inoculated with Providencia sp. bacteria. Test tube 4 contained medium inoculated with Pseudomonas sp. bacteria.|
Note the differing morphology when comparing the bacterial cultures which took shape after the media had been inoculated, and were incubated for an unknown amount of time, and at an unknown temperature.