Unknown Lab Report

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For this lab, the task given was to identify an unknown bacterium of the student’s choosing using Bergey’s Manual, unknown #6 was selected for this lab. Bergey’s Manual is a valuable resource because it provides classification based on rRNA when identifying an unknown bacterium. The purpose of identifying bacteria is for pragmatic purposes- like determining the appropriate treatment for certain infections and diseases. Through Bergey’s Manual, one should be able to successfully identify an unknown bacterium and if it is of normal or transient flora.

To start the process of identifying the unknown bacterium following Bergey’s Manual, a broth, a deep, an agar slant and a streak plate are all inoculated with the unknown bacterium via a needle for the deep and a loop for the broth, agar slant and streak plate. After forty-eight hours all the mediums are examined to see what growth has occurred and the characteristics of growth (if any) are documented. This bacterium was found to be motile from results via the deep, a thin film was visible atop the broth, and sediment was seen at the bottom, with some growth on the agar slant. The growth on the slant appeared to be white in color; almost clear and spiny in its pattern of growth. The growth of bacteria on the streak plate was also successful. The mystery bacteria using the streak plate method appeared yellow and creamy and had successfully colonized each section the loop
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A sample is taken from the broth as well as the streak plate using a sterile loop and heat-fixed onto a clean slide. The slide is then stained using the gram-stain technique to determine whether the bacteria is positive or negative based on the chemical and physical properties of the bacteria's cell wall. After observation, the bacteria were determined to be gram negative since they had stained red. It was also observed that the bacteria were

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