Unknown Bacteria Essay

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Introduction Identifying unknown bacterium is not only vital to microbiology, but also to the medical and pharmaceutical industries in order to treat disease/infection properly. Bacteria are classified and identified to distinguish among strains and to group them by criteria of interest (1). There are several different procedures that can be utilized to identify a bacterium. This includes the oxidation test, gram stain, and catalase test. The purpose of this lab report is to show the understanding of all procedures used to identify the bacterium, and explain how the given results led to the identification of the unknown bacterium. Cell and colony morphology have been very useful taxonomic features in the differentiation and classification of microorganisms (2). Microscopic examination allows microorganisms to be viewed under magnification, to allow cell morphology to be determined. The most common cell shapes are …show more content…
In order for all results to be correct, aseptic technique must be used throughout the whole lab. Aseptic technique is the collective method of working and maintaining pure cultures, which requires awareness of where microbes are (4). Aseptic technique is important to make sure that the unknown bacteria is a pure culture, because a mixed culture could prevent the correct identification. A mixed culture is one that consist of 2 or more organisms (2). If there is more than one organism in the culture, there is no way to identify which one is the unknown given.
Motility Test. Due to unknown 10 being gram positive, coccus shaped, and a non-sporeformer many bacteria were eliminated. One test that was run to help in differentiating the bacteria is the motility test. The motility test is preformed by taking soft agar, and heavily inoculating it an inoculating needle. The needle will create a line where the bacteria will diffuse out of it is motile. However, unknown 10 did not exhibit any diffusion, classifying it as a non-motile

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