Unknown Microorganism

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The purpose of performing physiological tests is to figure out certain characteristics of microorganisms or to reach a conclusion on what an unknown microorganism is. It can be also used to determine what is needed for bacteria to be cultured in or on certain media. Culture media can either be liquid or solid, and they can be used to identify certain characteristics of different bacterial species. This is indicated by the growth or lack of growth in or on certain media. Solid media can also be used to isolate organisms and provide a means to observe their morphology (Wiley 55). The purpose of using enzymes to test bacteria is to differentiate and characterize them. Bacteria secrete certain enzymes into the environment, and the presence of these enzymes can be …show more content…
For the culture media tests, synthetic medium, tryptic soy broth (TSB), SF medium, MacConkey agar, and nutrient agar and glucose were used to detect if specific organisms would grow on each media. Synthetic medium is defined media and the contents are exactly known. A positive result would be if one could see cells within the medium after incubation, and means that the the media provides all the nutrients the organism needs to grow. A negative result would be a clear medium without physical signs of growth, and means that the organism requires supplementation. TSB is a complex medium in which the exact chemical composition is unknown. A positive result is positive growth of cells within it, and it shows that the bacteria inoculated within it is aerobic and growth is supported. A negative result is lack of growth and it indicates that the bacteria inoculated within it is not aerobic. The test works by being selective and only allowing the growth of aerobic bacteria. SF broth is a selective medium and is used to select certain organisms by providing the correct environment and nutrients needed to grow. A positive result will elicit a color change of the media from purple to yellow. A negative

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