The objective of this unknown project was to discover what microorganism was given to us using knowledge and skills acquired in the lab.
It is important to identify microorganisms so that we can identify what may be causing an illness or a disease. For this project we were given a nutrient plate cultured with two organisms: one gram negative and one gram positive. In order to determine which organisms we were given we had to do a series of tests. To determine which tests we might run we were instructed to create a dichotomous flowchart. I used the information from an expected lab results sheet that was given out to construct my dichotomous flowchart. I organized my chart so that each test I ran on either the gram positive organism or gram negative organism would eliminate possible candidates. It is important to have isolated cultures for this project so that you are able to identify which microorganism you have at the end of this project. A contaminated culture will give you inaccurate results and you will not be able to determine what your unknown bacteria was given to you. Each week I would inoculate a new nutrient agar plate so that I had a fresh specimen to work with. I would then perform a test on each one of my microorganisms, moving down the dichotomous flowchart, eliminating bacteria based on either a positive or negative reaction, until I could not run anymore tests.
Please refer to my dichotomous flowchart.
For the gram negative bacteria and the gram positive bacteria I first performed a gram stain so that I could observe the type, shape and arrangement of the cell. To begin I applied bacteria to a slide. I first added a very small amount of water and a small amount of bacteria by taking a sterilized needle and touching it to the colony on the agar and then to the slide. I then allowed each of slides to dry. Then I heat-fixed both slides by passing them through the flame of...