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Methods

3.) A loop was used to collect a sample to plate. Each plate would be sent to the incubator to grow bacteria overnight, Each test tube and plate was labelled accordingly, including drawing/labeling the four quadrants, each one a separate sample.

4.) The next day, the number of colonies grown be each particular sample would be recorded numerically and images would be taken to then analyze the results and conclude the effect of temperature on bacteria growth.

Set-Up

Variables tested- In the experiment, the variable we tested was the temperature the E. Coli was exposed to; since we manipulated this variable, we were able to determine if this led to a faster or slower rate of growth in our E. Coli samples.

How results were measured- Our results were measured both qualitatively--through capturing visual images of the samples’ colonies-- and quantitatively--through counting the number of colonies grown by each sample. 

1.) E. Coli bacteria were placed into 12 plastic test tubes and mixed with a “nutrient broth”, which were then placed into the class’s incubator overnight. Each test tube was labelled accordingly.

2.) The day after, the bacteria were ready to be plated onto specially-prepared plates. A pipet was used to transfer the mix of nutrient broth and the E. Coli to a glass test tube. It was then heated by a hot plate at xC (16C, 22C, or 37C). This same process was performed for 2 total trials for the 16C, 3 total trials for the 22C, and 3 total trials for the 37C were collected. 

Variables Tested 

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Results Measured

Experimentation