Petri Dish Experiment

On Tuesday (yesterday) and today, Josh introduced me to a new experiment. For weeks I have been testing to see how bacteria reacted, if possible, to corn oil. After several studies, I found that for the most part all the species of bacteria that I chose ranging from E. coli to Bacillus subtilis. I immediately noticed a sudden change of pink color in the tubes compared to Enterobacter aerogenes. However, it becomes strange that a particular bacteria took days or even a week to show results while these other species of bacteria had five-second effects.

This is when a new experiment arose. This time, I would use six blank petri dishes and then add certain key ingredients.The purpose of this experiment was to apply two different species of bacteria to four petri dishes with distilled water or salt water and oil applied. I had to do some background research to find how to make seawater (my original task), but we did not have the necessary ingredients to make it at the moment. Instead, I found how to make 'seawater'.

Preparation

1. To make table 'seawater', have 35 grams of Kosher salt and apply it to a contained 965g of distilled water.
2. Stir the water and the salt until there are no salt particles present. 
3. Next, apply distilled water into three petri dishes, enough so that there are no open gaps. 
4. Repeat step 3 with seawater. 
5. Apply 5 microlitre of Crisco oil to petri dishes (2 labeled with seawater and 2 labeled distilled). [One petri dish will only contain DI H20 and Seawater to be used as control plates.]
6. Wait for 20 minutes for any spreading of the oil.
7. With a thin ruler, measure the diameter of the round oil shape for each petri dish. 
8. Apply one drop of designated bacteria to the designated plates. 
9. Carefully placed the plates in an incubator and wait for 24 hours. 

*I also replaced Cisco oil with motor oil, but did the exact same steps. 

Results

The ones with Cisco oil: I noticed that the plates with distilled water formed a small circle of only .5 centimeter while the plates containing seawater had more of a spread with the oil and the measure of the diameter was 1 centimeter.

The ones with motor oil: I saw immediate dispersion of the oil into the water. I waited for 20 minutes to see how it would form and then apply results.Since the oil was still segregated, I measured the default length of the diameter of the petri dish which is 14 cm. 

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It has been two days with this experiment. There were some flaws and little success, but I will see tomorrow if the newly added plates containing a couple of bacteria have shown results.

*I also submitted my abstract, but before that I had to continuously check for errors and make sure that it was solid. I was grateful for the feedback and help that I received to make it turn out as it is now.