Mystery TSA Dish Bacteria Post by Ali

Here are images from my Mystery TSA Bacteria Experiment:

Introduction:

The above image summarizes the growth of bacteria over different days. Bacteria are micro organisms that are abundant in places where humans hang out. Whether it be bathroom, hospital, kitchen, tables, or even pens and books, bacteria is all around us. Therefore, to study the existence of bacteria in common places of our biology lab, we were asked to test everyday common things for either positive or negative results. Thus, I opted to study the abundance of bacteria inside my shoe, notebook, my cell phone and the microscope that I use every lab day. A wet cotton swab was used on Day 0 to draw samples from the mentioned places and then they were carefully applied on a Petri Dish. The experiment was set up such that each sample will be studied under two different temperatures: room temperature of around 24 Celsius and under body temperature of 37 Celsius. The prediction was that bacteria studied under 37 Celsius will have a higher growth. The reason for this is that the molecules of bacteria interact better when the temperature is a bit warmer. After the set up of the experiment on Day 0, the experiment was reevaluated on Day 2 and Day 7. 

Day 2:

When the Petri Dishes were evaluated on Day 2, the dish associated with room temperature (24 Celsius) didn't have any sign of bacterial growth. It was a surprise because I was expecting at least some bacterial growth in the sample that was taken from inside the shoe. On the other hand, the dish associated with body temperature (37 Celsius) showed some growth. The sample from microscope had no growth at all, but samples from cell phone and notebook had 2 and 1 colonies respectively. The biggest bacterial growth was observed in the sample from the shoe. There were total 17 countable circular colonies and many other small growths.

Day 7:

Day 7 was by far the most productive for bacterial growth. Even the dish under room temperature (24 Celsius) showed growth in the shoe sample as there were total of 15 big colonies and about 54 small colonies of bacterial growth. There shape was circular and it had yellowish color. Other samples from notebook, microscope and cell phone didn't show any growth which his good news. However, the dish studied under body temperature (37 Celsius) had a tremendous bacterial growth. Bacterial in the shoe sample had expanded to irregular form with dark yellowish color. In addition, the two colonies on the cell phone sample have grown big with circular form and yellow color. The same pattern is observed with the one colony from the notebook sample.

In order to have a more closer look at the growth of bacteria, they were studied under a higher magnification of microscope.

The above image shows bacteria observed under stereo microscope. They are mostly circular with distinct ranges in sizes. Even after some research, unfortunately I wasn't able to identify these bacteria but there are a couple important things associated with this research. First, although bacteria may look scary, but not all of them are harmful. Bacteria is part of our existence and we deal with them almost everyday. Second, bacteria tend to grow better in relatively warmer environment than the room temperature which is 24 Celsius. As experiments showed above, the body temperature of 37 Celsius seems to be the optimum for bacterial growth as their molecules can interact better and efficiently; thus, resulting in better growth.