Peter Le's Bacteria

My bacteria was exposed in my room for around 40 minutes to an hour. The temperature in my room is usually warm and hot, however, my AC is usually turned for about an hour to cool down the room. As i turn it off, I exposed my petri dish. The exposure started on September 16th. As time passed and bacteria grew, I realized there were fuzzy stuff growing. As it started growing, there were less and less bacteria growth each day. During the exposure of the petri dish, the temperature was never constant.

Bacteria and Fungi Growth Progess

Results #1: Growth of a Single Colony

Growth of a Single Colony

Results #2: Total Number Of Colonies

Discussion / Conclusion

    In the lab, I exposed my petri dish for around 40~60 minutes a day for 15 days. As it grew, I noticed it was an example of logistic growth. Temperature was a problem. Some days my AC was turned on and some it wasn't. The temperature was not constant all the time. It grew around 10~30 bacteria each day for a couple of days, then started to grow only about 6~10. It grew rapidly then started to grow slowly and slowly. As more and more bacteria grew, i realized that not only had it started growing slower, but the size was also becoming smaller. During Day 15, I realized that there were a lot of small colonies. It lead me to the idea that there were little nutrients and that they were reaching their carrying capacity. I hypothesized that the amount of nutrients becomes more scarce as more and more bacteria grew. 

What I've Learned

    I learned many things about colonies throughout this lab. I learned that nutrients and carrying capacity affects the colony a lot. If there were an infinite amount of nutrients, the colony would grow a massive size. There would be no competition  Nutrients are one of the main keys that keeps a colony to a good size in which they can't take over the Earth. Nutrients lead to competition between colonies. It is fought for so that the colony can keep on growing. If there isn't a lot of nutrients, then there would only be a little numbers in the colony barely surviving.