Recycle Buds Honors Biology 9/1/13 The growth of Bacteria Purpose; the purpose of this lab was to see how much bacteria would grow on our variables we chose to use. Hypothesis; The dirtier the variable, the more bacteria will grow over time. Materials; 6 Petri dishes Cotton Swabs (Q-tips) Procedure; we started with 6 different Petri dishes that had a sticky yellow-sis substance layered on the bottom. Then, we picked out the variables we were going to use to rub onto the yellow substance.
Lastly, we put soap on one Q-tip, rubbed a Q- IP on unclean hands, fiercely scrubbed Message’s hair with another, rubbed one onto the dirty table, one on the clean table, and then we put hand sanitized on another one. We let the variables stay on the substance for about two days. Data; the soapy Q-tip had the least amount of bacteria on it and the unclean hands had the most. Message’s hair had very small specks of bacteria in large amounts, the table only had a very few large pieces where the clean table actually had quite a lot of bacteria on it s well.
The hand sanitized had a few large and small specks all around the dish. Analysis; after about two days, we saw that the cleaner the variable, soapy Q-tip, clean table, hand sanitized, the less bacteria was grown over time. I think the variable with the most bacteria was unclean hands, which is the most likely because if you don’t wash your hands for more than five minutes, your hands still have most of the same bacteria that you had before you washed them.