In this lab we collected bacteria from different areas in the school including our hands, toilets, sinks, door handles, keyboards, and lockers. We used petri dishes and divided them into six parts. We used sterile cotton swabs to swipe all of our bacteria, and we dipped it into a different liquid for each area to see which worked the best. We used our hands to swap the skin bacteria. The first trial was dipped in distilled water, and the second was dipped in isopropyl alcohol. Rubbing alcohol is an antibacterial product called an antiseptic, because you can use it on surfaces of living things, such as our skin. We use disinfectants on non-living things. For the third trial on skin, we washed our hands but didn't dry them allowing the cotton swab to collect any bacteria left over on our fingers.
After we swabbed each bacteria we then streaked our swab onto our petri dish in the appropriate section. After we used the skin bacteria, we proceeded onto surface bacteria. This is where the toilets, sinks, and door handles come in handy. My surface that I used for bacteria was the toilet in the high school girl's lockeroom.
I used the same two liquids for each trial that I used for my skin, except I also used bleach for my third trial. After I allowed the bacteria to grow for 24 hours in the incubator, the bacteria from the toilet using the distilled water had grown the most. The alcohol and bleach evidently was able to kill some of the bacteria, but the water did not. Therefore, I believe the disinfectants worked better than the antiseptic.
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