Background:
The purpose of the antiseptic lab was to show the effectiveness of multiple antiseptics: hydrogen Peroxide, Purell hand sanitizer, Water and Iodine.
The procedure of the lab for the first day involved our group acquiring a cotton swab and using the swab to gather the Propionibacterium acnes (P. acnes) bacteria from various spots around our face, we then grabbed a Petri dish filled only with a thin layer of agar. We proceeded to swab the P. acnes bacteria off of the cotton swab (gently to not break the agar) into the Petri dish. Once we had completed swabbing the P. acnes over the agar we closed the Petri dish, taped over the dish and then wrote our initials on the dish and handed both to Mr.Breines who then put the Petri dishes into an incubator. On the second day of the lab our group was given our day one Petri dish and a new agar filled Petri dish. Our group then sectioned off the new Petri dish into four quadrants. Once we had finished doing that we then proceeded to swab the P. acnes bacteria from the old Petri dish into the new Petri dish. Afterwards we placed a different antiseptic disk into each of the quadrants, then taped the new and old Petri dish up, placed our initials on both and handed them to Mr.Breines. On the third day of the lab our group was given our second Petri dish back to analyze the effectiveness of the antiseptics. An antiseptic is a substance that can inhibit or even stop the growth of bacteria. An inhibition zone (in relation to the current lab) is how large of a circle around the antiseptic substance the bacteria was stopped from growing visibly. The way the inhibition zone relates to the strength of the antiseptic is, the stronger the antiseptic the larger the inhibition zone due to no bacteria growing around the antiseptic. Objectives: The major hypothesis being tested by this lab would be: If we placed varying strength antiseptics within a bacteria infected Petri dish. Then we will see which antiseptic works the greatest. The control group in this experiment would be the inclusion of water as an antiseptic as water is not intended as an antiseptic and would …show more content…
Two ways this experiments data could be considered more reliable is that, there were many runs of the experiment done all with the same parameters and the results are an average of all of the groups’ data. Another reason would that each group could have done the experiment slightly differently and gotten a different result thus showing what changing a variable can do to change the results. One region of bias in this experiment would be that one of the antiseptics used was the Purell hand sanitizer, which is intended to be used on ones hands instead of the face, so it would work less effectively than intended. Two experimental errors our group could have made would be: The agar could have been broken thus preventing bacteria from growing in the gash made. Or our group could have transferred more bacteria to one of the quadrants and not equaled the amount of bacteria in the other quadrants of the Petri