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Investigation to determine the effect of different brands of mouthwashes on microbes

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Biology Investigation Coursework Investigation to determine the effect of different brands of mouthwashes on microbes Results For Pilot with Microccus Liteus When analysing my results, I thought it would be easier to draw an accurate line around the area of the mouthwash sample so that I would be able to measure the zone of clearance accurately using the digital callipers. The area that has been cleared of microbes is the value that I have recorded in the table below. I have used the digital callipers with a reading of 3 s.f to maintain accurate results throughout the experiment. Result No. Mouthwash A Mouthwash B Mouthwash C Mouthwash D 1 6.10 mm 4.13 mm 5.20 mm 1.89 mm 2 7.05 mm 4.69 mm 4.83 mm 2.06 mm 3 6.95 mm 4.93 mm 5.73 mm 1.88 mm ...read more.


Figure 4 shows a close up of one of the samples with arrowheads showing the distance that I measured for each brand of mouthwash using the digital callipers. I have included these photographs for evidence of the results shown in the table for my pilot investigation. When looking at the results table and the zone of Clearance order I can see that Mouthwash A had the highest average zone of clearance followed by Mouthwash C, then B and lastly D. This shows that from the pilot investigation, Mouthwash A was the most effective in destroying the Microccus Liteus microbes. When looking at the average result, it is almost double that of Mouthwash D. Once I had completed this pilot experiment, I then decided to see what the effect of mouthwash would be with another type of ...read more.


1. Mouthwash B 2. Mouthwash C 3. Mouthwash A 4. Mouthwash D Results For Microccus Liteus Result No. Mouthwash A Mouthwash B Mouthwash C Mouthwash D 1 7.30 mm 5.04 mm 7.86 mm 4.21 mm 2 7.81 mm 6.49 mm 7.73 mm 4.50 mm 3 8.45 mm 6.98 mm 7.62 mm 3.38 mm 4 8.72 mm 5.79 mm 7.36 mm 3.47 mm 5 8.64 mm 6.24 mm 6.89 mm 4.95 mm 6 7.94 mm 5.72 mm 6.56 mm 4.13 mm 7 8.58 mm 5.37 mm 7.34 mm 3.91 mm 8 8.63 mm 5.21 mm 6.71 mm 3.86 mm 9 10 11 12 Order of Zone of Clearance of Microbial Decay (Highest to Lowest) 1. Mouthwash A 2. Mouthwash C 3. Mouthwash B 4. Mouthwash D ...read more.

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Here's what a teacher thought of this essay

3 star(s)

*** A reasonable presentation of a pilot study's results, but the purpose of the pilot and the conclusion are unclear. Good photographs are included throughout, but what each represents requires clarification. To improve:
1)Include key descriptive statistics in all tables, and refer to them
2)Draw a conclusion form the data about the effectiveness of different mouthwashes on different bacteria, quoting descriptive statistics like the mean and standard deviation to support statements
3)Clearly state how the trial informs the main plan i.e. how the plan for the main experiment will be altered
4)Follow naming conventions when referring to micro-organisms, and ensure that names are spelt correctly
5)Label all images, tables and graphs with appropriate titles and headings so it is clear what they represent
6)Include an appropriate graph to illustrate key results

Marked by teacher kerry Jackson 24/03/2012

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