• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

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

Extracts from this document...


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.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Molecules & Cells section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

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

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Molecules & Cells essays

  1. Marked by a teacher

    The Effect Of Temperature on the Respiration Of Yeast.

    5 star(s)

    colourless to pink because if the level of water was above the level of the TTC-yeast mixture and if it heated up quicker than this will have an advantage as it will be hotter and the rate of reaction will be faster because the enzymes will be working faster.

  2. Marked by a teacher

    Investigate the effect of copper sulphate on pepsin activity.

    4 star(s)

    I will then prepare 3 labelled test tubes containing albumen extracted from the white of chicken eggs. I will mix 1cm3 of a concentration of copper sulphate solution with different test tubes containing 4cm3 of albumen, and shake the test tubes to ensure that the two solutions have mixed.

  1. An experiment to find of the isotonic point of root vegetables cells in contents ...

    the root vegetable cylinder will decrease resulting in a decrease in the mass of the root vegetable cylinder. From my results for the potato root vegetable I have found that the potato placed in the sucrose solution of 0.2 and 0.25 became turgid as it mass, length and width increased.

  2. Investigating Catalase Activity in Different Plant Tissues.

    My 2nd main source of experimental error: It was very difficult to cut the piece of carrot into a 1�1�1 cm3, so using this method you will definitely get differences in results if you do the practical on two different sessions.

  1. Investigating how different concentrations of a antibiotic effects the growth of a bacterium.

    and paper towels > Marker pen > Hole punch > 6 Test tubes > Test tube rack > Distilled water > 1 mm syringes > 5 cm3 syringes > Spreader > Ethanol > Callipers II. Before any of the apparatus is to be used the working surface should be cleaned using the disinfectant provided and paper towels.

  2. Investigation for the effect of disinfection on bacterial growth

    of E coli bacteria * 1 inoculating loop * 1 piece of tissue * 1 stop clock * 11 agar plates * 1 marker pen * Sellotape and scissors I carried out a preliminary experiment. This experiment was done initially to determine the type of disinfectant I was going to


    Within the protein, the same process occurs as in the cytochrome complex with the Fe3+ becoming reduced then oxidised to release electrons. Energy released is used to pump more hydrogen ions out of the mitochondrial matrix. The electrons released from cytochrome oxidase are then accepted by oxygen.

  2. To find out how different concentrations of sucrose solution affect the incipient plasmolysis of ...

    mass because 0.3M sucrose solution has the greatest amount of water molecules and the least amount of solute molecules. This occurs when there is a higher water potential in the sucrose solution and a lower water potential inside the root vegetable cells therefore this creates a bigger concentration gradient as

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work