Experiment- Do people have the same amount of salivary amylase?

Materials- (assuming the instructor has already completed steps 1 and 2)

        -well plate

        -distilled water (at least 50 ml)

        -pipette

        -starch solution (at least 7ml)

        -2 beakers (at least 50 ml each)

        -clock/timer

        -straw

        -stirring rod

        -10 ml graduated cylinder

        -saliva (at least 1 ml)

        - IKI2 (at least 10 drops)

        -test tube

Procedure-

1. Instructor) Prepare starch color guide by combining set amounts of starch and distilled water to create the following concentrations of starch. [2%, 1%, .5%, .25%, .125%, .0625%, and 0%] Then combine them with 10 drops of IKI2 in 6 separate wells of the well plate.
2. (Instructor) Prepare an initial starch solution with a starch to distilled water ratio of 2%. Provide enough for each student to complete the experiment.
3. Spit 1 ml of saliva through the straw into the graduated cylinder and add 9 ml of distilled water using the pipette. This dilution to 10% the previous concentration is necessary to lessen the amount of amylase that hydrolyses the starch in order to slow the reaction down far enough that it can be accurately observed.
4. Use the pipette to add 1 ml of the diluted saliva to the test tube. Rinse pipette with distilled water. Empty and rinse graduated cylinder with distilled water.
5. Use the pipette to add 7 ml of the starch to the graduated cylinder. Rinse the pipette with distilled water.
6. Pour the prepared 7 ml of the starch solution into the test tube and stir with the stirring rod. Begin timer. Rinse pipette with distilled water. Wait 15 minutes.
7. After 15 minutes, combine 6 drops of the saliva/starch, using the pipette, and 10 drops of IKI2, using the included dropper, in the well plate. This will result in a yellow liquid with a darkness based on the amount of starch left over from the hydrolysis.
8. Compare the resulting colored well to the wells of the previously prepared color guide to deduce the concentration of starch in your solution.
9. Record this information and share it with the class.

Analysis-

        Sum of students= 2+6+4+3=15

        Sum of Starch Concentration= 2(.5)+6(.25)+4(.125)+3(.0625)=3.1875

        Mean=µ= (Sum of Starch Concentration)/(Sum of Students)

                        Mean= 3.1875/15=.2125

        Range= (greatest starch concentration) – (least starch concentration)

                        Range= .5-.0625=.4375

        Median= .25

        Mode= .25

        Percentage of Students= (a selection)/(the whole)

                Ex.) Percentage of students with a resulting .5 concentration of starch= 2/15=13%

        Standard Deviation=σ= [A/ Sum of Starch Concentration]0.5

                        A= [data point- µ]2+[other data point- µ]2…+[other data point- µ]2

                Ex.) A= [.5-.2125]2+[.25-.2125]2+[.125-.2125]2+[.0625-.2125]2=.11421875

                Therefore σ= [.11421875/3.1875]0.5=.1892969449≈.189

Conclusion-

        Having completed this investigation I have concluded that my original hypothesis was correct in that different people do not have the same amount of salivary amylase. In fact, the standard deviation of the data is quite small showing that although every student in the sample did not share the same amount of amylase, they did have very similar amounts of salivary amylase. This would encourage the idea that all people have about the same amount of salivary amylase, but one must be careful to remember that there are outliers in the world that were not present in our small sample. However, the conclusions of this lab further support the evidence provided by the  and Dr. Stephen Gangemi of DrGangemi.com that proves that people do not have the same amount of salivary amylase. The procedure I followed could have been improved in several aspects. First, there were bubbles in the saliva that made measuring it out difficult. Though it would not have been practical, had we been given enough time for our lab, we could have tried to wait for the saliva to settle. Also the clock that was used to time the hydrolysis was not very accurate. The use of a simple stopwatch could have fixed this problem. The use of IKI2 as an indicator was extremely inaccurate. Perhaps come type of starch probe would have been able to more accurately indicate the concentration of starch. To perfect the lab we could have used some kind of amylase probe and directly measure the amount amylase in the saliva. Though there were many shortcomings to this investigation it was clear in showing that not all people have the same amount of amylase.