Yeast Production of Catalase
By: Blayne Childers, Luke Wimmer, and Lindsey Wimmer
Problem
Hypothesis
Manipulated Variable
The Control Experiment
Three Constant Factors
2. The amount of yeast catalase (1 teaspoon)
3. The amount of solutions mixed (20 mL of each solution)
Materials
yeast catalase
graduated cylinder
small beaker
test tubes
filter paper discs
forceps
water bath
stop watch or timer
20 mL of hydrogen peroxide (pH of 5)
20 mL of vinegar (2.4) - Acidic
20 mL of bleach (12.6) - Basic
pH paper
wax marking pencil
Procedure
1. Pour 20 mL H2O2, vinegar, and bleach (separately) into a 25 mL graduated cylinder (or a tall cup with mm markings)
2. Pick up 1 filter paper disc with forceps
3. Soak the filter paper disc in catalase solution for 5 seconds and then air dry
4. Drop disc into graduated cylinder and start stopwatch as soon as the disc hits the surface of the H2O2
5. Stop the stop watch when the disc reaches the top of the liquid in the graduated cylinder
6. Measure the total distance in mm the disc travels
Note: use the mL markings as if they were mm
Note: for some of the trials, the disc may not reach the bottom of the cylinder!
Note: total distance is distance the disc travels down and back up!
7. Record the time in seconds
8. Calculate rate as mm/s
(Note: the disc traveled 20 mL down and then 20 mL back up to the surface!)
9. Repeat 3—5 times and calculate average rate and range