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Research Question
Do the catalase from different organism have different reaction rates? -
Period: to
Potato Catalase Experiment
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Background Research:
Enzymes are catalysts that catalyzes or speeds up chemical reactions
Catalase is a type of enzyme.
Yeast & potatoes both have catalase.
When an enzyme catalyzes a reaction, it binds to a substrate, undergoes a physical change that modifies the substrate, then releases the modified substrate as the product.
(Freeman, 2011). -
Hypothesis:
If catalase from different organism are used, the reaction rates will differ. -
Experiment:
We will test our hypothesis by conducting a catalase assay (2-8), for the positive control, negative control, and our experimental variable. -
Materials:
Yeast; Saccharomyces cerevisiae (Positive Control)
Water (Negative Control)
Potato (Experimental Variable)
Hydrogen Peroxide (H202)
DI Water
Erlenmeyer Flask
Blender
25 mL graduated cylinder -
Protocol:
The catalase enzyme in yeast catalyzes the chemical reaction and reduces H202 to water and oxygen.
We will measure water displacement and convert it to mmols displaced for our data.
Conversion: water displaced mmols
(xx ml)(4.46 mmols/100 ml)= xxx mmols displaced
Data collected: Time (sec.) vs. mmols of Water Displaced
(Casem, 2011). -
Rationale
By doing the catalase assay, we’re using the water displacement method to measure oxygen (02) production created by the catalase in yeast and potato. -
Controls/Reagants:
Positive Control: 10% Yeast concentration; Saccharomyces cerevisiae
Negative Control: Water
Experimental Variable: 10%, 20%, & 50% Potato concentrations To make 10% potato concentrations, we blended 10 grams of potato with 90 ml of DI water.
20% potato concentration= 20 g potato + 80 ml DI water
50% potato concentration= 50 g potato + 50 ml DI water -
Sample Size:
Yeast (Positive Control) Replicates: 4 (1 per day)
Water (Negative Control) Replicates: 4
(1 per day)
Potato (Experimental Variable) Replicates:
10 % Conc. – 13
20% Conc. – 2
50% Conc.- 3 -
Discussion:
No significant difference was seen between samples with pure potato vs. potato with its peel.
On Day 4, we increased our potato concentration to 50% to see if any drastic changes occurred. There was a noticeable reaction rate increase, but still not comparable to that of yeast. -
Data/Results
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Conclusion:
Catalase from different organisms (yeast and potato) had different velocities or reaction rates.
Yeast catalase produced the most oxygen and had the highest reaction rate.
The velocity of catalase in yeast was a lot faster than the reaction velocity of the potato.
1 ml yeast had more catalase than 1 ml of potato. -
Hypothesis is True!
