Factors Affecting Enzyme Activity
By: Anu Singh, period 4, Ms. Ferguson, Allen High School
In our experiment, we wanted to measure the effect of pH on enzyme activity.
Effect of pH on enzyme activity
What is the effect of pH on enzyme activity?
Prediction: If an enzyme reaches its optimal pH of 7, then it will have its optimal activity since it will be enough to lower activation energy, but not too much to denature it.
Null Hypothesis: pH has no effect on enzyme activity.
Alternative Hypothesis: Optimal pH of 7 determines the likelihood of increased enzyme activity.
Dependent Variable: Pressure
Constant: Amount of H2O2
amount of enzyme solution
Vernier Gas Pressure Sensor
10mL graduated cylinder
250mL of water
4 18x150mm test tubes
test tube rack
4 disposable pipettes
- Put 3 clean test tubes in a rack and label them pH4, pH7, and pH10.
- Add 3 mL of 3% H2O2 and 3mL of each pH buffer to each test tube
- In each tube add 2 drops of the enzyme solution
- Mix the substances in the tube and collect the pressure readings
- Remove and clean the tube
- Store Data
- Transfer data to excel and create and analyze data
- Repeat these steps for each pH
- Graph all three runs on one graph
Some errors that may have occurred were that the amount of pH added was not the precise amount, and the tubes may not have been properly cleaned, so they might have contaminated the hydrogen peroxide. To improve the experiment, we could do multiple trials of each pH to get more reliable data.
In the future, we can also test more pH values to find a more specific optimum pH.