Introduction and Objective
In Mr. Wong’s 7th period biology honors class, we did a lab experiment involving the exothermic reaction between the enzyme catalase and hydrogen peroxide. The objective of this experiment was to measure the difference in product oxygen from the previously stated reaction. There were filter paper dots soaked in catalase and immersed in hydrogen peroxide inside of a reaction chamber. The chamber was placed underwater and the bubbles of oxygen were collected in a graduated cylinder. The amount was measured and the results were analyzed.
Experiment Question
How will the number of dots soaked in catalase affect the amount of oxygen that comes out of this experiment? Is there a pattern to the change in the amount of produced oxygen?
Hypothesis
If the number of dots increases, the amount of catalase will increase; therefore, it will increase the amount of oxygen outputted from the reaction chamber. The results will show that the lined up graphs will have different average lines.
Materials
- Safety goggles
- 50 mL lab beakers
- 10 mL and 50 mL graduated cylinders
- Fresh 3% Hydrogen Peroxide
- Bucket of water
- Catalase solution
- Punched out pieces of filter paper
- Reaction chamber (with one-hole stoppers)
- Hole stopper
- Stop watch
Procedure
- Clean all containers thoroughly
- Measure all the required fluids carefully
- Soak 10 filter paper disks in catalase and let them sit
- Conduct the actual experiment
- Take one of the disks and stick it to the wall of the reaction chamber.
- Add 10 mL of hydrogen peroxide to the bottom of the reaction chamber and make sure it does not touch the disk.
- Stopper the chamber with the stopper and a glass straw.
- Fill one of Mr. Wong’s white tubs 2/3 of the way full with water.
- Submerge a graduated cylinder in water and remove all air from it.
- Turn it over so it is sticking out of the water upside-down but is still filled with water (do not allow the mouth of the cylinder to come out of the water
- Put the reaction chamber into the water, placing the glass straw’s opening under the graduated cylinder.
- Flip the reaction chamber 180° so that the H2O2 comes into contact with the disk.
- Measure the volume of the oxygen every 30 seconds.
- Repeat all the sub-steps in Step 4 putting 2 disks into the chamber instead of one.
- Repeat all the sub-steps in Step 4 putting 3 disks into the chamber instead of one.
- Repeat all the sub-steps in Step 4 putting 4 disks into the chamber instead of one.
- Record all of the data into the chart in Mr. Wong’s worksheet.
Results
The results provided information that the number of catalase molecules available to react with hydrogen peroxide affected the reaction speed.
The results showed that the volume of the gas increased as the disks increased in number.
| M | I | N | U | T | E | S | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| # of disks | 0 | 0.5 | 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 |
| 1 | 0 | 0.4 | 0.8 | 1.2 | 1.4 | 1.6 | 1.8 | 2 | 2.4 | 2.6 | 2.8 |
| 2 | 0 | 1 | 2 | 2.8 | 3.2 | 3.5 | 3.9 | 4.2 | 4.7 | 5.1 | 5.4 |
| 3 | 0 | 0.5 | 1 | 2 | 2.5 | 3.5 | 4.5 | 5 | 6 | 6.5 | 7 |
| 4 | 0 | 1.5 | 2.6 | 3.8 | 4.5 | 5.2 | 6 | 7 | 7.5 | 8 |
Analysis
- Does the action of the catalase change through time? Explain your answer.
- Yes, the action of the enzyme catalase changes over times. I created linear graphs in addition to the segmented statistics graph. The slope of the lines increases, which means that the speed of the reaction increases exponentially to an extent. If the action of the catalase was the same, the lines would have the same slopes. They would be the same but with higher statistics. If the difference was additive, then the lines would all be parallel.
- Based on these data, how does enzyme activity vary with concentration?
- Because the disks were all soaked in the same amount of catalase, the speed of the reaction increased. In other words, The number of machines that break down hydrogen peroxide was increased, and the amount of hydrogen peroxide was kept constant. That means the process is faster. However, if there are too many enzymes, they may “compete” for the right to break down substrate and the process will slow down. In the results, that point was no reached because the line was not vertical. When the line becomes vertical, then it has reached the limit for quickness of reaction. In my results, I found that the one with the most dots started lower than the others but sped up faster. So, it is proven by the results that the amount of contact and the amount of enzymes affect this experiment greatly by decreasing and then sharply increasing the results.
- Based on these data, how does substrate concentration affect enzyme action?
- There will be more collisions of enzymes and substrate molecules. Then, the reaction will occur faster. The enzymes will speed up because there will be more substrate molecules colliding with them and it is easier to find something to react with.
- Based on these data, how does temperature affect enzyme action?
- When enzymes are heated, the act faster, but if they are heated too much, they will become denatured enzymes. They will not work if they become denatured. (We did not do this part of the experiment in class)
- Summarize the general conditions necessary for effective enzyme action. Are these conditions the same for each enzyme? Why or why not?
- There must be a standard temperature, maximum surface area, enough enzyme, and enough substrate. Each has a delicate part in the functionality of an enzyme. Each enzyme must have its specified conditions unless the experiment is to kill the enzymes. Each enzyme is slightly different, but they all need about the same conditions to function and survive.
Conclusion
In conclusion, this experiment was successful. The hypothesis was correct. All of the trials with more than one disk was visibly greater than the trial with one disk. All of the trials went smoothly and the data was recorded well. The entire experiment taught me about reaction systems. There are enzymes that react with a substrate. The speed can be increased by increasing the amount of enzyme, the amount of substrate, or the temperature. However, all of these have their limitations. they all need to be within a certain amount limit. If there are too many or too few, the reaction of the enzyme will not function. Clearly, this experiment was one of much learning.
mattbiowong 