Overall this experiment proved that substrate concentration decreased as time increased and eventually levels off when there is no more substrate to work on. Introduction: Catalane is an enzyme present in tissues. This potent enzyme converts H2O to water and oxygen. Catalane protects the body from accumulation of hydrogen peroxide since H2O is a waste product of many metabolic processes. Note that hydrogen peroxide naturally breaks up in the presence of sunlight, but like any enzyme, catalane lowers activation energy needed, therefore speeding the action.
This investigation will help prove the relationship, as time increases, substrate decreases. As the time periods increase, we should see a decline in the amount of Km needed to change the solution from white to brown. This means that less H2O is present. Catalane is especially abundant in liver cells of animals and other vertebrates, an organ that detoxifies many harmful substances, such as hydrogen peroxide. Hypothesis- If a beaker with 10 mil’s of catalane and 10 mil’s of H2O is left for 60 seconds then it will have less H2O left hen a beaker, containing the same materials, left for 10 seconds.
The beaker that was left for 60 seconds will have less substrate (H2O) because the reaction had more time to occur. As time increases, substrate concentration decreases. Materials: 1. 7 beakers (at least 50 ml_) 2. 70 mil’s of hydrogen peroxide 3. 60 mil’s of catalane 4. 70 mil’s of sulfuric acid 5. Potassium permanganate 6. Gloves 7. Lab coat 8. 3 pipettes (for catalane, Km, and sulfuric acid) 9. 10 mil’s distilled water 10. Timer Procedure: 1 . Label each beaker with the correct time interval from 10-60 seconds in ten second intervals (10, 20, 30, 40, 50, 60).
Label the remaining beaker “control”. 2. With the “control” beaker pour 10 mil’s of H2O, add 10 mil’s of distilled water (in place of the catalane). Finally add the 10 mil’s of sulfuric acid. 3. Suck up 10 mil’s of potassium permanganate in the pipette. Add potassium permanganate one drop at a time to the beaker. After each drop, stir the mixture. Continue to add Km to the mixture turns brown and stays brown. 4. Invert the pipette and record the amount of Km left in the pipette. Subtract the remaining amount from the starting amount (10 mil’s).
The answer is the amount of H2O left in the beaker. Record this amount. 5. In beaker 2 (10 seconds) add the 10 mil’s of H2O. Next add 10 mil’s of catalane. At the same time, press start on the timer. After 10 seconds add the sulfuric acid, to stop the reaction. Repeat step 3 and 4. 6. Repeat step 5, adding 10 seconds each beaker. Data: Table 1: Results of Enzymatic Reactions Control 10 sec. 20 sec. 30 sec. 40 sec. 50 sec. 60 sec. Amount of H2O 10 ml 8 ml 4 ml 2 ml . 2 ml . 1 ml Percent left 100% 10% 2% 1% Graph 1: Analysis: The goal was to find what effect time had on enzyme reaction.
By measuring the amount of Km after a certain time interval, we were able to record the amount of H2O after the reaction. The more potassium permanganate was needed to change the mixtures color, the more H2O was left. Referring to table one, you can observe the amount of H2O after each time period. Those amounts were then transferred to percentages based on the control group (0 seconds on graph 1). Conclusions: In conclusion, as time increases, substrate concentration, in this case the amount of hydrogen peroxide decreases. The data should have more f a steady decline, however, common error could have altered these results.
When repeating this experiment I will be sure to keep the H2O in the dark bottle to prevent it from breaking down due to the presence of sunlight. Leaving the hydrogen peroxide out interfered with the amount of enzymatic activity because it changed the starting amount of substrate. My hypothesis was correct in saying that there would be least H2O in the 60-second beaker. However, did not predict that there would be a shallower slope as time went on. Questions: To explore further in this experiment, I would first repeat this experiment adding more time for more accurate results.