rate of enzyme-catalyzed reactions

Explain how environmental factors affect the rate of enzyme-catalyzed reaction. Explain why catalysis activity decreased over time. 3. Introduction • An enzyme is a specific organic catalyst (substance that speeds up reaction without being used up in the experiment) in which it binds on to a specific substrate (reactant) at the active site and lowers the activation energy required to perform that reaction. Enzymes are important biologically because, for example, the human body performs certain reactions that keep us alive and most of them react at 37 degrees Celsius (body temperature.

In each of these reactions, there is an enzyme that catalyzes these reactions to lower the amount of energy needed to perform this reaction. If enzymes didn’t exist then body temperature wouldn’t be enough to perform any of these reactions properly. Enzymes have certain conditions in which it will work in. For instance, most enzymes react at certain temperatures (varies in each enzyme), most enzymes react from a pH of 6- 8, and react faster or slower according to the amount of substrate present.

Altering temperature, pH level, and concentrations of enzyme and substrates may cause absolute no change to the activation energy in which the enzyme would have been denatured. In addition to these environmental factors, other molecules may react with an enzyme. These may have great to no effect on the enzymes. Those that increase the rate of substrate entrance into the active site are known as activators by hitting the enzyme on one side of the protein (enzymes are protein) and altering the shape of the active site on the other side.

Those molecules that slow down or stop activation are known as inhibitors which bind on to one side of the protein and cause the active site to misshapen which would decrease or eliminate the amount of substrates that may enter the active site. 4. Materials and Methods • See lab notebook pages. 5. Results 2a: 1. Observe the reaction a. What is the enzyme in this reaction? • Catalase solution b. What is the substrate in this reaction? • H2O2 c. What is the product in this reaction? • H20 and 02 d. How could you show that the gas evolved is 02 Capture bubbles in closed solution and ignite. If flame appears then if 02 2. Explain the reason for this difference. • First reaction had 02 gas bubbles and the second one did not have bubbles. 3. What do you observe? What do you think would happen if the liver was boiled before being added to the H2O2? • Gaseous bubbles formed around the liver. If liver had been boiled there would be no bubbles. 2b: Baseline calculation Final reading of burette 22. 5 mL Initial reading of burette 26. 5 mL Baseline (initial- final) 4 mL 2c: Uncatalyzed H2O2 decomposition

Explain your prediction. a. Lowering the temperature slow the rate of enzyme activity because of the effect on the activation energy. 6. Design a controlled experiment to test the effect of varying pH, temperature, or enzyme concentration. a. A controlled experiment that would test pH could include comparing two groups, a control group with no added acid, and an experimental group with added acid. Each group would consist of a solution containing an enzyme such as catalase and the material it breaks down such as H2O2.

The independent variable would be the added acid while the dependent variable would be the difference in amount of H2O2 broken down. This could be measured through a titration of KMnO4. Discussion: Experimental results in 2D did not support conclusion effectively. Conclusion should’ve reflected that when time is a factor, more and more substrate gets used up by the enzyme. The reason is because when the titration was taking place, different people were doing it which would affect the credibility and precision of the titration. This false procedure caused the results to vary and fluctuate accordingly to the mistake taking place.