Purpose: the purpose of the experiment was to test an enzymes ability to catalyze. We saw the relationship between the amount of enzymes in a solution and the ability of the enzyme to catalyze. The rate of which the enzyme catalyzes was what we were testing and the time that we left the solution catalyzing was the variable.
Introduction: certain enzymes increase the reaction rate of certain solutions by lowering the activation energy. Certain substrates bind to the enzyme at the activation site. The enzyme lowers the activation energy and this speeds up the reaction. The reaction will continue to occur until all of the substrate is used up due to the fact that enzymes never get used up. Enzymes are proteins so they are affected the same ways as proteins. Proteins can be denatured when the pH or temperature of the solution is affected. Once a protein is denatured the function will no longer be carried out so the enzyme will never catalyze.
Methods: we began with 10 mL of H2O2 in each cup. We began the reaction by adding in 1mL of yeast that had enzymes that catalyzed with H2O2. We timed each reaction and once time ended we added in 10 mL of H2SO4 to stop the reaction. We did this with each time. Once we did this we took a 5 mL sample and titrated KMnO4 into the solution until in turned purple. We started with a baseline test that did not undergo a reaction. Then we moved on to the other cups. The KMnO4 reacted with the H2O2 until all of it was gone. This meant that the our baseline number minus the amount of KMnO4 added to the solution was the amount of H2O2 used up in the reaction. We recorded and then continued to the next cup.
Data:
Graphs:
Discussion: We wanted to know how fast the enzyme could catalyze the reaction. The titration of the solution measured this and we found that the longer the reaction was allowed to work the less substrate was left. This is due in part to the enzyme working to lower activation energy and speed up the reaction. Also the optimal pH for the enzyme is very close to neutral. By adding an acid we denatured the protein which is what stopped the reaction from proceeding at its catalyze do speed and due to this the enzymes couldn't lower activation energy. We are unsure why we have an outliers in our data. For the most part the end result of our experiment (time 360 seconds) was what we were expecting but the in between didn't quite match up with what we were expecting. Our numbers increased until 60 seconds then it decreased until 120 seconds then it increased again. Besides these intervals of three data points the data fit what we were trying to understand. The longer that an enzyme is left in a solution the less substrate there will be.
Conclusion: the longer an enzyme is left in a solution with substrate the less substrate there will be. The enzyme will never be used up so the reaction will continue going. For the most part we saw this in our experiment. The amount of substrate continually decreased except for at two points.
