Annika Midgarden
BIO 110 4:10-7:00
Lab Report
Introduction
Substrates and enzymes have a lot to do with each other. When substrates are brought together the chance of a chemical reaction occurring becomes higher. The substrate binds to the enzyme for a chemical reaction. CITATION Jea03 \l 1033 (Dickey, 2003). Enzymes are very particular about which substate binds to it; it has to be a specific one. (McGraw-Hill Education, 2013). In this experiment the enzyme is catecholase and the substrate is catechol and the catechol is being converted into benzoquinone. It is important to see the disappearance of the substrate (catechol) or the appearance of the product (benzoquinone) to measure how certain factor affect the particular enzyme, catecholase. CITATION Jea03 \l 1033 (Dickey, 2003).
In this experiment our hypothesis is that the more basic the pH substance is the more light it will absorb. We are predicting that the pH less that 7 or more acidic, is going to absorb more light that the pH above 7 or more basic. In this experiment the independent variable is the pH level and the dependent variable is the light absorbance. We chose this topic because we thought that it would be interesting to see what level of pH would absorb the most light and if our hypothesis would be correct or incorrect.
Materials and Methods
This experiment contains materials such as,1mL pipet, potato extract, pi-pump for 1mL pipet, wax marker, cleaning tissues, parafilm squares, 6 test tubes, a test tube rack, catechol, pH 2,4,7,8,10, distilled water and the Spectronic 20.
Once all the supplies are together it is time to start the experiment. First, get six clean test tubes and label them with the wax pencil 1 through 5 and on the sixth on label it B; the B is blank to set the absorbance reading to zero. Then get 1 mL of pH 2 and put it into test tube 1, 1mL pH 4 in test tube 2, 1 mL pH 7 in test tube 3, 1mL pH8 in test tube 4, and 1mL pH 10 in test tube 5. Take the B (blank) test tube and put 1mL of potato extract and 5 mL of distilled water in it. Cover it with a parafilm square to mix the two together. In each of the other test tubes put 2mL of caterchol in with the pH and 2mL of enzyme. Make sure to do the enzyme last in each test tube. Put a parafilm square over all of them and shake for 3 minutes. Use the blank tube to set the absorbency reading to zero. Then after 3 minutes take test tube 1 and wipe it off with a cleaning tissue and put the tube in the Spectronic 20 with the number facing forward. Observe the absorbency reading and record in table. Do the same steps for test tubes 2 through 5. After all data has been recorded do a second trial. Start at tube 1 measure and record the data. Do this again for test tube 2 through 5. Always use the blank test tube to set the absorbency reading to zero before putting each test tube in.
Results:
Table:
Tube pH level Absorbance Trial 1 Absorbance Trial 2 Average
1 2 0.285 0.3 0.292
2 4 0.38 0.42 0.4
3 7 0.564 0.576 0.57
4 8 0.572 0.578 0.575
5 10 0.27 0.279 0.274
The table is showing all the pH level and the absorbance level for each. It is also showing trial one, trail two and the average of both of them.
Graph:
This graph is showing the different pH levels and their average light absorbency that was recorded
Discussion
Our hypothesis was not completely supported by this experiment. Our hypothesis stated that the more basic the substance is the
