Lab: Enzymes Essay
Answer the questions and report your data in this fillable PDF using the observations and results you recorded in your lab manual while performing the experiments. Save the completed PDF file with your last name and lab number and submit the report as directed by your instructor. (For example: jones_lab5.pdf)
Consider the Concepts
1. If a chemical reaction is exergonic, it is considered spontaneous. Explain in one to two complete sentences why a spontaneous reaction would benefit from an enzyme to catalyze the reaction. A enzyme helps to slow down the amount of energy required to start a reaction. One of the other benefits is helping to regulate the metabolic pathway to help with the enzyme formation.
Part 1: Effect of Enzyme Concentration
2. What were the independent and dependent variables in this experiment? Independent variable
The independent variable is the equal amount of hydrogen peroxide .
Dependent variable The inflation of the balloon being measured by various yeast concentrates. 3. Name three variables that you controlled between conditions in this experiment.
1. The same amount of time was given to each reaction.
2. A balloon was used to measure all three experiments.
3. All three were given the same amount of hydrogen peroxide.
4. Using the data you recorded in the lab manual, calculate the RATE of the reaction catalyzed by catalase. To calculate rate, divide the final balloon circumference (units: centimeters) by the total time the reaction was allowed to occur (units: seconds). Complete the following table with the reaction rate as the production of gas per second (units: cm/sec).
5. Using the results of your experiment, describe the relationship between the amount of enzyme added to the reaction and the amount of oxygen gas produced. Even though the yeast concentrates were all different the reaction times were all very similar. All three produced almost the same amount of oxygen. The lowest concentrate did not produce as much oxygen it still produced an impressive result.
Part 2: Effect of Temperature on Enzyme Activity
6. What were the independent and dependent variables in this experiment?
The independent variable is the amount of oxygen produced.
The inflation of the balloon being measured by various temperatures.
7. Complete the following table with the RATE of your enzyme-catalyzed reactions and the temperature of the substrate at the time the reaction STARTED. Instructions for calculating the rate of reaction are provided in Question #4 above.
8. Based on your data alone, describe the relationship between the temperature of the reaction and the amount of oxygen gas produced.
Based on the data it showed that both hot and cold water created quicker chemical responses than the room temperature water. It also showed that both hot and cold water created relatively close measures of reaction.
9. From your data alone, can you draw conclusions about the expected rate of the enzyme reaction in temperatures other than those you tested? Why or why not? The conclusion I can draw from this experiment is that in a heated environment you will create a higher concentrate of enzyme reaction. You can also conclude that in a cold environment it will still trigger similar enzyme results. Room temperature will still bring results but on a slower lesser concentrate.
10. The experiment you performed was designed for a student to perform the lab at home, with consideration for both time and lab kit supplies. If you were a scientist in a laboratory, describe at least two specific things you would improve about the experimental design that would allow your new results to directly evaluate a hypothesis about the optimal temperature for catalase in yeast. I would try larger amounts of product in both hotter and cooler environments. I would also take longer segments at measuring the response times to see a specific time signature of the reactants.
Part 3: Enzymes in Food
11. What is the substrate of the chemical reaction catalyzed by amylase?
Amylase is the substrate that helps to separate starch and sugar concentrates from foods.
12. What substance were you trying to deposit onto the paper towel when you rubbed food onto it? Iodine
13. What occurred during the five-minute wait after rubbing food onto the
The foods juices were either merging or separating form the with the starch.
14. Considering what you know about amylase and your experimental results, write a hypothesis about what taste and texture characteristics you would expect to find in a fruit or vegetable with large amounts of amylase. It may help to review the rules for a good hypothesis before answering this question.
The taste and texture of fruit and vegetables with large amounts of amylase would be very sweet as amylase in our saliva begins to break down the foods into sugars. I would propose that some fruits to have higher concentrates of sugar and easier to break down.
15. Write a prediction based upon your hypothesis about about how much amylase you would expect to find in a banana.
I would expect to find some traces of sugar in bananas that would require more amylase from our saliva.
16. Paste up to four photos of you with your completed lab experiments as directed by your instructor. For this lab, your instructor may have directed you to include a photo (or saved screen shot) of one or more graphs you created using your experimental data.