Enzyme Controlled Reactions Lab Exercise 2 1 
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Virtual Lab: Enzyme Controlled Reactions
Instructions
1. Go to the following web-link in order to open the Virtual Lab:
http://www.mhhe.com/biosci/genbio/virtual_labs_2K8/labs/BL_02/index.html
2. Open the Virtual Lab: Enzyme Controlled Reactions
3. The virtual lab simulation will be on the right side of the screen, and the “Question” column will be on the left side of the screen.
4. Click the monitor in the lab simulation to watch a video about enzyme action.
5. Click the “Information” bar at the bottom of the lab simulation and read all the background information.
6. Read all background information and instructions in the “Question” column.
7. Answer questions 1-9 on the Enzyme Controlled Reactions Worksheet.
8. Follow the instructions in the “Question” column to complete the virtual lab. You must test each lactose sample at all pH levels: 3,5,7,9, and 11. Record your data in Table 1 on the Lab Worksheet.
9. Answer the question in the Lab Worksheet.
Virtual Lab: Enzyme Controlled Reactions Worksheet
1. Which of the following does NOT apply to an enzyme: B.
a. Catalyst
b. Inorganic
c. Protein
d. All of the above apply to an enzyme
2. When an enzyme catalyzes a reaction: A
a. Substrate(s) bind in the active site
b. Products bind in the active site
c. The shape of the enzyme remains unchanged
d. The enzyme is consumed by the reaction
3. Which of the following would interfere most with the ability of an enzyme to catalyze a reaction? A
a. Reduced concentration of substrate available
b. Reduced concentration of product available
c. Increased concentration of substrate available
d. A change in the pH
4. Feedback mechanisms regulate the rate of enzyme activity, effectively “turning off” an enzyme in a reversible way until more product is needed. Which of the following would be most effective as a feedback mechanism? D
a. Reduced concentration of product
b. Increased concentration of substrate
c. A change in pH
d. Temporary binding of a
Virtual Lab: Enzyme Controlled Reactions
Instructions
1. Go to the following web-link in order to open the Virtual Lab:
http://www.mhhe.com/biosci/genbio/virtual_labs_2K8/labs/BL_02/index.html
2. Open the Virtual Lab: Enzyme Controlled Reactions
3. The virtual lab simulation will be on the right side of the screen, and the “Question” column will be on the left side of the screen.
4. Click the monitor in the lab simulation to watch a video about enzyme action.
5. Click the “Information” bar at the bottom of the lab simulation and read all the background information.
6. Read all background information and instructions in the “Question” column.
7. Answer questions 1-9 on the Enzyme Controlled Reactions Worksheet.
8. Follow the instructions in the “Question” column to complete the virtual lab. You must test each lactose sample at all pH levels: 3,5,7,9, and 11. Record your data in Table 1 on the Lab Worksheet.
9. Answer the question in the Lab Worksheet.
Virtual Lab: Enzyme Controlled Reactions Worksheet
1. Which of the following does NOT apply to an enzyme: B.
a. Catalyst
b. Inorganic
c. Protein
d. All of the above apply to an enzyme
2. When an enzyme catalyzes a reaction: A
a. Substrate(s) bind in the active site
b. Products bind in the active site
c. The shape of the enzyme remains unchanged
d. The enzyme is consumed by the reaction
3. Which of the following would interfere most with the ability of an enzyme to catalyze a reaction? A
a. Reduced concentration of substrate available
b. Reduced concentration of product available
c. Increased concentration of substrate available
d. A change in the pH
4. Feedback mechanisms regulate the rate of enzyme activity, effectively “turning off” an enzyme in a reversible way until more product is needed. Which of the following would be most effective as a feedback mechanism? D
a. Reduced concentration of product
b. Increased concentration of substrate
c. A change in pH
d. Temporary binding of a