4.4 Using Gel Electrophoresis to Study Molecules

Go to this link BioTech Gel, or http://biotech.emcp.net/gelelectrophoresis to learn how to analyze a DNA gel elctrophoresis. Follow the directions to conduct the "Virtual Lab". Write out the answers to the questions for submission.

1. Read through the background information on how to set up and run the gel simulation.

2. Then, in the simulation, "Choose a DNA to cut" choose pBR322 plasmid

a. What is the size of pBR322 in base pairs (bp)?

b. How many times is the plasmid cut by each of the following restriction enzymes?

ECO R1

Hinc II

Ple1

Bgl1

3. Choose the following for the restriction digestions:

Lane 1 - EcoR1 digest

Lane 2 - Hinc II digest

Lane 3 - Ple1 digest

Lane 4 - Bgl1 digest

4. Click the buttons to load each lane.

5. Click "Turn on the Power" let the gel run until the darker blue loading dye gets almost to the bottom of the gel.

6. Click " Turn OFF Power" and click "Turn on UV."

7. What are the sizes, in bp, of the molecular weight standards?

8. What are the sizes of the restriction enzyme-digested pieces of pBR322?

9. Add up the sizes of the fragments in each lane. What value does each lane's DNA come close to? Does this make sense? Why or why not?

10. Reset can be clicked to start the simulation over, if needed.