Pre-Assignment

1. How can the size of the molecules be determined from their migration distance on the finished gel?
2. Is there any direct relationship between the molar mass and the size of these dye molecules? Illustrate.
3. What was direction of electron flow through the gel?
4. Why should one not touch the gel while the electrophoresis was running?
5. Can one use an alternating current (A.C.) power supply source for gel electrophoresis? Why?
6. Why do the charged particles in a well move during electrophoresis run?
7. What are the effects of variations in the applied voltage on the gel electrophoresis?
8. What is the function of the comb?

Post-Assignment

1. Why does one see bubbles coming out in the electrode chambers?
2. Why had all the dyes not moved in the same direction through the gel?
3. Which of the dyes moved to the positive end of the gel?
4. What is the electrical charge adopted by Orange G under the experimental condition?
5. Which of the dyes were positively charged under the experimental condition?
6. Can one say which dye molecule has most likely the smallest size?
7. What would happen if one had placed the comb on the end/side slot of the casting tray?
8. If you wanted to run only DNA samples through the gel, where would you prefer to place the comb - on the middle or end slot of the tray and what should be the arrangement of the loading wells with respect to the electrodes?