DnA Lab (Lab 4A,B,I,J)
Purpose: To learn how to make solutions and use them to analyze DNA particles.
Materials:
Balance (Analytic and Tabletop)
Weigh Paper/ Boats Scoop Sodium Chloride Tubes TRIS EDTA Ethanol (95%) 600 mL Beakers 125 mL Bottle
100 mL Graduated Cylinder PH strips Hydrochloric Acid Sodium Hydroxide Glass Stirring Rods 50 mL Beakers DNA (Salmon Sperm) 2 mL Pipet Agarose
Microwave Oven Gloves to protect hands Safety Goggles Gel Box Power Supply Mini Centrifuge Ethidium Bromide Micro-pipette Tips |
Procedure:
Lab 4A
Part I: 1. Measure out 2.92 g of NaCl and place it in a tube 2. QS water to 10 mL 3. Label container Part II: 1. Add 0.1576 g of TRIS and 0.037224 g of EDTA to the beaker 2. Add 80 mL of deionized water to beaker 3. Add HCl to raise pH or NaOH to lower pH until the pH of the solution is between 7.5 and 8.5 4. QS water to 100 mL 5. Label container Lab 4B
1. Add 1 mL DNA and 1 mL TE to a beaker. 2. Add 5M NaCl to the solution 3. Add 4 mL ETOH by pouring down side (forms two layers) 4. Using a glass stirring rod, spool the DNA from the solution. 5. Place DNA in a tube with 2 mL TE Lab 4I
1. Add 0.4 g agarose powder and QS TAE to 100 mL 2. Heat solution until agarose is dissolved. 3. Let solution cool and then pour into gel box with the combs inserted Lab 4J
1. Submerge gel and electrodes in the TAE 2. Add 20 uL DNA and 4 mL of 6x loading dye into a tube 3. Centrifuge the solution to mix it 4. Load solution into wells in the gel 5. Hook the power source to gel for about 40 minutes 6. Stain with Ethidium Bromide and record observations. |
Here is a picture of the results of the electrophoresis:
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Data Analysis:
At first, our results did not turn out well at all - the stain did not show us any DNA. We came up with a few hypotheses about why this happened, but since this happened for all the groups in both classes, the most likely cause of the problem was that the stain was bad. So, we re-stained the gels and you can see the results of that on the right.
Conclusion:
This lab was successful in teaching the class a few lab techniques, like using the balances. We also got some hands on experience with the DNA - such as spooling it, and mixing it into other solutions. These techniques can be used to identify people by their DNA, and maybe even identify the criminal at a crime scene.
Reflection:
I think my group worked nicely together ... until a few more people were added to our group, which greatly decreased our productivity. Most of the work in the lab was done by two people, while everyone else just stood there watching. Next time, I would prefer if we could just stay in a small group instead. Overall, I found this lab very interesting and fun.
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