Humpback Whale Pod Exploration

Name:

Period:

The Scenario:

For three years a team of researchers have been watching different Humpback whale pods off the coast of Hawaii. They are especially interested in the mating behaviors of these whales. As the number of humpback whales are decreasing, determining the genetic diversity of these populations is increasingly more important. In particular, this team is interested in finding out the father of one of the new baby whales, Luna. Through their observations of nursing behavior they have matched Luna with her mother, however, none of their observations have helped them link Luna to her father. Today you are going to help them figure this out!

Pod	Gender	DNA #
1	Female (Mother)	1
1	Female (Luna)	2
1	Male A	3
2	Male B	4

Some questions to get you thinking about today's lab:

What is DNA and what does it do?

What are some characteristics or properties of DNA?

How can we take advantage of these properties to help us figure out which whale is Luna's father?

What tricks can we use to see DNA?

Materials

• DNA from Mother (#1), Luna (#2), male whale A (#3), male whale B (#4).
• agarose
• Tris-acetate/EDTA solution (TAE)
• micropipette/tips
• electrophoresis apparatus and power supply

Procedure:

1. Get your electrophoresis apparatus. Make sure the comb is placed closest to the black electrode and that there are stoppers at both ends of the gel space.

2. Pour hot agarose into the gel space until it reaches the top of the gel box. Let the agarose harden, which should take about 10 minutes. Don't touch/move your gel until it's hard. Why not?

3. When the agarose gel is hard, take out the stoppers and gently remove the comb. Draw a picture of your gel and label which samples are where before you add DNA to the gel.
   
   
   
   
   
4. Load your DNA SAMPLES into the wells near the BLACK ELECTRODE. Why near the black electrode? Be sure to keep track of which samples you loaded in which lanes.
   
   
5. Pour the TAE solution into the side farthest from you samples, so that you gels is completely covered plus a little more. What do you think the TAE solution is for?

6. Run that gel!! Plug the electrodes into your gel box (red to red, black to black), being careful not to bump your gel too much. Plug the power source into an outlet and set to 100 V. How can you tell your gel is running?
   
   
   
   
   

   Analyzing Your DNA Data

   After about 30 minutes the DNA should be sufficiently separated to analyze, the purple dye has migrated approximately 2/3 of the gel, turn off the power and carefully remove the gel. The gel is very fragile, take care to not break it. You can remove the tray that you poured agarose on to and gently slide the gel into the staining tray. At this point you cannot see the DNA, what can you see and how do the four different lanes compare?

   Once you have placed your gel into the staining tray bring it to the staining station. Completely cover the gel with methylene blue and cover try with saran wrap. Stain overnight.

   Next day--Viewing the gel: Pour the methylene blue back into the bottle and carefully place the gel onto a white light box. The gel is very fragile so take care to not break it. Draw a picture of your stained gel, be as accurate as possible in drawing the bands:

   
   
   
   
   What can your data tell you about which whale is Luna's father?
   
   
   
   
   
   

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   BIOTECH Project Department of Molecular and Cellular Biology The University of Arizona September 18, 2000 Nadja Anderson, PhD Last Modified March 1, 2002 http://biotech.biology.arizona.edu