If your population vial has enough adults, transfer them to a new vial; you'll count them on Tuesday. If you tranferred adults to a new vial last Thursday, remove them and count them today. If you have one newer vial with larvae, plus an older vial, clean out the disgusting old vial.
Work on your individual experiment
If you didn't take the color vision test four times last week, finish taking it.
I added 50 microliters of TE buffer (10 mM tris-HCl, ph 8.0, 1 mM EDTA) to each of the DNA preps you made last time. Today you'll run an aliquot from each one on a 1% minigel, then stain it with ethidium bromide and view it under UV light. If you get a nice looking band, it will indicate that you made lots of DNA. You won't need much DNA for PCR, so you might have enough DNA even if you don't see a band today, but it's still good to check.
Get your tube of DNA and look at it. Flick it a couple of times with your finger. You may see some swirling as the dense DNA solution mixes in with the rest of the buffer. Flick with your finger a few more times to mix it thoroughly. You don't want to mix DNA using a vortexer, because the DNA molecules can be physically damaged by violent shaking.
Spin the tube of DNA in the centrifuge for a few seconds. This will get the drops off the lid and down into the bottom of the tube.
Using a 10 microliter pipettor, remove 2 microliters of your DNA and add to a new microcentrifuge tube. Add 10 microliters of loading buffer (be sure to use a clean pipette tip!). Mix by flicking with your finger a few times, then spin for a few seconds in the microcentrifuge.
Go to the minigel I've got set up by the sink. Pipette 10 microliters of the DNA+loading buffer and load it into the first available well on the minigel. Record which lane you've loaded.
Once everyone has loaded the gel, we'll run it until the blue dye gets near the end. We'll then stain it and take a picture of the bands.
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This page was last revised November 6, 2008. Its URL is http://udel.edu/~mcdonald/geneticslab10.html