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It's the Home Stretch

Mandy isolates DNA and shows us pictures!

I can’t believe there’s only about six weeks left to the semester. I’m almost half way through my career at Madison College. Only another three semesters left after this one! I remember being a little apprehensive about pursuing a degree and telling my dad “Holy Cow, maybe I’m too old to go back to school. I’ll be almost 40 before I’m a graduate.” And he replied “If you don’t go back, what will you be when you’re 40?” Do you think dads just sit around thinking up wise things to say?

This week in Cell Bio, we had an exam in lecture (groan) and then started in on the structure and replication of DNA. Rosalind Franklin, we know how awesome you really were. You go, girl.

In lab, my partner and I divided the work from two different experiments. In the first, we used restrictive enzymes (Hind III, Ban II and EcoRI) and electrophoresis to show the different banding patterns produced when bacterial DNA was cut at different sites by the restriction enzymes. At the top of the page, you can see our lab instructor, Adam, and my classmate, Scott, discussing the structure of DNA during this lab. And here’s our gel:


Pardon my photo of a photo


Next, we extracted the DNA from an onion by grinding it up with a morter and pestle (have I mentioned that much of the class was recuperating from a wicked cold when we decided to inundate the air with onion aerosols?), adding a homogenizing buffer and SDS, and setting it in a 60°C water bath for fifteen minutes.  Next, we moved the mixture to an ice bath to prevent the denaturation of the DNA and strained it through cheesecloth.  We then added ice cold ethanol and watched as our onion DNA popped into jellyfish-like visibility:


Hello, Beautiful.  I was hoping to see you here.


Biosafety ended this week with an exam (grooooooan) and we began Radioisotopes.  I have to admit, after the sheer, colossal volume of rote memorization involved with Cell Bio, it’s somewhat Zen to have a little breather in the form of some nice, predictable radioactive decay. 


Hope you had a happy Thanksgiving with full bellies and much good cheer!


(A note from the editor:  I posted this a little late and changed the tense to fit the date.)

Bio-Link Program: 
Madison Area Technical College


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