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teaching

Easy DNA extractions (with pineapple!)

First wet lab work I've done in more than a month. Also how often do you see a bottle actually LABELLED as "Strawberry DNA extraction"?

It’s actually quite easy* to extract visible quantities of DNA from fruits and vegetables using nothing less common than dish soap and rubbing alcohol. For our class we chose strawberries, but I also heard of people using kiwis and bananas to great success.

Of course it takes a mere second for someone to say “I don’t eat food with genes in it” and 15 minutes to prove them wrong by extracting DNA from an (organically grown) banana, but that imbalance between the time and effort it takes to repeat piece of false information and the time it takes to refute that same misinformation isn’t going to change. It is something anyone in the habit of going up against misconceptions with nothing but demonstrable facts on their side has to get used to.

The demonstration itself went pretty smoothly. Unfortunately, since it’s a hundred student lecture, we had to do most of the preparation beforehand, so I don’t think most of them realized just how easy DNA extractions can be.

*Note that this recipe calls for the use of meat tenderizer to break down some of the remaining proteins in the solution before extracting DNA, and points out that pineapple juice will make an acceptable alternative (as it also contains enzymes that break down proteins.) I mention this only to reiterate my point, as if you hadn’t heard it before, that pineapples are one of the most awesome fruits known to mankind.

My First Day Teaching (prologue)

Random photo of the blooming zebra plant (of the Aphelandra sqarrosa variety) in my office. Because I've been writing too many picture-less posts lately,

I don’t actually start for another two and a half hours. But at 2 pm pacific time I’m going to assume the role of a graduate student instructor (Berkeley’s fancy name for a TA) in the first of the two discussion sections I’ll be teaching every week.

As first classes to TA go, this one feels like a good fit for me. It is an introductory course in plant biology aimed at non-science majors. A couple of the people in my year did this for the first time last semester with courses on plant biochemistry or computational biology and spent the whole time trying to keep one week ahead of their students in learning the material. In a course on introductory plant biology and agricultural/biotech issues we’re going to be discussing stuff I know and am excited about!

The professor who gives the lectures seems pretty awesome too. In a semester she’s planning to cover everything from basic biology cell cycle and DNA->RNA->protein to plant specific biology like floral development and plant pathogens, and at the same time get the students thinking and writing about their views on biotechnology, agriculture, and biofuels.

It should make for an exciting semester.

Also, lectures are in an auditorium with over 100 seats and at the first one, on Tuesday, every single one was taken and there were people sitting in the aisles. At Cornell the only plant biology class I ever took that even approached that kind of enrollment was the two weeks I took of Intro Botany. Great to see so many people excited about plants and their molecular biology (or at least willing to sit through a semester of lectures and discussion sections on the subject to fulfil some distribution requirement)!