Monthly Archives: February 2013

All are welcome here

As a general rule, I keep religion off bakingbiologist: it’s primarily a science blog, and I don’t want to alienate anybody who just came here looking for Molecular Biology 101 and tales about life as a grad student. But this made me smile. More churches need signs like this:

From a church in Builth Wells (in Wales).

Tales from the Teaching Lab: Early misconceptions in genetics

When I started this blog, it was supposed to be a news blog: me getting to grips with and explaining new papers that I found interesting. Recently I’ve been thoroughly uninspired, but trying not to resort to writing more opinion pieces about how to survive Grad school (even if that does seem to be what I do best).

Nevertheless, it’s been over 2 weeks since my last post, and while demonstrating yesterday, a familiar itch beginning to niggle. Whereas in previous years I’ve done a more-than-normal amount of tutoring and demonstrating, this year I’ve only covering a small handful of lab classes, one of which is Introductory Genetics. The class is pretty simple. Students are given a variety of mutant Arabidopsis that they have to phenotype, in addition to the F1 and F2 of back crosses to the wild type and crosses between mutants. They are trying to find out whether the mutations are single gene traits; dominants or recessive; and whether multiple mutants are caused by mutations in the same or different lines.

This is the third year I have demonstrated for this class, and the previous year I marked the open book exam that students take at the end, without having demonstrated for the practical, so I’m probably more familiar with the class than anybody except for the professor teaching it. Along the way I have had to do a fair amount of mental gymnastics, but I’ve also picked up on a few of the most common misconceptions that students hold. I actually clearly remember as a first year undergraduate being confused by the term “wild type” because nobody had explained to me that this was a technological term for the working copy of a gene: I thought it meant the type of gene that animals had in the wild. Which is fine, until you start thinking about mouse or Drosophila genetics!  Continue reading

Molecular Biology 101: DNA testing

Today, archaeologists from the University of Leicester announced that they believe they have found the lost grave of the last English King of the house of York, Richard III. They have been testing bones believed to be his to compare his DNA with that of known descendants in order to confirm his identity. This is a pretty similar process to the DNA testing we hear about all the time for paternity tests, or forensic studies: but how does it actually work? Continue reading