I once (around 1974) took a course in Genetics and Embryology at a certain well-known New England prep school, and one of our lab experiments was the following :
We had to get some blood from our own fingertip (I never did get comfortable with this), centrifuge it (if I remember correctly), and then do a whole series of steps with various reagents, leading to ... having a wispy, strand of clumped, crystalline DNA (which should be stained orange, if I remember correctly).
Every student in the class (including me) had the procedure just not work at all. The teacher was very disappointed with us, and then, proceeded to do the whole thing himself, and it worked perfectly !
(This was the only "lab" where I totally "flubbed" it).
I have no idea why the teacher could get it to work, and none of us students could; but I was there, and saw it happen.
Jon. |
