Working with High Schoolers

Hello there,

During the first week of June a high school AP Biology class from Bruton High School came into the lab to finish an experiment that I developed.  One of my projects last year was to create a high school lab protocol using fruit flies that would hopefully get high school students more excited about biology than previous high school labs.  Much of high school lab protocols using fruit flies simply teach students about the passage of visible traits like eye color and wing shape from one generation to the next through use of Punnett squares. However, the kind of things we do in our lab are much more interesting and complex than simply tracking physical traits using Mendelian principles.

My lab deals with switching the sex of fruit flies using RNAi constructs.  When a female specific transcription factor is degraded using RNAi, this causes their somatic sex to change to male while their germline sex remains females.  Germline stem cells give rise to sperm in testis and eggs in ovaries.  Thus, in this case flies that would normally develop into females instead look male on the outside even though they still should develop ovaries like a normal female.

Before the students came into the lab, I gave them a number of vials in which I had already set up different matings between virgin females and males of a different genotype.  In their class, the students put those flies to sleep that hatched from that mating over the course of a week, and analyzed their gender under a dissecting microscope.  After counting the number of males and females they saw based on visible features, they attempted to confirm what they observed through use of Punnett squares to predict how many females should have their sex switched. That part of the lab was like other high school lab protocols because they used Punnett squares and Mendelian principles to track how many flies would stay normal or change sex based on the genotype of the flies in the mating I set up.

Next they brought their fruit flies into our lab so they could dissect out their ovaries and testes.  Later they looked at those ovaries and testis under our confocal microscope to determine if there were any abnormalities and to see if visibly male flies actually had ovaries instead of testes.  Confocoal microscopes are not readily available for high schools to use because they are very expense and would be little use to anyone outside of a research lab.  What’s so cool about them is that they allow for 3D imaging of the samples on our slides.

It seemed like the students who came in really enjoyed seeing what a professional research lab was like and learning about the different techniques we use in our lab to study stem cell development in fruit fly gonads.  Hopefully getting hands on experience in a professional research lab utilizing current technology and studying concepts that are being studied by real scientists was rewarding for them.  This experience was also like a beta testing for the lab protocol I made, so I found some things I could improve upon and to make clearer.  Also, the plan is that students will do more of the procedures in their classroom.  I plan on making some videos as demonstrations for portions of the lab.

 

Comments

  1. I am a big fan of your methods in this AP Biology class. I took many chemistry classes in high school, including AP Chemistry, and for the most part, I felt like the classes themselves were not as interactive as they should have been. It’s one thing to read about a topic, but for a lot of students, it clicks more easily when they are being hands-on and interactive. I’m glad it was successful for both you and your students.

  2. resullivan says:

    I did the original AP Bio lad that you’re working to correct, and your version is clearly better. Many of the people in the class with me were thinking about going into biological research of some sort, and a lab like yours is definitely much better preparation for that, instead of just writing out Punnett Squares. I’m quite jealous of the class that got to take part.