To Do

• Push flies
  

  Kathryn uses carbon dioxide to put the flies to sleep and then looks at them up close under the microscope. She has to look for specific mutations and compare the number of mutant and wildtype, or normal, flies to see if the fly cross, or mating of two flies, went correctly.
  Here she has crossed two carriers of the recessive ebony mutation so she expects 25% of the flies to have ebony colored bodies and 75% to have wildtype colored bodies. This Punnett square shows the cross:
  

  close

• Prepare DNA sample

  

  

  Kathryn now has to confirm that the flies she found have the mutated ebony gene. She prepares some of the ebony flies and extracts their DNA using a special solution. She then makes copies of the DNA using a polymerase chain reaction.

  close

• Run gel to look at DNA sample
  
  

  

  

  Now she uses gel electrophoresis to separate the DNA pieces by size.

  close

• Look at gel

  

  
  The DNA bands in the gel light up when exposed to UV light. This special box exposes the gel to UV light and takes a picture that she can save.

  

  
  In this room the UV light is not contained in a box so she to wear protective gear to protect herself from the damaging UV.
  It worked! The gel confirmed that the flies have the mutated ebony gene.

  close

• Analyze DNA results

   

  Kathryn sits down at the computer to analyze her results. She is able to see a list of nucleotides, or letters that make up the structure of the DNA in her sample.

  close

• Western blot to study proteins
  
  Western blots are used to look at proteins. Once the protein has been extracted and run through a gel, it is developed in a dark room like a photo.

  

  There is revolving door to the dark room to make sure light does get in and ruin the film.

  

  

  

  Now she can look at the developed film of the protein.

  close

• Make solutions

  

  

  
  While the lab does order some solutions, Kathryn makes a lot of solutions at her bench. All of these bottles are solutions she has made herself that she uses for different experiments.

  close

• Attend lab meeting

  

  

  

  Once a week all the scientists from the lab meet to share how their projects are going and to get help from each other. They do talk about their experiments with each other throughout the week, but these two hours are devoted exclusively to collaborating.

  close

• Update lab notebook

  

  
  Everything that she does in the lab is recorded in her notebooks. This is a critical step because she frequently reviews the work she has done in the past and because these notebooks are used as references for other scientists.

  close

• Consult list of phenotypes to design next cross.

Elizabeth Service
UNC Baccalaureate Education in Science and Teaching