Lab 3 in Cafeteria Caper was an examination of hair samples from the 5 suspects and the evidence recovered from the scene of the "crime". One of the suspects had black hair, one red and three had bleached blonde hair.
The detectives learned to make wet prep slides and hair scale casts. I learned a lot about hair myself. The FBI site had some good info on basic structure of hair, identifying human and animal hair. I did wet preps and scale casts of Jasper and Krunk's hair to illustrate the difference to the young detectives.
The hair samples were provided by a mom, a detective and a beautician friend of the mom. It was clear that the black hair did not match the evidence which was light in color. The red hair sample was very pale and did not show the difference in the placement of pigment granules toward the medulla, rather than toward the cortex, as seen in other hair colors. The bleached blonde hair of suspects 2, 3 and 4 matched the evidence. The samples did not show the damage to the cortex that one would expect in bleached hair.
Next week will be our last lab. We will do the Lesson 4, Blood, Chromosomes and DNA Analysis. This will be a good review of Punnett squares and other things we studied last fall. Then we will have an end of lab lunch party here at our house. I hope the weather is warm enough to sit outside. PRM