Murder in main building: AP Biology students solve case


Blood. Vomit. Evidence markers—all the things you wouldn’t expect to find outside a high school classroom while walking down the main hallway. However, these were all part of an interactive AP Biology assignment that uses different reagents to discover the cause of a death. 

So, what is the context of the crime? 

“The whole idea of it is someone died; they ate something, [and] we have to make a decision between two restaurants,” Justin Choi (11) said. 

AP Biology students’ task was to determine which restaurant’s food killed the unidentified victim by testing to see how the vomit responded to Iodine, Sudan III and Bromine Sulfate, which are all reagents that react to different macromolecules .

“We would put the different reagents into test tubes, and then we would test to see which substance we found from the reagents,” Choi said. 

The color change in the reagent mixed with each sample of the victim’s vomit indicated which restaurant’s food led to the victim’s death. Sudan III and Bromine Sulfate resulted in little to no color change, but, when the vomit was tested with Iodine, the sample turned black.

“First we tested with iodine, and the vomit turned black,” Daniel Zhu (11) said. “That’s how we… found out that guy died from [eating carbohydrates].” 

There you have it: death by carbs.