Case Study – Chicago Cyanide Murders

worksheet

This case focuses on a real event that happened in 1982 where several people were poisoned by taking Tylenol that had been laced with cyanide.  Students investigate how cyanide interferes with the mitochondria’s ability to create cellular energy.

Students follow the story of the seven seemingly unrelated victims of the poisoning. Then discusses symptoms of cyanide poisoning, such as dizziness, flushed skin tone, and shortness of breath. Students suggest how they would proceed with an investigation. Autopsy reveals that the victims dies of hypoxia and had mitochondrial damage.

Students then discuss how the damage to mitochondria is related to death by hypoxia. They must wrestle with the idea that even though the oxygen levels in the blood were high, death was caused by lack of oxygen. This is a good place to review the role of the mitochondria in cellular respiration.

The worksheet includes a detailed model of the mitochondrion showing the electron transport chain and how cyanide interferes with the last protein in the chain, cytochrome c.   Students will color the model to understand how the electron transport chain works. Ultimately, the chain stops because of the damage to cytochrome c. Therefore, oxygen that is available in the blood goes unused by the mitochondria. The activity also provides students with an answer to the question of why we need oxygen and oxygen’s important role in cellular respiration.

Teachers can print the document and/or use a Slide presentation to create a more instructor-led activity.  The activity was designed for AP Biology students but can be used with basic biology if the instructor provides additional guidance.

Grade Level:  9-12 | Time Required 1 hr

HS-LS1-7 Use a model to illustrate that cellular respiration is a chemical process whereby the bonds of food molecules and oxygen molecules are broken and the bonds in new compounds are formed resulting in a net transfer of energy.

Related Resources

Murder Mystery Macromolecule Lab – examine the contents of a stomach to determine the last thing a victim ate

How Does Mitochondria Produce Energy for the Cell – color the mitochondria and the equation for cellular respiration

What Causes Mitochondrial Disease – explores mutations related to mitochondria protein complexes