I use this introductory exercise at the beginning (the very first thing) of my one semester topics course in Bioinorganic Chemistry and as the first exercise in my Bioinorganic unit in my senior level Inorganic Course. The exercise is a very simple one, but generates a lot of great discussion, requiring students to access knowledge from prior chemistry and biology courses, as well s common knowledge from sources external to their academic career. Students are often surprised to see how much they know before a topic is covered.
I distribute to each student a photocopied periodic table along with 3 different highlighter pens.
I then ask the following three questions, giving the students 5 minutes for each. Students are instructed to highlight only a section of each box (element).
Q1. Identify all the metals that are required in biological systems.
Q2. Identify all the metals that are toxic to biological systems.
Q3. Identify the metals that are used for medicinal purposes.
• A student should be able to identify (some) metals that are required in biological systems.
• A student should be able to identify (some) metals that are toxic to biological systems.
• A student should be able to identify (some) metals that are used for medicinal purposes.
• A student should be able to discuss the factors that determine whether a metal is toxic or not, including oxidation states, quantities, etc.
Periodic Tables, highlighter pens
I use periodic tables created by Todd Helmenstine and maintained at http://chemistry.about.com