This minds-on, hands-on activity begins with an anchoring phenomenon, how a person’s breathing changes when he/she is re-breathing the air in a plastic bag. Students develop a negative feedback model of how the changes in breathing stabilize blood levels of O2 and CO2. To understand changes in breathing when running, students analyze cellular respiration.
Next, students use a negative feedback model to understand temperature regulation and homeostasis. Then, students analyze how failures of negative feedback can result in diabetes. Finally, students compare and contrast positive and negative feedback.
The Appendix for the Teacher Preparation Notes suggests an optional activity in which each student group investigates a question or hypothesis concerning negative feedback, homeostasis and changes in breathing.
Download Student Handout: PDF format or Word format
Download Teacher Preparation Notes: PDF format or Word format