Electron Transport Chain

Introduction/Background: In Jennifer Osterhage's Introductory Biology I taught at the University of Kentucky, she taught the concepts involved in the electron transport chain using a fun, interactive activity with clickers and student volunteers.  

 

Goal/s: The goals of this activity are to understand the electron transport chain and the effect of perturbations on the system.

Class: BIO148: Introductory Biology I

Procedure:

 

  1. First, students must listen to a mini-lecture about cellular respiration.
  2. The activity takes place in two parts:
    1. Students looked at data from "autopsies" from the tylenol murders in 1982 (adapted from Buffalo case study). Clicker questions asked what was the direct target of the poison in the tylenol. Was glycolysis the direct target, etc?
    2. After a discussion that the target must be part of the electron transport chain (ETC), the instructor asked student volunteers to come up and act as members of the chain. Tennis balls were electrons. Electrons were passed from NADH and FADH2 to members of the complex.
  3. When the first electrons reached cytochrome c, the instructor used a rope (threw it around the student) to illustrate the mechanism of cyanide.
  4. Students discuss how 02 levels would be normal but NADH elevated if cyanide present - answer clicker questions.

 

Follow-up: Formative assessment built into the activity with clicker questions throughout. There was a quiz over the material the next class.

Comments: Students liked analyzing the autopsy data and like being able to visualize the ETC by acting it out.

Materials/Resources: Clickers; student volunteers held sheets to act as members of the electron transport chain