- Teaching Notes
- Supplemental Materials
Three Cases from the Membrane Files
The Exploding Fish, the Pleasurable Poison, and the Dangerous Diet
This PowerPoint-driven case study presents three different stories, each of which explores an aspect of membranes. The first (The Exploding Fish) covers diffusion, specifically addressing the question of why animal cells explode in freshwater but fish do not, and differences between saltwater and freshwater fish. The second case (The Pleasurable Poison) is designed to show that alcohol can slip across membranes and also highlights some of the problems of ingesting this toxin. The third case (The Dangerous Diet) explores a weight-loss drug, DNP, and how it operates in mitochondrial membranes. The first of these case studies also includes a number of "clicker" questions. These cases were originally designed for a semester-long, introductory biology course for non-majors, and instructors can choose to use one or all of the cases to suit their course.
|Keywords:||Membranes; mitochondria; semi-permeable; kidneys; alcohol; dinotrophenol; DNP; ATP; diffusion; osmosis|
|Educational Level:||High school, Undergraduate upper division|
|Subject Headings:||Biology (General) Cell Biology|
|Copyright:||Copyright held by the National Center for Case Study Teaching in Science, University at Buffalo, State University of New York. Please see our usage guidelines, which outline our policy concerning permissible reproduction of this work.|
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Optional PowerPoint presentation that can be used as preparatory material.Optional Pre-class Presentation
VideosThe following video(s) are recommended for use in association with this case study.
Diffusion Across Membranes
This four-second animation discusses two types of transport across cell membranes: active and passive transport. Running time: 0.04 min. Produced by HHMI BioInteractive.