Osmosis: In or Out?

 

Tested Studies in Laboratory Teaching, 2013, Volume 34

Tamara Sluss

Abstract

This introductory biology laboratory activity explored osmosis with solutions of unknown concentration using materials from a grocery store. In this lab, a raw egg minus the shell, served as the model cell, and was weighed then placed either in water, a sports drink, or corn syrup for 30 to forty-five minutes. Students calculated the average differences between the final and initial egg mass for each medium: water, sports drink, or corn syrup to determine whether the "cell" is hypertonic, hypotonic, or isotonic to the surrounding solution. While osmosis takes place, the instructor had ample time to cover background information of osmosis in order for students to be able to make conclusions based on their results.

Keywords:  osmosis, measurement

University of North Carolina, Chapel Hill (2012)