In this lab exercise, learners explore diffusion, cell membranes and particle size using beets and three alcohols. Generally, learners predict that smaller alcohols will permeate more quickly, and that higher concentrations will permeate more quickly than lower concentrations. As learners collect data, they will discover that their assumptions were wrong and begin to think critically about the nature of the composition of the membrane. This lesson guide includes data analysis questions for learners. The alcohols used in this lab are toxic and flammable; adult supervision and safety precautions recommended.