Tag: permeable

  • Investigation: How Can Diffusion Be Observed?

    Investigation: How Can Diffusion Be Observed?

    This investigation provides a hands-on way to observe what happens when a chemical moves across a semipermeable membrane.   In this case, a cheap plastic bag serves as a model for the cell membrane and shows that iodine will move into the bag and turn the contents purple.

  • Investigation:  Observing Diffusion & Semi-Permeable Membranes

    Investigation: Observing Diffusion & Semi-Permeable Membranes

      Units on the cell will also include lessons about how the cell transports materials across the membrane.  For beginning biology students who don’t have a strong foundation in physical science, the ideas of entropy, solutions, and concentrations can be overwhelming.   Diffusion is easy to explain with a perfume bottle or food coloring.  …