Understanding Movement of Molecules across the Cell Membrane

This lesson uses a macro-model to demonstrate the diffusion of molecules across the cell membrane.  A deshelled egg serves as the cell model to observe movement in and out of the “cell”.  Students will learn that the cell membrane is composed of a complex nano-structured membrane that regulates diffusion and mobility of membrane biomolecules. The purpose is to examine permeability properties of plasma membranes and give students a better understanding of how substances, nano in size move into and out of a cell.