[Free Registration/Login may be required to access all resource tools.] The cell membrane is semi-permeable. Sometimes molecules need the help of special transport proteins or an input of energy to help them move across it. When an input...

Cell transport can be active or passive. The two forms are described here and their differences highlighted.

[Free Registration/Login may be required to access all resource tools.] Tutorial defines osmosis and the difference between osmosis and diffusion. Students will learn how to distinguish solute from solvent and solution and the hypotonic,...

[Free Registration/Login may be required to access all resource tools.] During active transport, molecules move from an area of low concentration to an area of high concentration. This is the opposite of diffusion, and these molecules...

Provides an overview of osmosis and tonicity and looks at how osmosis works, as well as the role it plays in the water balance of cells. Describes hypertonic, isotonic, and hypotonic solutions and their effect on cells.

A brief but clear explanation of passive and active transport. Examples are provided to further enhance clarity of the concepts.