Cell Membrane. Cell Membrane (Lipid Bilayer, Plasma Membrane) Function – Regulates what enters and leaves the cell and also provides protection and support.

Cell Membrane

Cell Membrane (Lipid Bilayer, Plasma Membrane)

•Function – Regulates what enters and leaves the cell and also provides protection and support.

Cell Membrane (Lipid Bilayer, Plasma Membrane)

•Structure – A double layered sheet. Gives the cell membrane a tough, flexible structure.

Cell Membrane (Lipid Bilayer, Plasma Membrane)

•Selectively Permeable – Allows only certain substances to pass through.

Passive Transport

• Movement of molecules across a membrane that does NOT require energy.

Passive Transport

• Diffusion – Movement of molecules from an area of high concentration to an area of low concentration.

Passive Transport

• Osmosis – Diffusion of water.

Active Transport

• Movement of molecules across a membrane that DOES require energy.