Download CH- 7.3 Cell Membrane

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.