Structure Function Activity Plasma Membrane Structure Function Activity

Plasma Membrane Phospholipids Membrane proteins Fluid Mosaic Model Basic molecular component of membrane Must be fluid Membrane proteins Fluid Mosaic Model

Plasma Membrane Phospholipid bilayer Formed by association of hydrophobic tails Polar (hydrophillic) groups form inside and outside of membrane

Plasma Membrane Membrane Proteins Proteins are integral or peripheral Proteins involved in plasma membrane functions

Plasma Membrane Fluid Mosaic Model Membrane must be fluid to function Components are free (to a degree) to move across surface

Plasma Membrane Functions Boundary between inside and outside Recognition Energy (respiration and photosynthesis) Selective permeability of materials Diffusion Active transport Bulk transport

Plasma Membrane

Plasma Membrane Diffusion Processes Simple Diffusion – movement of small uncharged molecules Osmosis – special case of diffusion; diffusion of water in response to solute concentration Facilitated Diffusion – diffusion using a channel protein

Plasma Membrane Diffusion – the movement of molecules from area of high concentration to low concentration

Plasma Membrane Osmosis Isotonic Solute concentration same on both sides of plasma membrane

Plasma Membrane Hypotonic Hypo- below Solute concentration less outside cell than inside cell

Plasma Membrane Hypertonic Hyper- above Solute concentration greater outside cell than inside

Plasma Membrane Facilitated Diffusion Diffusion that occurs through use of a channel protein

Plasma Membrane Active Transport Movement against energy concentration gradient Requires energy; usually in form of ATP

Plasma Membrane Bulk transport Eukaryotic cells only Endocytosis Pinocytosis Phagocytosis Exocytosis & secretory processes