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13 Cards in this Set

  • Front
  • Back
the outer boundary of cells
plasma membrane
made up of 2 layers of molecules called teh phospholipids
lipid bilayer
random movement of ions and other particles
greater concentration to less
dynamic equilibrum
no energy required
passive transport
diffusion of water in and out of cells across a selectively permeable membrane
use of transport proteins to aid the passage of particles across the plasma membrane
facilitated difusion
provides water-filled passages through which small dissolved particles like ions can diffuse
channel proteins
change shape to allow certain molecules to cross the plasma membrane
carrier protein
open to allow plassage of particles, when a "signal" molecule combines with the gate. when the signal molecule is released, the gate closes.
gate protein
lesser concentration to greater concentration

energy required
active transport
process whic the plama membrane engulfs and takes in substances from a cell's environment
takes out substances from a cell's environment