Chapter 5 Key Terms

  1. Cell Membranes (4)
    • Made up a phospholipid bilayer
    • Must be fluid to function properly
    • Switch from fluid to solid state as temperatures cool
    • Rich in unsaturated fatty acids
  2. Transport proteins
    Allow hydrophilic molecules to cross the membrane
  3. Diffusion
    Tendency for molecules to spread out evenly into an available space
  4. Concentration Gradient
    Determine the direction of diffusion, and this requires no work
  5. Osmosis
    Diffusion of water across a selectively permeable membrane
  6. Water Diffusion
    Diffuses across a membrane from the region of low concentration to the region of higher solute concentration
  7. Facilitated Diffusion
    Uses transport proteins to speed up the passive movement of molecules across the plasma membrane
  8. Transport Proteins
    Proteins, such as "Channel Proteins" and "Carrier Proteins" that are involved in facilitated diffusion
  9. Channel Proteins
    Provide a pore that allows a molecule to cross the membrane
  10. Carrier Proteins
    Proteins that undergo a change in shape to translocate solute-binding sites across the membrane
  11. Active Transport
    • Moves substances against their gradients and requires energy (ATP)
    • Allows cells to maintain concentration gradients that differ from their surroundings
  12. Membrane Potential
    The voltage difference across a membrane
  13. Voltage
    Created by differences in the distribution of positive and negative ions across a membrane
  14. Electrochemical gradient
    • Principle property that drives the diffusion of ions across a membrane
    • Determine by two forces: Chemical force and Electrical Force
  15. Electrogenic Pumps
    Transport proteins that generate voltage across a membrane and stores energy that can be used for cellular work
Card Set
Chapter 5 Key Terms
Key terms from chapter 5