Bio 220 - Chapter 5 Membrane Dynamics

  1. Some transport processes use transport proteins in the plasma membrane, but do not require ATP. This type of transport is known as...
    Facilitated diffusion
  2. The majority of water molecules moving across plasma membranes by osmosis do so via a process that is most similar to...
    Facilitated diffusion
  3. The sodium-postassium pump uses ATP to move sodium and postassium ions across the plasma membrane.  This statement describes...
    primary active transport
  4. A vesicle fuses with the plasma membrane and releases its contents to the extracellular fluid.  This statement describes...
  5. A water filled passage that allows small molecules to pass through the membrane
    channel proteins
  6. transports larger molecules by binding to the protein
    carrier proteins
  7. Active transport of molecules require ATP because 
    the molecules are moved against their concentration gradients (uphill)
  8. The tonicity of a solution depends ONLY upon the...
    concentration of nonpenetrating solutes
  9. The membrane potential of most cells
    is negative, except when there is a change in the membrane permeability to ions
  10. Which body fluid compartment contains high levels of K+, large anions, and proteins?
    intracellular fluid
  11. which body fluid compartment contains higher levels of Na+, Cl-, and HCO3-?
    plasma and interstitial fluid
  12. bulk flow is fluid flow as a result of a ___ gradient.
    pressure gradient
  13. what are the two extracellular fluid compartments in the body?
    • plasma
    • interstitial
  14. The ion that plays a key role in initiating electrical signals in neurons is
  15. passive transport refers to a process that requires
    no cellular energy
  16. Na+ ions are more concentrated in the extracellular fluid than in the intracellular fluid. This is an example of
    chemical disequilibrium
  17. The inside of a resting cell is slightly negative relative to the outside.  This is an example of
    electrical disequilibrium
  18. Water will always move from ___ areas to ___ areas.
    HYPOsmotic to HYPERosmotic
  19. membranes are selectively
  20. permeability is determined by
    • size
    • charge
    • lipid solubility
    • also: carriers & channels
  21. rate of diffusion is proportional to:
    Surface area X concentration gradient X permeability

    divided by: membrane thickness
    Fick's Law
  22. movement of molecules from a region of high concentration to a region of low concentration due to the kinetic energy inherent in the molecules
  23. diffusion that does not require input of energy
    passive diffusion
  24. rate of diffusion is affected by:
    • concentration gradient
    • distance
    • temperature
    • molecular weight
  25. proteins embedded in the membrane that move molecules from one side to the other
    mediated transport
  26. two types of transport proteins?
    • channels
    • carriers
  27. water filled tubes that allow specific molecules to pass
    channel transport proteins (open or gated)
  28. a transport protein that binds to the molecule then changes shape to carry it 
    carrier transport protein
  29. two types of cotransport proteins
    • symport
    • antiport
  30. a cotransporter that carries two molecules in the same direction
  31. a cotransporter that carries two molecules in opposite directions (NaK pump)
  32. transport channels that remain open
    leak channels
  33. passive transport is also called
    facilitated diffusion
  34. molecules moving against the concentration gradient and requires energy
    active transport
  35. active transport requires
  36. two types of active transport
    • Primary active transport
    • Secondary active transport
  37. Transport when ATP is directly activating a protein
    Primary active transport
  38. Transport that uses the energy of a concentration gradient to pump another ion (not Na+) out of the cell
    secondary active transport
  39. the interaction between the protein transporter and its ligand is specific
  40. molecules that have similar structure will compete with each other for binding to the transport protein
  41. the transport protein can only accomodate so many molecules at a time - reaches max rate
  42. movement of a large molecule, whole organisms, or damaged cells
    vesicular transport
  43. a type of endocytosis that creates a tunnel through a cell
    potocytosis "caveolae"
  44. moving molecules out of cells, mostly proteins
  45. moving molecules in to cells
  46. the Na+K+pump is a type of _____ transport
    primary active transport
  47. molarity is calculated by
    molecular weight in grams/1 L
  48. osmolarity is the 
    molarity x number of particles per molecule

    example: NaCl is 2 particles
  49. two solutions have the same osmolarity
  50. this solution has fewer dissolved particles than the other
  51. this solution has more dissolved particles than the other
  52. the number of particles in a solution
  53. Compares the inside of the cell to the fluid outside the cell
  54. this type of solute is not factored when considering tonicity
    Penetrating solutes (PS)
  55. water does not move into or out of the cell
  56. water will leave the cell
    cell shrinks
  57. water will enter the cell
    cell will swell
  58. charge distribution that creates disequilibrium is from the activity of
  59. the separation of charges at unequal distribution across a membrane results in
    electrical disequilibrium
  60. the difference between the outside and the inside of membranes mades the membrane
  61. if the difference in charge of the membrane increases it becomes
  62. if the difference in charge of the membrane decreases it becomes
Card Set
Bio 220 - Chapter 5 Membrane Dynamics
Bio 220 - Chapter 5 - Membrane Dynamics