BIO 153 P4

  1. transpiration
    loss of water via evaporation from the aerial parts of a plant
  2. water potential
    the potential energy that water has in a particular environment compared with the potential energy of pure water at room temperature and atmospheric pressure
  3. osmosis
    the movement of water across membranes in response to differences in water potential
  4. cohesion vs adhesion
    • hydrogen bonding causes both in the xylem
    • cohesion - water molecules with each other
    • adhesion - water molecules with cell walls
  5. What causes water to travel up the stem against gravity and exit the leaves?
    • 1. root pressure - pressure potential in the roots
    • 2. capillary action
    • 3. cohesion-tension
  6. 3 routes through root cortex to zylem
    • 1. transmembrane route - water channels located in the plasma membranes of root cells
    • 2. apoplastic - outside the plasma membrane
    • 2. symplastic - via plasmodesmata
  7. translocation
    the movement of sugars throughout a plant
  8. the anatomy of phloem
    sieve-tube members and companion cells
Card Set
BIO 153 P4