loss of water via evaporation from the aerial parts of a plant
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
osmosis
the movement of water across membranes in response to differences in water potential
cohesion vs adhesion
hydrogen bonding causes both in the xylem
cohesion - water molecules with each other
adhesion - water molecules with cell walls
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
3 routes through root cortex to zylem
1. transmembrane route - water channels located in the plasma membranes of root cells