BIO 153 P4

loss of water via evaporation from the aerial parts of a plant

the potential energy that water has in a particular environment compared with the potential energy of pure water at room temperature and atmospheric pressure

the movement of water across membranes in response to differences in water potential

• hydrogen bonding causes both in the xylem
• cohesion - water molecules with each other
• adhesion - water molecules with cell walls

• 1. root pressure - pressure potential in the roots
• 2. capillary action
• 3. cohesion-tension

• 1. transmembrane route - water channels located in the plasma membranes of root cells
• 2. apoplastic - outside the plasma membrane
• 2. symplastic - via plasmodesmata

the movement of sugars throughout a plant

sieve-tube members and companion cells