MOVEMENT OF WATER UP XYLEM

• MOVEMENT OF WATER UP THE XYLEM?

  1. Water vapour evaporates out stomata
  2. Loss in water volume = lower pressure
  3. When water is lost by transpiration, more pulled up the xylem to replace it
  4. Water molecules are cohesive (hydrogen bonds)
  5. Creates a column of water
  6. Water molecules adhere to xylem walls
  7. As column of water is pulled up xylem it creates tension
  8. Pulls xylem in to become narrower
• WHY IS WATER PULLED UP THE XYLEM TO REPLACE THE LOST WATER?

  negative pressure
• WHAT HAPPENS WHEN WATER MOLECULES ADHERE TO THE XYLEM WALLS?

  helps pull the column upwards