Movement of water through the root

• why must water move into the xylem?

  so that water can be distributed around the plant
• how can water travel through the plant?

  across the cells of the root cortex, by 3 different routes:

  • apoplast pathway
  • symplast pathway
  • vacuolar pathway
• what is the apoplast pathway?

  pathway of water through non-living spaces between cells and in cell walls outside the cell membrane
• what is the symplast pathway?

  pathway of water through plant, within cells in which molecules diffuse through the cytoplasm and plasmodesmata
• how does water move through the apoplast pathway?

  • water moves in the cell walls
  • cellulose fibres in the cell wall are separated by spaces through which the water moves
• how does water move through the symplast pathway?

  • water moves through the cytoplasm and plasmodesmata
  • plasmodesmata are strands of cytoplasm through pits in the cell wall joining adjacent cells so the symplast is a continual pathway across the root cortex
• how does water move through the vacuolar pathway?

  water moves from vacuole to vacuole
• what are the 2 main pathways that water moves through the root?

  • apoplast
  • symplast
• what pathway that water moves through the root is the fastest and most significant?

  the symplast pathway
• how does water move through the root?

  • theres a water potential gradient across the root cortex
  • it is highest in the root hair cells and lowest in the xylem so water moves down the water potential gradient, across the root
• what is this an image of?

  a diagram of the pathways of water transport across cortex