Transport in the xylem

• What is the Casparian strip made out of?

  Suberin, which makes it hydrophobic
• What are the 3 different pathways that water can take through the root?

  Apoplast pathway

  Symplast pathway

  Vacuolar pathway
• What is the apoplast pathway?

  water moves IN the cell walls. Cellulose fibres in the cell wall are separated by spaces through which water moves
• What is the symplast pathway?

  Water moves in the cytoplasm and plasmodesmata.
• What is the vacuolar pathway?

  Water moves from vacuole to vacuole
• Describe and explain the role of the endodermis in the uptake of water into the xylem?

  The endodermis contains the Casparian strip, which is made of suberin, which is hydrophobic. This means water cannot travel in the cell walls, so it must move into the symplast pathway.
• Label this diagram with the parts of the root and the different pathways ater can take.

  A) xylem

  B) pericycle

  C) endodermis

  D) casparian strip

  E) cortex

  F) epidermis

  G) apoplast pathway

  H) symplast pathway