Plant Organisation

• Difference between xylem and phloem: STRUCTURE 1) Xylem is made of dead cells, Phloem living 2) Both Tubular FUNCTION 1) xylem transports water, Phloem dissolved sugars. 2) Both transport substances through the stem.
• Phloem have pores to allow cell sap to flow through.
• Phloem - Translocation

  Xylem - Transpiration
• In the Phloem translocation goes both directions.
• Xylem are strengthened by lignin.
• Guard cells are adapted to open and close the stomata
• Guard cells have a kidney shape that open and close stomata.

  
  

  - Filled with water they turn turgid. Makes stoma open

  - Lack of water: they turn flaccid. Makes Stoma close

  - Sensitive to light: close at night