• The?roots,?stem?and?leaves?form a plant organ system for the transport of substances around the plant
• Plants also possess two specialist?transport vessels?called the?xylem?and?phloem
• The xylem and phloem are arranged throughout the root, stem and leaves in groups called?vascular bundles

Structure and function of the xylem

• Xylem vessels transport?water and minerals?(pronounced: zi-lem)?from the roots to the stem and leaves
• The xylem has some key?structural features
  • It is composed of?dead cells?which form?hollow tubes
  • Xylem cells are?strengthened by lignin?and so are adapted for the transport of water in the transpiration stream

   

Structure and function of the phloem

• Phloem vessels?transport food materials (mainly?sucrose and amino acids) made by the plant from photosynthesising leaves to non-photosynthesising regions in the roots and stem (pronounced: flow-em)
  • This means that movement can be in any direction around the plant

   

• The phloem has?structural features?different to the xylem
  • The cells are?living cells?and are not hollow
  • Substances move from cell to cell through?pores?in the end walls of each cell

   

The position of the xylem and phloem in the stem compared to the root