Transport Systems in Animals and Plants


  • Main carriageway for transporting water through the plant
  • It is made of specialised xylem tissue
  • Water enters the root system via osmosis


  • Phloem is the vessel that transports products of photosynthesis via active transport
  • Phloem consists of two types of living cells:
    • Companion cells
      • Smaller cells found along the side of the sieve tube cells
      • Contain nucleus, mitochondria, vacuoles and other cell organelles
      • Control the activities of sieve tube cells
    • Sieve tube cells
      • Long and thin with large pores through the cell wall at either end
      • No nuclei, mitochondria or vacuole
      • Arranged end to end in sieve tubes