Transport in Plants

• Xylem + Phloem

  • Vascular tissue
  • Located together in vascular bundles (in roots, stems and leaves)
  • Pericycle:
  • Parenchyma tissue
  • Inside root
  • Under endodermis surrounding vascular tissue
  • Endodermis:
  • Specialised cell
  • Surrounding central vascular tissue in root with
  • Waterproof suberin layer in cell walls
  • Stele:
  • Vascular tissue + pericycle + endodermis
  • Cambium:
  • Meristematic tissue layer between xylem and phloem
  • Cortex:
  • Parenchyma tissue layer
  • Surround stele in roots
  • Epidermis:
  • Outer flattened cell layer
  • Specialised with root hairs, increase SA
  • For water uptake
• Plant Transport

  • Cells need:
  • CO_2
  • Oxygen
  • Organic molecules
  • Inorganic ions
  • Water; gases not transported around plant
  • Multicellular
  • Should have low SA:V
  • Branching shape inc
  • Low metabolic rate
  • Can survive w/ slower transport system + no pump
  • Both systems move by mass flow; bulk transport from high to low pressure
  • Tissue types:
  • Parenchyma:
  • Simple living cells
  • Thin cellulose cell walls
  • Collenchyma:
  • Simple living cells
  • Some irregular lignin thickening, corners
  • Supporting tissue
  • Sclerenchyma:
  • Dead cells
  • Thick lignified cell walls
  • Fibre bundles
  • Dicotyledon:
  • Flowering
  • Large broad leaves
  • Branching veins
  • Monocotyledon:
  • Flowering
  • Long thin leaves
  • Parallel veins