Transport in Plants

• Why do multicellular organisms need transport systems?

  • Cells need various substances to live (e.g., water, minerals, sugars)
  • Waste substances need to be removed
  • Direct diffusion is too slow for large distances
• How do unicellular organisms transport substances?

  By diffusion directly across the cell membrane
• What are the two main transport systems in plants?

  Xylem and phloem
• What is the function of xylem tubes in plants?

  • Transport water and minerals
  • Carry substances from the roots up the shoot to the leaves and other parts
• What is the function of phloem tubes in plants?

  • Transport sugars from the leaves to other parts of the plant
  • This process is known as translocation
• How do root hairs increase water absorption?

  • Grow into long "hairs" that stick out into the soil
  • Cover each branch of a root with millions of microscopic hairs
  • Increase surface area for absorption
• What is translocation in plants?

  • The movement of food substances around the plant
  • Primarily involves the transport of sugars from leaves to other parts