Plant transport system

• How does water enter root hair cell?


  The cell sap in the root hair cell is a relatively concentrated solution of sugars and various

  mineral salts. Thus, the sap has a lower water potential

  than the soil solution. Water enters the

  root hair cell via osmosis.
• Adaption of root hair cells

  Long narrow protrusion to increase SA to V ratio and increase rate of osmosis or diffusion of dissolved mineral salts
• How do root hair cells continuously absorb water via osmosis?

  Root hair cells will absorb dissolved mineral salts from the soil via active transport. This causes the root hair cells to lower their water potential, compared to that of the soil solution. Water molecules then enter the root hair cells via osmosis.
• Xylem characteristic and functions


  • Have a hollow lumen and walls strengthened by lignin deposits

  Functions:

  
  

  • Transports water and dissolved mineral salts from roots to stem and leaves

  • Provides mechanical support for plant
• Phloem functions


  Transports sucrose and amino acids from leaves to other parts of the plant.

  • Glucose produced during photosynthesis is

  converted into sucrose before being transported in the phloem.
• Sieve plates


  Facilitates flow of substances through phloem cells
• Why must a plant cell be turgid?

  To provide mechanical support to the plant