Transport in plants

• In xylem, the walls are made up of waterproof deposit called lignin, which provides mechanical support to the leaf.
• In xylem, the walls have no end walls which allow continuous of flow of water and mineral ions.
• Xylems are made up of dead cells.
• Phloem are made up of living cells.
• Phloem carries glucose and amino acids from the leaves to all parts of the plants.
• During transpiration, water potential in the cells decreases thus water is drawn from adjacent cells till it reaches the xylem vessels, causing a transpiration pull.
• Importance of transpiration:

  • Provides water to mesophyll cells for respiration.
  • Maintain a constant supply of ions and water to the leaves.
  • supply water to cells for metabolisms and for turgidity.