transpiration and translocation

• Xylem vessels have thick cell walls made up of lignin which makes them strong enough to support the weight of water against gravity.
• phloem transports what?

  food substances, mainly dissolved sugars
• what do plants do with food substances transported?


  used immediately/stored
• what types of cell are phloem tubes made from?

  elongated living cells with small pores to allow cell sap to flow through
• which direction does translocation happen in in phloem?

  both directions
• what is process of transport of food in phloem called?

  translocation
• xylem tubes are made of dead cells and are hollow to allow water to flow through.
• xylem tubes are strengthened with lignin
• xylem tubes carry water and mineral ions from the roots to the stem and leaves
• the movement of water from the roots, through the xylem and out of the leaves is called the transpiration stream
• xylem tubes take water up
• transpiration is the loss of water from a plant
• what is transpiration caused by?

  evaporation and diffusion of water from a plants surface
• most transpiration happens at the leaves