transpiration & translocation

• What are the two main mass transport systems in plants?

  Phloem and xylem
• What is the process of transporting sugars in plants called?

  Translocation
• Where does photosynthesis occur in plants?

  In the leaves
• How are phloem cells arranged to facilitate sugar transport?

  They are arranged end to end to form phloem tubes
• What do the small pores between phloem cells allow for?

  Movement of cell sap
• What is cell sap composed of?

  A liquid mixture of water and sugar
• What can sugars transported to other cells be used for?

  For energy or stored for later use
• In which directions can phloem transport substances?

  Up or down the plant
• What are xylem tubes made of?

  Dead xylem cells with no ends between them
• What is the role of xylem tubes?

  To transport water and mineral ions from the roots to the leaves
• What drives the movement of water through a plant?

  The evaporation of water from the leaves
• What is transpiration?

  The evaporation of water from the leaves
• What is the transpiration stream?

  The chain of water molecules moving up the plant
• What factors influence the rate of transpiration?

  Light intensity, temperature, air flow, and humidity
• How does light intensity affect transpiration?

  Higher light intensity increases photosynthesis and stomata opening, leading to more transpiration
• What happens to transpiration at nighttime?

  There is very little transpiration because stomata are closed
• How does temperature affect the rate of transpiration?

  Higher temperatures increase the rate of transpiration
• What is the effect of high airflow on transpiration?

  High airflow increases the rate of transpiration by maintaining a high concentration gradient
• How does humidity affect the rate of transpiration?

  Higher humidity decreases the rate of transpiration
• What are the key factors influencing the rate of transpiration?

  • Light intensity
  • Temperature
  • Air flow
  • Humidity
• Describe the differences between phloem and xylem in plants.

  Phloem:

  • Transports sugars (translocation)
  • Made of living cells arranged end to end
  • Can transport substances in both directions

  
  

  Xylem:

  • Transports water and minerals
  • Made of dead cells forming a hollow tube
  • Transports substances only upwards