Adaptations for transport in plants

• What is the function of vascular tissue in plants?

  Transports materials around the plant
• What are the two types of vascular tissue in plants?

  Xylem and phloem
• Where is xylem located in the roots?

  Central and star-shaped
• What is the arrangement of phloem in the roots?

  Between groups of xylem cells
• How does the arrangement of xylem and phloem in roots help the plant?

  Resists vertical stresses and anchors the plant
• How does the distribution of vascular tissue vary among plant species?

  It is affected by environmental factors
• What does xylem transport?

  Water and dissolved minerals
• What does phloem transport?

  Sugars produced during photosynthesis
• Where are vascular bundles located in stems?

  In a ring at the periphery
• What is the arrangement of xylem and phloem in stems?

  Xylem towards the center, phloem outside
• How does the arrangement of vascular bundles in stems benefit the plant?

  Provides flexible support and resists bending
• Where is vascular tissue found in leaves?

  In the midrib and network of veins
• What advantage does the vascular tissue arrangement in leaves provide?

  Gives flexible strength and resistance to tearing
• What is transpiration in plants?

  Water loss through evaporation
• Through which structures does transpiration mainly occur?

  Stomata and lenticels
• Where are stomata primarily located?

  On the underside of leaves
• How does transpiration create tension in the xylem?

  It pulls water from roots to leaves
• What factors affect the rate of transpiration?

  Light intensity, temperature, humidity, wind, water availability
• What is the flow of sugars in plants called?

  Translocation
• How does light intensity affect transpiration?

  Higher light intensity increases transpiration
• What effect does temperature have on transpiration?

  Higher temperature increases evaporation rate
• What is the maximum rate of translocation in plants?

  Up to 1m per hour
• How does humidity influence transpiration?

  High humidity reduces transpiration rate
• What is the effect of wind on transpiration?

  Windy conditions increase transpiration rate
• Why is the rate of translocation faster than diffusion?

  It involves active transport processes
• How does water availability affect transpiration?

  Well-watered plants have higher transpiration
• What does the pressure-flow hypothesis explain?

  How sugars move from sources to sinks
• What are xerophytes?

  Plants adapted to survive in dry conditions
• What is one adaptation of xerophytes to reduce water loss?

  Thick waxy cuticle
• What are the two main processes in the pressure-flow hypothesis?

  1. Loading: Sugars are actively transported into phloem.
  2. Unloading: Sugars move into the sink by active transport or facilitated diffusion.
• How do reduced leaves help xerophytes?

  Reduces surface area for transpiration
• What is the purpose of sunken stomata in xerophytes?

  To trap moist air
• What happens during the loading process in translocation?

  Sugars are actively transported into phloem
• How do hairs on leaves benefit xerophytes?

  They reduce transpiration
• How does loading affect the water potential of sieve tube elements?

  It reduces the water potential
• What role do water-storage tissues play in xerophytes?

  Store water during dry periods
• How do extensive root systems benefit xerophytes?

  Absorb as much water as possible
• What process moves water from the xylem to the phloem during loading?

  Osmosis
• What occurs during the unloading process in translocation?

  Sugars move from phloem to the sink
• How does unloading affect the water potential of sieve tube elements?

  It raises the water potential