Transport in plants

• What are the components of the vascular bundle in roots?

  Xylem and phloem
• What is the function of the vascular bundle?

  Transport substances and provide structural support
• How are xylem vessels arranged in the vascular bundle?

  In an X shape
• Why is the X shape arrangement of xylem vessels important?

  It helps withstand mechanical forces
• What surrounds the X shape arrangement of xylem vessels?

  Endodermis
• What is the role of the endodermis in the vascular bundle?

  Supplies xylem vessels with water
• What is the inner layer of meristem cells in the vascular bundle called?

  Pericycle
• Where is xylem located in non-woody plants?

  On the inside of the vascular bundle
• What is the position of phloem in the vascular bundle?

  Found on the outside of the vascular bundle
• What is the layer of cambium responsible for?

  Production of new xylem and phloem tissue
• What do vascular bundles form in a leaf?

  The midrib and veins
• How do dicotyledonous leaves differ in vein structure?

  They have a network of veins
• What do xylem vessels transport?

  Water and minerals
• What structural feature allows xylem vessels to form a continuous column?

  They are long cylinders with open ends
• What do pits in xylem vessels enable?

  Sideways movement of water
• What substance thickens xylem vessels?

  Lignin
• How is lignin deposited in xylem vessels?

  In spiral patterns
• In which direction can water flow in xylem vessels?

  Only upwards
• What are phloem vessels made of?

  Living cells
• What is the function of phloem vessels?

  Involved in translocation of nutrients
• What do sieve tube elements transport?

  Sugars such as sucrose
• How do companion cells assist sieve tube elements?

  By producing ATP for active processes
• What are plasmodesmata?

  Gaps allowing communication between cells
• What is transpiration?

  Process of water absorption and release
• What enters and exits through a leaf's stomata?

  Carbon dioxide enters, water and oxygen exit
• What does the transpiration stream enable in plants?

  Photosynthesis, growth, and elongation
• How does transpiration help control plant temperature?

  Through evaporation of water
• What process involves water moving from xylem to mesophyll cells?

  Osmosis
• What happens during evaporation in transpiration?

  Water vapor moves from mesophyll cells
• What drives the diffusion of water vapor out of the stomata?

  A water vapor potential gradient
• What tool can be used to investigate the rate of transpiration?

  Potometer
• How does a potometer measure transpiration rate?

  By measuring movement of the meniscus
• What factors affect the rate of transpiration?

  Leaves, stomata, light, temperature, humidity
• How does the presence of a waxy cuticle affect transpiration?

  It reduces water loss from leaves
• How does air movement influence transpiration rate?

  Increased air movement enhances transpiration
• How does humidity affect the rate of transpiration?

  Higher humidity decreases transpiration rate
• How does light affect the rate of transpiration?

  More light increases transpiration rate
• How does water availability influence transpiration?

  Low water availability decreases transpiration