plant trasnport

• Autotrophic


  Plants make their own food
• Photosynthesis


  The process by which plants make their own food
• Plant Transport System


  • Provides the materials needed for various plant metabolic processes, including photosynthesis, respiration, growth, and reproduction
• Materials transported in plants

  • Water
  • Minerals
  • Carbon Dioxide
  • Oxygen
  • Carbohydrates produced in photosynthesis
  • Growth Regulators

  
• Functions of Water in a Plant

  Used in chemical reactions, excellent solvent, medium for reactions to take place, maintains cell turgidity
• Water Uptake


  1. Water enters root hair cells by osmosis

  2. Root hairs are adapted for this process

  3. Water moves by diffusion from root hairs into ground tissue

  4. Reaches the xylem

  
• Transpiration


  The loss of water vapour from the surface of the leaves

  
• Path of water


  Soil → root hairs → ground tissue (by diffusion) → xylem

  
• Control of Transpiration in leaves

  • Presence or absence of a cuticle
  • Opening and closing of the stomata

  
• Environmental Factors Affecting Transpiration

  • Bright sun increases photosynthesis and water needed
  • High temperature increases evaporation and transpiration
  • Windy conditions increase water loss and transpiration
  • Water shortage causes wilting and stomata closing
• Mineral Transport


  1. Minerals enter root hairs dissolved in water by active transport

  2. Transported in xylem tissue

  
• Carbon Dioxide


  Absorbed from atmosphere through stomata or obtained from respiration in leaf cells

  
• Oxygen


  Formed by photosynthesis, may diffuse out through stomata or be used by leaf cells for respiration

  
• Glucose


  Formed in photosynthesis, may be used directly in respiration, stored as starch, or transported as sucrose in phloem

  
• Maple syrup is the sugary sap from a maple tree, collected and boiled
• Food Storage Organs in Plants

  • Modified Root (Carrot)
  • Modified Stem (Potato)
  • Modified Leaf (Onion)
• Modified Roots


  • Parsnip
  • Turnip
• Modified Stems


  • Asparagus
• Modified Leaves


  • Cabbage
  • Lettuce
• Gas Exchange in Plants

  • Takes place in the leaves
  • Carbon dioxide diffuses in through stomata, oxygen and water diffuse out
• Adaptations in the leaf for gas exchange

  • Large number of stomata
  • Large surface area
  • Thin organ
  • Presence of air spaces
• Stomata


  • Stay open during the day for photosynthesis and water loss
  • Can stay closed at night when no light for photosynthesis
• Stomata opening and closing

  • Guard cells swell with water to open
  • Guard cells lose water to close
• Gas Exchange in Stems

  • Thick epidermis/bark does not permit gas passage
  • Lenticels are openings in bark that allow oxygen in and carbon dioxide/water vapour out