paper two

• Photosynthesis


  1. Take water

  2. Take carbon dioxide

  3. Turn into oxygen

  4. Turn into glucose
• The photosynthesis equation needs to be balanced
• The balanced photosynthesis equation is 6H2O + 6CO2 → 6O2 + C6H12O6
• In photosynthesis, energy is taken from light
• Photosynthesis is an endothermic reaction
• Requirements for photosynthesis


  • Chlorophyll
  • Water
  • Carbon dioxide
  • Sunlight
• As the percentage level of carbon dioxide increases

  The rate of photosynthesis increases
• As temperature increases


  The rate of photosynthesis increases
• As temperature gets too high

  The rate of photosynthesis decreases due to enzyme denaturation
• As light intensity increases

  The rate of photosynthesis increases
• Even when the photosynthesis graph is flat, there is still a steady rate of photosynthesis
• The actual rate of photosynthesis depends on many different factors
• Glucose from photosynthesis


  Stored as starch, e.g. in potatoes
• Leaf structure


  • Palisade mesophyll
  • Cuticle
  • Epidermis
  • Spongy mesophyll
  • Guard cells and stomata
  • Xylem
  • Phloem
• Xylem


  Carries water upwards from roots to leaves
• Phloem


  Carries food and ions downwards from leaves to roots
• Factors affecting transpiration rate

  • Bright light
  • High temperature
  • High wind
  • High humidity
• Phototropism


  Growth towards light
• Geotropism/Gravitropism


  Growth towards gravity
• Gibberellins


  Important for growth
• Ethylene


  Important for ripening plants
• Auxins


  Important for growth in the right direction