Photosynthesis and limiting factors

• What is the balanced symbol equation for photosyntheis

  6CO2+6H2O→C6H12O6+6O2
• word equation for photosyntheis

  carbon dioxide + water ------> oxygen + glucose

  (sunlight)
• What type of reaction is photosynthesis?

  • Endothermic
  • Why? - the plant TAKES IN the sunlight/ absorbs it from the surroundings
  • Endothermic reactions would be any chemical processes that use thermal energy derived from the environment to create finished products
• What factors affect the rate of photosynthesis?

  • Light energy
  • water
  • CO2
  • Chlorophyll
  • Optimal temp for enzymes
• How does light intensity affect the rate of photosynthesis?

  • slows down if there is a limited amount
• What is a limiting factor?

  • In short supply which slows down the process
• How to calculate rate of photosynthesis

  • Bubbles produced per minute on the y axis
• What is the inverse proportion law for light intensity?

  • As the distance increases the light decreases
  • This is because as the distance away from a light source increases, photons of light become spread over a wider area.
• What are the uses of glucose in a plant

  • Cellulose - strengthens cell wall
  • Converted into insoluble starch for storage in the stems, leaves and roots
  • Used for anaerobic and aerobic respiration
  • Combined with nitrate ions absorbed from the soil to produce amino acids for protein synthesis
• what happens to the rate of photosynthesis when temperature increases

  • Higher KE of particles
  • more successful collissions between reactants and enzymes
  • more product is formed
  • if it gets too high, enzymes denature so no prouducts are formed
• what happens to rate of photosynthesis when temperature decreases

  -lower KE of particles

  fewer succesful collissions

  rate decreases
• what is the inverse square law

  1/d2
• why do farmers use greenhouses

  • to gain maximum rate of photosynthesis and growth whilst maintaining profit
• what do greenhouses use to maximise the rate of photosynthesis

  • no shades - allows maximal light
  • artificial lights for darker months
  • ventilation so plants don't over heat
  • heater which burns paraffin to provide CO2
  • watering system to provide max amount of water needed
  • indoors away from pests
• how does glucose help a plant grow

  converted into protein for growth