factors affecting photosynthesis

• Factors affecting photosynthesis


  • Light intensity
  • Temperature
  • Concentration of carbon dioxide in the air
  • Amount of chlorophyll in plants
• Chlorophyll


  Pigment within chloroplasts that absorbs the light energy needed for photosynthesis
• Plants have less chlorophyll


  They won't be able to carry out as much photosynthesis
• Different plants will naturally have different amounts of chlorophyll
• The level of chlorophyll within an individual plant can vary due to disease, environmental stress or lack of nutrients
• Factors that damage chloroplasts and reduce chlorophyll production include disease, environmental stress, and lack of nutrients
• Limiting factors for photosynthesis

  • Light
  • Carbon dioxide
  • Temperature
• Graphing limiting factors for photosynthesis

  1. Plot light intensity on x-axis

  2. Plot rate of photosynthesis on y-axis

  3. As light intensity increases, rate of photosynthesis increases until it plateaus

  4. Plateauing indicates another factor is limiting
• Graphing carbon dioxide as a limiting factor

  1. Rate of photosynthesis increases with carbon dioxide concentration until it plateaus

  2. Plateauing indicates another factor is limiting
• Graphing temperature as a limiting factor

  1. Rate of photosynthesis increases with temperature initially

  2. Rate starts to drop as enzymes denature above 45 degrees
• Everything from here on is higher tier GCSE biology
• Multiple limiting factors shown on one graph

  Comparing curves at different temperatures or CO2 concentrations shows which factor is limiting
• Techniques farmers use to optimize photosynthesis

  • Use greenhouses to trap heat and provide artificial light
  • Pump in extra carbon dioxide
  • Use fertilizers to provide essential minerals
  • Use pesticides to control pests
• Optimizing photosynthesis conditions can be costly for farmers