Limiting factors

• What happens to the rate of photosynthesis when light intensity is increased?

  The rate of photosynthesis initially increases with light intensity.
• What does it indicate when the rate of photosynthesis stops increasing despite higher light intensity?

  It indicates that light intensity is no longer the limiting factor.
• What are the three other factors that limit photosynthesis?

  Carbon dioxide concentration, temperature, and amount of chlorophyll.
• How does increasing carbon dioxide concentration affect the rate of photosynthesis?

  Increasing carbon dioxide concentration increases the rate of photosynthesis.
• What happens when carbon dioxide concentration is increased beyond a certain point?

  The rate of photosynthesis does not change because there is plenty of carbon dioxide available.
• What effect does increasing temperature have on the rate of photosynthesis?

  Increasing temperature can increase the rate of photosynthesis until enzymes start to denature.
• What happens to enzymes in the leaf if the temperature is increased too much?

  The enzymes will start to denature, causing the rate of photosynthesis to fall.
• What can act as limiting factors in photosynthesis?

  Light intensity, carbon dioxide concentration, temperature, and amount of chlorophyll.
• How do greenhouses increase the rate of photosynthesis?

  • Farmers light and heat their greenhouses.
  • They add extra carbon dioxide.
  • This increases the yield of crops.
• Why is it expensive to increase the rate of photosynthesis in greenhouses?

  Because the costs of lighting, heating, and adding carbon dioxide must be justified by the increase in yield.
• What do some gardeners use to release heat and carbon dioxide simultaneously?

  Oil burners.
• What are the key concepts related to limiting factors in photosynthesis?


  • Light intensity can limit photosynthesis.
  • Carbon dioxide concentration can limit photosynthesis.
  • Temperature can limit photosynthesis.
  • Amount of chlorophyll can limit photosynthesis.