BIOLOGY-limiting factors

• What should you be able to do by the end of the video?

  Interpret graphs and explain greenhouse use
• What is the equation for photosynthesis?

  Light energy + CO2 + water → glucose + oxygen
• What happens to the rate of photosynthesis when light intensity increases?

  It initially increases, then levels off
• What does it indicate if the rate of photosynthesis stops increasing with higher light intensity?

  Light intensity is no longer the limiting factor
• What are the three other factors that limit photosynthesis?

  Carbon dioxide concentration, temperature, chlorophyll
• How does increasing carbon dioxide concentration affect photosynthesis?

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

  The rate of photosynthesis does not change
• What effect does increasing temperature have on photosynthesis?

  It can increase the rate of photosynthesis
• What happens if the temperature is increased too much?

  Enzymes in the leaf will denature
• What can act as limiting factors in photosynthesis?

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

  • Provide controlled light and heat
  • Add extra carbon dioxide
  • Increase crop yield
• Why is it expensive to maintain optimal conditions in greenhouses?

  Due to costs of heating and CO2 addition
• What do some gardeners use to release heat and carbon dioxide?

  Oil burners
• What should you remember about limiting factors in photosynthesis?

  They are frequently tested in exams
• What is the main product of photosynthesis?

  Glucose
• What is a byproduct of photosynthesis?

  Oxygen
• What role does chlorophyll play in photosynthesis?

  It absorbs light energy
• How can farmers justify the costs of greenhouse maintenance?

  By increasing crop yield