Factor affecting photosynthesis

• What are the three ways to measure the rate of photosynthesis in the lab?

  Oxygen output, carbon dioxide uptake, carbohydrate production
• Why are the methods of measuring photosynthesis not perfect?

  Because plants also respire, affecting measurements
• What factors can affect the rate of photosynthesis?

  • Light intensity
  • Carbon dioxide concentration
  • Temperature
  • Amount of chlorophyll
• How does light intensity affect photosynthesis?

  Increased light intensity raises the rate of photosynthesis
• What happens to photosynthesis at very high light intensities?

  Photosynthesis is slowed and then inhibited
• What role does carbon dioxide play in photosynthesis?

  It is a reactant in the photosynthesis process
• What happens to the rate of photosynthesis when carbon dioxide concentration increases?

  The rate of photosynthesis increases
• How does temperature affect the rate of photosynthesis?

  Temperature affects enzyme activity in photosynthesis
• What occurs at low temperatures regarding photosynthesis?

  The rate is limited by molecular collisions
• What happens to enzymes at high temperatures?

  Enzymes become denatured and lose function
• What is the function of chlorophyll in photosynthesis?

  It absorbs light energy for glucose production
• Why is chlorophyll green?

  It absorbs red and blue light, reflects green
• What is the compensation point in photosynthesis?

  • The light intensity where photosynthesis equals respiration
  • Graphs of oxygen production or carbon dioxide uptake do not start at the origin
• How do respiration and photosynthesis affect the graphs of oxygen production and carbon dioxide uptake?

  They cause the graphs not to start at the origin