Effect of Light Intensity on Photosynthesis Rate

• What is the focus of the practical experiment described?

  Effect of light intensity on photosynthesis rate
• What is used to measure the rate of photosynthesis in the experiment?

  O₂ bubble in capillary tube
• What does the length of the bubble in the capillary tube represent?

  Rate of O₂ production
• How is the rate of photosynthesis calculated in this experiment?

  Rate (cm/min) = length of bubble (cm) / time (min)
• What happens to the rate of photosynthesis with higher light intensity?

  It increases the rate of O₂ production
• What is the independent variable in this experiment?

  Distance from light source
• What is the dependent variable in this experiment?

  Length of the bubble
• What materials are needed for the experiment?

  • O₂ bubble water in capillary tube
  • Ruler
  • Light source
  • Clamp
  • Small O₂ bubbles
  • Pondweed
  • Syringe to move bubble
• What is the procedure for varying light intensity in the experiment?

  • Repeat experiment
  • Use ruler to vary distance between plant and light each time