Photosynthesis Limiting Factors

Investigate how light, CO2, and temperature affect the rate of photosynthesis.

Procedure

Aim

To investigate the effects of light intensity, carbon dioxide concentration, and temperature on the rate of photosynthesis in an aquatic plant (Elodea).

Step-by-Step Procedure

  1. 1

    Place a freshly cut Elodea shoot upside down in a beaker of NaHCO3 solution.

  2. 2

    Set the desired temperature using the water bath.

  3. 3

    Adjust the light intensity by changing the lamp power or distance.

  4. 4

    Allow the plant 2 minutes to equilibrate with the new settings.

  5. 5

    Count the number of oxygen bubbles released from the cut stem for 1 minute.

  6. 6

    Repeat the process for different values of your chosen independent variable.