Name: Chan Ka Wing 6D(1)
Title: Investigation of the effect of light intensity on the rate of photosynthesis
Objective: To investigate the effect of light intensity on the rate of photosynthesis
Principle: why this method?
Apparatus and materials:
1 pipette filter
1 boiling tube
1 stand and clamp
1 60-watt bench lamp
1 razor blade
1 meter ruler
1 rubber tubing
0.25% sodium hydrogencarbonate solution
1. The razor blade is very sharp. We should handle it with care.
1. Cut the stem of a Hydrilla plant to about 10cm long under water.
2. Set up the apparatus as shown below. Check the thermometer at intervals to ensure a constant temperature. Renew the water if necessary.
3. Adjust the distance of the bench lamp to 0.1m from the Hydrilla plant. Turn on the lamp and allow the plant to equilibrium for 5 minutes.
4. Suck up the solution from the boiling tube. Close the clip completely Record the starting position of the meniscus in the pipette.
5. After 5 minutes, record the final position of the meniscus in the pipette. Calculate the rate of photosynthesis. Record two more readings.
6. Repeat steps 2 to 5 with the bench lamp placed at a distance of 0.2m,0.3m,0.4m and 0.5m from the Hydrilla plant.