Q9 Photosynthesis And Osmosis Flashcards
Investigate the influence of light intensity on the rate of photosynthesis — Procedure
- Place the Elodea into the boiling tube with pond water cut end pointing upwards.
- Add sodium bicarbonate to maintain constant carbon dioxide concentration.
- Place this into the water bath at 20°C and switch on the lamp.
- Place the boiling tube at a measured distance from the light source (e.g., 20cm).
- Allow the plant to adjust for at least 5 minutes
- Record the number of bubbles released per minute. Repeat twice.
- Calculate and record the average number of bubbles released per minute and record the result.
- Repeat the procedure at other measured distances (e.g., 40cm, 60cm, 80cm, 100cm).
Investigate the influence of light intensity on the rate of photosynthesis — Expected Result
• As the light intensity increases, the rate of photosynthesis increases.
• The rate levels off as the saturation point is reached.
Conduct any activity to demonstrate osmosis — Procedure
Not likely as whole question 9
- I softened 2 strips of visking tubing by soaking them in water.
- I tied a knot at one end of each strip.
- I half-filled one tubing with sucrose solution and the other with distilled water (control).
- I eliminated air from the tubes and tied a knot in each end.
- I washed off any excess sucrose solution and dried them.
- I recorded the turgidity of each tube.
- I recorded the mass of each tube.
- I suspended each tube in a beaker of distilled water for 20 minutes.
- After 20 minutes I recorded the turgidity and mass of each tube.
Conduct any activity to demonstrate osmosis — Expected Result and Conclusion
Not likely as whole question 9
Conclusion:
• The visking tubing with sucrose increased in mass AND turgidity.
• The visking tubing with distilled water remained the same.
How do you calculate the rate of photosynthesis
Record the number of bubbles released per minute. Repeat twice.
Calculate and record the average number of bubbles released per minute and record the result.
