Photosynthesis also releases the gas, oxygen. Plants are the most efficient converts of the sun’s energy and all other living organisms depend on them as a source of life.
The equation for photosynthesis is: 6CO2+6H2O> C6H12O6+6O2
Hypothesis:
My prediction for this practical is that the harder the surface, the higher the ball will bounce. The softer the surface, the lower the ball will bounce.
Equipment:
- 1 Tennis Ball
- 1m Rule
- Different Surfaces
Equipment Set up:
Safety:
- Do not throw the ball around, as it may injure someone.
- Only drop the ball when not many people are around.
- Basic lab rules apply
In this experiment there are only few dangers, such as ball might injure someone. Though basic Lab rules should be followed.
FAIR TEST:
To maintain a fair test we have to make sure that we use the same:
- Tennis Ball
- Person Dropping The Ball
Also repeating the test 3 times, to make sure that the results are reasonable.
Method of Experiment:
- Place 1 m Rule on surface, and keeping it upright.
- Dropping the ball from the selected height.
- As soon as the ball reaches its highest position take the measurements.
- Turn light on and begin timer for 2 minutes.
- During allocated time count number of bubbles coming off.
- Record results in table shown below.
- Record steps 4-7 for all measurements.
Variable:
During the experiment, I will change the distance of light from the plant, to see how it affects the rate of photosynthesis. I will do this bye:
- Changing the length that the light is from the test tube, I will move at 10,20,30,40, and 50.
Results
Conclusion:
From the results and graphs that I have gathered I now know that an increase in light intensity certainly does increase the rate of photosynthesis. Also, the relationship between light intensity and the rate of photosynthesis was non-linear. From one of the graphs there is a best-fit curved line. This means that the rate of photosynthesis increases at an exponential rate.
The greater the light intensity the more intense photosynthesis was, the greater the distance, the slower the rate of photosynthesis. Photosynthetic rate is being limited by certain factors such as carbon dioxide and temperature. As light intensity increases further, these factors limit the rate of photosynthesis even more until photosynthesis is completely limited and the graphed line become horizontal. This is when photosynthesis is being carried out at a constant rate.
Evaluation:
Overall, I would state the experiment as a success since my predictions were supported by my results. My prediction needed to be brief, sensible and logical.
While performing the experiment, the piece of pondweed did not photosynthesise at a steady rate, even when the distance from the plant to the light source was kept a constant. This is evident because my graphs were not all exactly the same this was why it is better to carry out the experiment more than once, if this was not done the results may not go down at a steady rate.
While the number of oxygen bubbles was being recorded, the rate at which the plant was photosynthesising had increased several times. This may be due to the poor circulation of sodium hydrogen carbonate at the beginning of the experiment. Carbon dioxide may have initially limited the rate of photosynthesis. Almost all readings were in correlation with each other. A large factor in determining data accuracy is the amount of human error during experiments. To improve the accuracy of the results, the readings would have to be taken several more times.
