https://padlet.com/puli_dieg01/unepzt3gqjh8 en-us 2017-10-23 16:07:55 UTC 2025-10-20 07:37:16 UTC hello@padlet.com puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199658889 Photosynthesis is the process that fuels ecosystems and replenish's earth's atmosphere with oxygen. Photosynthesis can be measured by either the disappearance of substrate or accumulation of by-products.
There are two parts of photosynthesis
1. Light reaction
2. Calvin Cycle
Reactants for photosynthesis are carbon dioxide and water
The products are glucose sugar and oxygen
The location for light reactions are in the thylakoid membrane and uses light energy to produce ATP and NADPH
The equation for Photosynthesis is
6CO2 + 6H2O —> C6H12O6 + 6O2
Or: carbon dioxide + water —> glucose + oxygen + water

Experiment outline
The purpose of the experiment was to determine the differences of the rate of photosynthesis between lettuce leaves and spinach leaves. This would be determined by using cut out disks of each leaf, and placed into a mixture of soap and water. The time that it took for the disks to rise to the top of the solution filled beaker, would determine its rate of photosynthesis. Basically, the faster the disks rise to the top, the faster that leaf's rate of photosynthesis.

Hypothesis
The hypothesis for this set of experiments was: "If the rate of photosynthesis is compared between lettuce and spinach leaves, then the rate of photosynthesis will be slower in the lettuce leaves." This hypothesis was introduced due to the difference of color in the two leaf types. The color in the spinach was quite darker than that of the lettuce, showing that the spinach contained more chlorophyll than the lettuce leaf. Therefore, the rate of photosynthesis would be faster in the spinach leaf.

Variables
The independent variable of the lab was the changing of the type of leaf used in the lab. The dependent variable is the time that it takes for the disks to rise in the beaker. The control group is the baseline set of experiments.



]]> 2017-10-23 16:17:10 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199658889 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199807606 2017-10-23 23:23:24 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199807606 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199808132 It was noticed that the lettuce leaf were of a lighter color than that of the spinach leaf. This indicates that the lettuce leaf has less chlorophyll than the spinach leaf. This could be a possible reason for a slower rate of photosynthesis in the lettuce leaf.]]> 2017-10-23 23:27:44 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199808132 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199814830 2017-10-24 00:21:45 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199814830 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199815530 2017-10-24 00:27:38 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199815530 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199817324 2017-10-24 00:40:22 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199817324 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199818413 2017-10-24 00:47:23 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199818413 puli_dieg01 https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199826730 Overall, the original hypothesis was accepted. It stated: : "If the rate of photosynthesis is compared between lettuce and spinach leaves, then the rate of photosynthesis will be slower in the lettuce leaves." The rate of photosynthesis was in fact slower in the lettuce leaves. With data, the lettuce leave's rate of photosynthesis was 41% slower than that of the spinach leaf. The ET50 also had quite of a difference. The lettuce leaves took 21% longer for 5 disks to rise up.

Errors/Improvements
There were also quite a few common errors throughout the experiments, such as pulling too hard on the injector when using the vacuum method on the disks before preparing them for the experiment. This would lead to the injector exploding and causing for the disks to be lost. Another error would be that the light would be forgotten to be turned on before each experiment, and the procedure would need to be started over. Some improvements for the lab would be:
1. Use the "interval feature" on the stopwatch to make it easier to calculate average rates and ET50 and remove the need for mathematical work.
2. Make sure that the light is aimed directly over the  beaker holding the disks to make sure it is accurately simulating natural sunlight.]]> 2017-10-24 01:37:59 UTC https://padlet.com/puli_dieg01/unepzt3gqjh8/wish/199826730