1. Photosynthesis

2. Purpose
The purpose of this experiment is to determine the difference in the rate of photosynthesis in the presence of red, blue, and white light.

3. Hypothesis
Hypothesis: If a plant leaf is exposed to natural light it will have a higher rate of photosynthesis than plant leaves exposed to artificial light.
If plants are exposed to blue, red, and white artificial light, then the plant exposed to blue light will have the highest rate of photosynthesis, followed by white and then red.

4. Background Information
Plants use sunlight to drive photosynthesis. 
CO2+H2O -> O2 C6H12O6​
Light bulbs usually do not provide the full spectrum of light found in natural sunlight.
Sun light is absorbed most efficiently by plants at certain wavelengths. Red and blue are the most efficient while green is the least.
that is why leaves are green, the green light is reflected.
(add some graphic about photosynthesis?)

6. Materials
Soybean Plant
Light Box Access to Sunlight* 120V 13W Fluorescent Energy Saving Light Bulb (Blue) 120V 13W Fluorescent Energy Saving Light Bulb (Red) 120V 13W Fluorescent Energy Saving Light Bulb (White) Hole Punch Baking Soda (1 teaspoon in each cup) Liquid Dish Soap (Dilute) Water (150 ml in each cup) Plastic Cups (x3) Plastic Syringes (x3) Stopwatch * Not available, used substitute

7. Time Red Blue White P Value

8. Number of Floating Disks vs. Time

9. Interpretation of Data
The disks exposed to blue light floated to the surface both faster and more often.
Both the blue and white disks show similar trends in that there is a period in the beginning of the trial when no disks float.
After several minutes (four for the blues, nine for the whites), two disks come to the surface. More disks float in the minutes following the first disks. Interestingly, no more than five white disks ever come to the surface.
All eight blue disks eventually float. The white disks display a plateau after four disks have floated, with the fifth surfacing only after eight minutes.
One might expect a linear increase in floating disks starting a few minutes in. The disks exposed to red light did not float and have been excluded from this graph.
The p-value suggests that there is a % chance that these results happened by chance, rejecting the null hypothesis.

10. Limitations Implications/limitations:
The results suggest that, as expected, the Blue light is very effective at fueling photosynthesis.
The data from the red bulb test however, was the opposite of what prior knowledge would have predicted.
This would suggest that something in the procedure was incorrect or an unknown variable interfered.
Because of a lack of sunlight, no trials were run with natural light. This limits the extent to which we can say any artificial light is effective, because we cannot compare it to the preferred control.
Because of this white light is used as a sub optimal control.
The time constraints severely limited the amount of trials run. For any data gathered in this experiment to me reliable, the trials would need to be run many more times, with sunlight trials for comparison, and with more bulb colors and more plant species.

11. Works Cited
Vivian, John. "Total-control indoor gardening with modern hydroponics." Mother Earth News Oct.-Nov. 1998: 36+. Science in Context. Web. 30 Mar
Ensminger, Peter A. "Photosynthesis." The Gale Encyclopedia of Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. 5th ed. Farmington Hills, MI: Gale, 2014. Science in Context. Web. 30 Mar
"Photosynthesis, Light Reactions and." Plant Sciences. Ed. Richard Robinson. New York: Macmillan Reference USA, 2001. Science in Context. Web. 30 Mar
"Color." UXL Encyclopedia of Science. Detroit: UXL, 2007. Science in Context. Web. 30 Mar
"Luminescence." UXL Encyclopedia of Science. Detroit: UXL, 2007. Science in Context. Web. 30 Mar ​