Claire's Research

Today I spent 2 hours researching about the general topics of our project: light and color. Here is what I found-

• Light can be defined as an electromagnetic wave. It is a radiant energy that consists of electromagnetic radiation. Visible light has a wavelength in the range of about 400-700 nanometers. For our experiment it is important to understand how the different characterstics of various light colors affect the CO2 emission of plants. To understand this I researched what parts of light affect the things it shines on. 
•  Different colors of light have different energy levels. The highest energy light is purple/violet. This means purple/violet light has short wavelengths. The lowest energy light is red, meaning it has the longest wavelengths. The shorter a wavelength, the more energy a color has. This concept is important in our experiment because the wavelength of the various color light filters we use may affect the about of CO2 that is drawn out of the plant.
• I also decided to see what affects the rate of CO2 emission in plants. During a plant's lifetime, it gives off about half of the carbon dioxide that it absorbs (but the exact amount varies based upon plant type). During the process of photosynthesis, plants use energy from the sunlight to convert carbon dioxide and water into sugars. When plants burn these sugars for food, carbon dioxide is produced as a waste product. During the day the sun powers photosynthesis, and plants absorb much more CO2 than they give off. At night they give off much more CO2 than they absorb. We will need to keep this in mind as we will most likely be measuring carbon dioxide output during the day for our experiment.
• When natural sunlight shines on a plant, it is absorbing the entire color spectrum, except for green which it reflects and is why plants appear green. Plants primarily absorb red and blue light. In the plant's chloroplast, the molecules that actually absorb color are called photopigments. All plants have a mix of different types of photopigments so that they can absorb different colors of light. If there was only one color of light shining on a plant only one group of photopigments would be activated and the plant wouldn't be able to make as much sugar as it would if it absorbed the entire spectrum of light. In general the plant won't survive as long with one color light as compared to the entire light spectrum. For our experimental purposes, I think we can predict to see much more carbon dioxide emission under the white light filter than the red, yellow, blue or black filters because under the white light all of the photopigements will be active and producing sugars and completing the cycle of photosynthesis.

Overall, I think my research will be very beneficial in developing our experimental design.

Here are my sources:

http://van.physics.illinois.edu/qa/listing.php?id=2000

http://scienceline.ucsb.edu/getkey.php?key=2853

http://scienceline.ucsb.edu/getkey.php?key=826
http://scienceline.ucsb.edu/getkey.php?key=3155

Meeting #1

Today all four of us met at the library to brainstorm potential project topics. After looking on the internet for ideas and talking with the group we came up with the idea to test how light color affects the mass of CO2 produced in daisy flowers. The flowers are the biology side of the experiment and the CO2 is the chemistry side of the experiment.

We met for 2 hours today and came up with the experiment design. Then we agreed to each go home and individually do 2 hours of research each and each create a blog post explaining what we learned.

Here's what we decided on today:

Research question- How does light color affect the mass of CO2 emitted by daisies?

Hypothesis- We predict, based upon our knowledge of color absorption and reflection, that the black light will produce the least mass of CO2.

Independent variable- different light colors (red, blue, yellow, white, black)

Dependent variable- mass of CO2

Controlled variables- type of plant, type of soil, light, temperature, light level of flash lights

Procedures- 1. Put on goggles and lab aprons
2. gather together all the materials on the material list
3. Cut holes into the tops of the cardboard boxes
4. Tape shrink wrap over the cut holes
5. Cut out 6 x 6 squares of colored transparent plastic
6. Tape the squares of plastic over the flashlight bulbs
7. Test the light emissions of the flashlights with the light probe. Record
8. Tape the flashlights to the top of the fume hood (in the chemistry or biology classroom
9. Label the plants as R#1-#5, B#1-#5, Y#1-#5, W#1-#5, Black#1-#5
10. Place R1, B1, Y1, W1, Black 1 underneath their respective flashlights
11. Place the 5 greenhouses over the plants. Record initial CO2 mass
12. Turn on flashlights. Let sit 30 minutes
13. Turn off flashlights. Record CO2 mass
14. Repeat steps 1-13 four additional times

List of materials and equipment- 25 generic plants (possibly daisies), temperature probe, red filter, blue filter, yellow filter, white filter, black filter, light probe, pH probe, batteries, 5 plastic greenhouses (shrink + cardboard boxes), CO2 probe, 5 flashlights, tape, 2-3 pounds of soil, 4 iPads