PURPOSE
Do intensity and wavelength affect plant growth?
MATERIAL
Black paper
Blue plastic
Iodine
Test tubes
Water heater
Beaker 400ml
Petri dish
Alcohol
Green plant
Red plant
Tweezers
Scissors
Tape
Dropper
Blue plastic
Iodine
Test tubes
Water heater
Beaker 400ml
Petri dish
Alcohol
Green plant
Red plant
Tweezers
Scissors
Tape
Dropper
PROCEDURE
1. Make a hypothesis
Hypothesis: The blue wrapped leaves will cause blue wavelengths to not to get to the leaves, causing less chlorophyl to grow because blue wavelengths are the best for plant growth due to the fact that they are the easiest for leaves to absorbe. The black paper will let less intensity of light hit the leaves, also causing less chlorophyl growth, because when you have more light intensity, you have more light energy to help the plant grow.
2. Cut off experimental/ control leaves
3. Extract chlorophyl with alcohol
4. Rinse the leaves with water
5. Place in petri dish and cover with iodine
6. Wait 1 minute and remove the leaf onto paper towel
7. Record results
Hypothesis: The blue wrapped leaves will cause blue wavelengths to not to get to the leaves, causing less chlorophyl to grow because blue wavelengths are the best for plant growth due to the fact that they are the easiest for leaves to absorbe. The black paper will let less intensity of light hit the leaves, also causing less chlorophyl growth, because when you have more light intensity, you have more light energy to help the plant grow.
2. Cut off experimental/ control leaves
3. Extract chlorophyl with alcohol
4. Rinse the leaves with water
5. Place in petri dish and cover with iodine
6. Wait 1 minute and remove the leaf onto paper towel
7. Record results
DATA
ANALYSES/CONCLUSION
Iodine indicates for starch. The blacker the iodine, the more starch present. What chloroplast do is they produce energy (starch). Therefore, we are able to tell how much chloroplast was able to grow based on the color the iodine turns the leaf. The reason we had to rinse the leaf with alcohol was to rid of the green chlorophyll already in the leaf so it didn't not interfere with our result. With the green plant, we expected to get darker indication for the natural (uncovered) leaf. However, we ended up with the opposite results. This was an error on our part because we know that the natural leaf should have been most chloroplast filled. Various human errors led to this data such as using incorrect amounts of iodine, not covering the leaf fully, and incorrectly putting the leaf in the alcohol. What we should have got was that the black paper covered leaf resulted in less chloroplast growth because less light intensity was able to enter the leaf, meaning less energy to grow chloroplast. With the blue plastic, less growth was expected because blue is the best wavelength for plant and chloroplast growth.
With the red plant, we know that red and blue wavelengths are the best for growth. We also know that when something is visibly a color, it just means that it is reflecting that one color. Therefore, our data is correct when we conclude that green leafs grow better because they are not reflecting the red wavelength, which the red leaves are doing.
With the red plant, we know that red and blue wavelengths are the best for growth. We also know that when something is visibly a color, it just means that it is reflecting that one color. Therefore, our data is correct when we conclude that green leafs grow better because they are not reflecting the red wavelength, which the red leaves are doing.
REFLECTION
This lab was rather interesting because I had never thought about the different types of light and how they might affect plant growth. I especially didn't understand how the different types of light affected photosynthesis to change plant growth. Learning these new things made this lab very interesting, and at first, very confusing. Next time what I would do differently is fully understand what we were testing for before we started the lab. I was really confused in the beginning because I had no idea what we were doing exactly. Also, I was confused after the lab about how photosynthesis and light worked together, but I asked my teacher to explain it and that really helped. My group collaborated very well. Kyle Rockwell, Brandon Kelly, and Brian Blaire were my lab partners. We each had specific jobs and it made the lab efficient. For example, Kyle would clean the leaves off, while I would poor Iodine on them and Brandon would put them on paper towels.