1. Why does the phenol red change color when we blow bubbles into the tube? Phenol red is an indicator in this experiment. What did it indicate?
The phenol red changes color because when we blow through the straw we are adding CO2 to it causing it to change a yellowish color. It indicated the carbon dioxide that plants need to go through photosynthesis.
2. How long did it take to observe a color change in the phenol red? What does the color change indicate in terms of the Elodea plant?
The phenol red turned yellow after only a couple seconds of me blowing into it with a straw. The color change indicates that there is enough carbon dioxide in the phenol red for the plant to go through photosynthesis.
3. If carbon fixation occurs during the light independent stage of photosynthesis, why did the procedure call for placement of the test tubes under the grow light?
It called for us to place the test tubes under the grow light for the other stages of photosynthesis. We covered one of the tubes with foil to prevent any light for entering to see how that would effect the process.
4. Did you see a change in color of the phenol red test tube with no elodea added? Why or why not?
No, because there was no plant to take in the carbon dioxide in the phenol red.
5. Does carbon fixation occur in humans? Can you think of any other organisms that fix carbon?
No, I believe that carbon fixation only occurs in plants.
6. How does a plant use carbon? What is meant by the term carbon fixation?
Plants can reduce the carbon from carbon dioxide to the carbon in the organic compounds which they depend on. This is called carbon fixation. These organisms may be called primary producers or autotrophs.
7. Identify and explain the control in this experiment. What is the purpose in having a control?
When doing any kind of experiment you want to have a control to compare the results of the final product. The control in this specific lab was the tube with no Elodea plant in it so we could observe what exactly the plant does with the phenol red.
No comments:
Post a Comment