Carbon Fixation in Elodea

Analysis:

1. Phenol red changed colors when we blew into the tube because adding CO2 lowers the pH level and Phenol red is a substance that changes colors as the acidity is changed. Its color change indicated that the pH level was lowered by the CO2.
2. It took roughly 5-10 minutes to see a color change when we blew into the Phenol red. However, it took about 30 minutes to see a color change when we added the Elodea plant. The color change in the Phenol red with the Elodea Plant indicated that the plant had been photosynthesizing the CO2.
3. The Phenol red and Elodea light independent tube did not photosynthesize. This is because light is a key factor to photosynthesis and is not possible without it.
4. I did not see a change in color of the phenol red test tube with no elodea. This is because the elodea had been sucking up the CO2 for photosynthesis, and the elodea independent tube had not. Therefore, the acidity did not change.
5. Carbon fixation does not occur in humans. However, it does occur in some bacteria. Other than that, plant are the most well known for their carbon fixation.
6. A plant uses carbon + H20 + light to build simple sugars like glucose and fructose. Unlike many other living organisms, plants can make food energy instead of just being able to break it down.
7. Having a control in this experiment is important because we can manipulate the light component. Our control allows us to see that light is needed in order for photosynthesis to occur.