Observing Photosynthesis This is a very simple lab that allows students to observe the formation of oxygen bubble during photosynthesis. This lab can be done as a demonstration to begin the unit, or it can done as an inquiry lab where students try to devise an explanation for the … Place a 6 cm Elodea stem with leaves in tubes #1, 2 and 4. Fill tube # 4 with tap water and add 0.5 ml of stock phenol red solution. 8.

Tightly screw the caps on each tube and record the color of each tube on your worksheet. Why did the solution that contained Elodea maintained in light change from pale yellow to red?. Answers to questions. 5. Fill tubes #1, 2 and 3 with the CO 2 enriched phenol red solution.

The phenol red turned yellow after only a couple seconds of me blowing into it with a straw. How long did it take to observe a color change in the phenol red? 6.

As a result, carbon dioxide was removed from the solution. 9. Tube #3 will not have any Elodea. What does the color change indicate in terms of the Elodea plant?

When the sprig of Elodea was added to the solution and placed in the light, the Elodea continued to photosynthesize. 7.

It indicated the carbon dioxide that plants need to go through photosynthesis.