Mrs. Alvarez's class is conducting an experiment to assess the exchange of carbon between photosynthesis in elodea plants and cellular respiration in snails. The experiment required the use of a pH indicator that turns yellow in response to a high concentration of a waste product released during these processes. The results are displayed in the table. Test Tubes

Contents

Starting Color

End Color

A

Water

Green

Green

B

Water and 2 snails

Green

Yellow

C

Water and 2 elodea

Green

Green

D

Water, 2 snails, and 2 elodea

Green

Yellow

Which of the following experimental questions is BEST answered through the use of this pH indicator?

A
Is there carbon dioxide in the solution?

B
Is there glucose in the solution?

C
Is there oxygen in the solution?

D
Is there ATP in the solution?