Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2

The question is incomplete. The complete question is - A student poured a solution of bromthymol blue indicator into three test tubes. Then, he placed and aquatic plant in two of the test tubes, as shown below. He placed a stopper on each test tube and placed them all in the dark for 24 hours. Brothymol blue turns from blue to yellow in the presence of CO2.

Which process would you expect the organisms in the test tubes to carry out-- cell respiration, photosynthesis or both? When would you expect each process to occur?

Photosynthesis is the process of the formation of the food in case of plants in the presence of sunlight with the help of carbon dioxide, water and soil. The light energy is converted into the chemical energy.

The beaker is blue because plants uses carbon dioxide for their food preparation. When the beakers are kept in the dark place, instead of photosynthesis cellular respiration occur that made energy from the food for their survival.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: