Answer;
Flask 2 only;
Reason; Because the fish produce CO2 as products of cellular respiration and do not undergo photosynthesis therefore not consuming CO2.
Explanation;
- Cellular respiration is the process by which food substances such a glucose and fructose are broken down to produce energy in the form of ATP, and water aand carbon dioxide as by products.
- The process of cellular respiration takes place in both plants and animals, however in plants the carbon dioxide produced from cellular respiration is used for the process of photosynthesis.
- Bromothymol blue is a chemical indicator solution that changes color from blue to yellow in the presence of CO2. Therefore, in since the fish produced carbon dioxide which is not used for photosynthesis like in plants, the Bromothymol blue turned yellow in flask 2.