500
A student is conducting an experiment with plants and animals living in the same environment. She placed water, a small amount of soil, a few green aquatic plants, and a fish in a large plastic two-liter bottle filled with water. It was sealed with an air-tight cap and placed near a window so it could receive sunlight during the day, but not at night. Which gas(es) is the plant giving off over the entire 24 hour period?
What is O2, CO2, & H2O?