If photosynthesizing green algae are provided with CO2 containing heavy oxygen (18O), later analysis will show that all of the following molecules produced by the algae contain 18O except If photosynthesizing green algae are provided with CO2 containing heavy oxygen (18O), later analysis will show that all of the following molecules produced by the algae contain 18O except ribulose bisphosphate (RuBP). O2. 3-phosphoglycerate. glucose. glyceraldehyde 3-phosphate (G3P).