If photosynthesizing green algae are provided with CO₂ synthesized with heavy oxygen (¹⁸O), later analysis will show that all but one of the following compounds produced by the algae contain the ¹⁸O label. That one is
A)PGA.
B)PGAL.
C)glucose.
D)RuBP.
E)O₂.

Question

Quizplus · Accepted Answer

During photosynthesis, the oxygen released as a byproduct comes from the splitting of water molecules, not from CO₂. Therefore, the O₂ produced will not contain the heavy oxygen label from the CO₂.

If Photosynthesizing Green Algae Are Provided with CO₂ Synthesized with Heavy