Carbon dioxide and oxygen are produced by two different reactions: carbon dioxide is produced during cellular respiration and oxygen is the product of photosynthesis. 

Cellular respiration uses up oxygen. Sugars power respiration producing carbon dioxide and water as waste products. Cells use sugars to keep things hopping. All sugars end in OSE so glucose, sucrose, and fructose are all sugars.

In this graph organisms were placed into a test tube along with a sugar and then the test tube was capped. The organism was monitored over a 24 hour period. After 24 hours all the sugar was gone.