Cassandra made a venn diagram to compare and contrast the two stages of cellular respiration.
which belongs in the area marked x?
energy is released.
oxygen is used up.
glucose is broken down.
carbon dioxide is used up.

Energy is released.

Cellular respiration is broadly divided into two stages, the first stage is called glycolysis and the second stage is the Krebs cycle or TCA cycle. Glycolysis occurs in the cytoplasm of the cell in which one molecule of glucose is broken down into two molecules of pyruvic acid and a small amount of energy. Krebs cycle occurs in mitochondria, further breakdown of the respiratory intermediate is done to produces a large amount of energy. In the given question, an area marked X represents a common feature of both the stages of respiration which is ‘energy is released’ in both stage one and stage two.  

I cant be expected to answer this with out a venn diagram

oxygen +1 most likely

not sure what it is