During what cycle do a series of reactions occur in the mitochondria which release carbon dioxide and produce some atp?

The appropriate answer in the KREBS CYCLE. The Krebs cycle is also called the citric acid cycle. It is a cyclic reaction series involving several carboxylic acids in the mitochondrial matrix. Acetyl groups are oxidized to carbon dioxide while reducing specific co-enzymes. These co-enzymes are now available for ATP synthesis. This cycle or process occurs in the cells mitochondria.  

The answer to this will be from your lab notes/procedure. it would be best to ask another student who participated in the lab as we do not know what was done, what enzyme or if the temperature is celsius or fahrenheit. if i were to guess though i'd say the rate stopped due to enzyme denturing at high temperature

The casefor proofs