In this Experiment The Effect of Temperature on Catalase Activity in the Liver and Muscle Tissue of Pigs, it was sought to determine if there is any correlation between temperature and catalase activity in the two different tissue types. The types of tissue used were the muscle and liver tissue of pigs because it has been shown that the anatomy of pigs is very much analogous to that of humans, and therein through a better understanding of the catalase activity in pigs there can be a better understanding of the same activity in humans. This study fits well into the realm of Metabolic Molecular Biology. The study of the catalase activity in different tissue types is important because catalase, along with super oxide dismutase, acts to break down the reactive oxygen species into water and oxygen. This metabolic breakdown is important because the reactive oxygen species has been linked to cancer. Catalase is responsible for detoxifying hydrogen peroxide and preventing the formation of carbon dioxide bubbles in the blood. Large amounts of catalase are generally found in the liver because the liver is one of the organs responsible for the breakdown of toxic material, i.e. the reactive oxygen species and hydrogen peroxide. Studies have shown skeletal muscles generate considerable reactive oxygen during intense muscle contraction. "Evidence that muscle conditioning results in upregulation of antioxidant defenses also suggests a close relationship between reactive oxygen and contractile activity" (Thomas L. Clanton). This experiment saught to determine if the aforementioned generation of reactive oxygen during intense muscle contraction is accompanied by increased catalase levels as well. In using temperature as the independent variable it was intended to recreate the heat stress on the muscle that is often associated with intense physical activity. The liver is a good comparison for the muscle tissue because it is known that with increased reactive oxygen levels catalase levels will also increase, but little is known about the effect of increased reactive oxygen levels and catalase activity in muscle tissue.