The Effect of Catalase Concentration on Rate of Reaction
Abstract
The following experiment details the effect of different concentrations of catalase on the production of oxygen and water through the breakdown of Hydrogen Peroxide. In this experiment paper disc where coated in varying concentrations of catalase, 0, 25, 50 75 and 100%. The time taken for the disc to float between two markers on the side of a glass was then recorded. This experiment demonstrates that the higher the concentration of enzyme used the greater the production of oxygen on the paper disc. The oxygen then produced on the disc gives it greater buoyancy allowing it to move past the markers faster.
Aim
To find the effect of the enzyme concentration on the reaction between Catalase and hydrogen peroxide.
Introduction
Enzymes are proteins that act as catalysts (a substance that increases or decreases the rate of a reaction) 2. Enzymes bind to a molecule called a substrate, converting it into a product. Nearly all of the chemical reactions that occur in a biological cell need enzymes to make them occur. Enzymes like all catalysts lower the activation energy needed for a reaction to take place3. They dramatically speed up the rate at which the reactions take place3. They are not consumed by the reaction and remain unchanged by the reaction it self3. Enzymes have been linked to nearly 4000 biochemical reactions. Enzymes are very specific to the reaction in which they catalyse3.
In 1894 it was suggested because of the specific nature of enzymes for their substrate the enzyme posses a complementary shape to the substrate4. The enzyme and the substrate fit exactly together without any need for changes in structure. This was called the lock and key model as the substrate fits exactly into the hole on the enzyme4. Although this model explains the specificity of the reaction it does not explain how the enzyme lowers the activation energy for the reaction to take place. In 1958 Daniel Koshland suggested a more flexible model5. The Induced Fit model
The following experiment details the effect of different concentrations of catalase on the production of oxygen and water through the breakdown of Hydrogen Peroxide. In this experiment paper disc where coated in varying concentrations of catalase, 0, 25, 50 75 and 100%. The time taken for the disc to float between two markers on the side of a glass was then recorded. This experiment demonstrates that the higher the concentration of enzyme used the greater the production of oxygen on the paper disc. The oxygen then produced on the disc gives it greater buoyancy allowing it to move past the markers faster.
Aim
To find the effect of the enzyme concentration on the reaction between Catalase and hydrogen peroxide.
Introduction
Enzymes are proteins that act as catalysts (a substance that increases or decreases the rate of a reaction) 2. Enzymes bind to a molecule called a substrate, converting it into a product. Nearly all of the chemical reactions that occur in a biological cell need enzymes to make them occur. Enzymes like all catalysts lower the activation energy needed for a reaction to take place3. They dramatically speed up the rate at which the reactions take place3. They are not consumed by the reaction and remain unchanged by the reaction it self3. Enzymes have been linked to nearly 4000 biochemical reactions. Enzymes are very specific to the reaction in which they catalyse3.
In 1894 it was suggested because of the specific nature of enzymes for their substrate the enzyme posses a complementary shape to the substrate4. The enzyme and the substrate fit exactly together without any need for changes in structure. This was called the lock and key model as the substrate fits exactly into the hole on the enzyme4. Although this model explains the specificity of the reaction it does not explain how the enzyme lowers the activation energy for the reaction to take place. In 1958 Daniel Koshland suggested a more flexible model5. The Induced Fit model
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