The effect of concentration of enzyme and enzyme substrate on the rate of an Enzyme-catalysed reaction

Essay by scheckaHigh School, 12th grade March 2006

download word file, 13 pages 0.0

Downloaded 84 times

This experiment will be an investigation into enzyme activity. Wherever enzymes are used one has to bear in mind that there are various factors which affect the enzyme activity.

I will be investigating how different concentrations of the enzyme catalase affect the rate at which hydrogen peroxide is broken down into water and oxygen. In order of doing this different concentrations of liquid catalase that is gained from dried yeast will be added to a fixed volume and concentration of hydrogen peroxide for a fixed time length.

Enzymes are protein molecules that function as catalysts, that is they can speed up a chemical reaction while not being transformed in that reaction. They work by lowering the activation energy of a chemical reaction. In order to bring to reactants together, energy has to be expended. Enzymes lower that energy barrier. When discussing enzyme catalyzed reactions, the participants in the reaction are called the substrates.

Enzyme exert their effect on chemical reactions by providing a place for the

substrates to interact and in some cases by introducing strain in the substrate molecules. Enzymes are proteins which have a complex three dimensional structure (tertiary structure). Somewhere within the structure is a place where the substrate or substrates can interact with the enzyme; this is called the active site and the structure formed by the interaction is called the enzyme-substrate complex.

One important characteristic of enzymes is that they are specific. Because of the structure of the active site, only one substrate or a group of structurally related substrates can interact with a given enzyme. This means that there must be an enzyme for each reaction that the cell needs to perform. Conversely, if the cell does not contain an enzyme that can interact with a particular substrate, that substrate will not be converted...