The Effect Of Temperature On Enzyme Activity

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The Effect of Temperature on Enzyme Activity

Experiment:

To investigate the effect of temperature on enzyme activity. The enzyme used will be catalyse.

The enzyme catalyse:

The enzyme catalyse is a biological enzyme. It is used to break down Hydrogen Peroxide, which is harmful. The reaction that occurs is:

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Hydrogen peroxide Water + Oxygen

The activity of the enzyme catalyse can therefore be measured by the amount of oxygen (in the form of froth) that is produced.

Prediction:

The enzyme catalyse will have an optimum temperature of between 40‹-45‹. If the temperature rises above this temperature range or below this temperature range, the rate of enzyme activity …show more content…

If the temperature rises above this, the enzyme activity will slow down because the enzyme will be denatured. This means that the active site will be changed. Enzymes only work if the substrate fits into to the enzymes active site, like a lock and key (see diagram). The reaction then takes place and the product leaves. If the active site shape is changed the substrate will no longer be able to fit in (see diagram). This means that the reaction can no longer take place.

As the temperature gets higher above 45‹C, more enzymes will be denatured. The higher the temperature above 45‹C, the slower the reaction rate.

If the temperature falls below 40‹C, the rate of enzyme activity will fall. This is because the lower the temperature, the less kinetic energy the enzymes will have. This means that fewer will be able to react. The lower the temperature below 40‹C, the slower the enzyme reaction rate. At low temperaturefs particles of reacting substances do not have much energy. However, when the substances are heated, the particles take in energy. This causes them to move faster and …show more content…

At 10‹C the particles of the catalyse have less kinetic energy, so collide with the particles of the hydrogen peroxide with less energy. Therefore a reaction is less likely to take place, and less oxygen (in the form of froth) is produced. As the temperature rises the particles have more kinetic energy, so collide with more energy and produce more oxygen. This accounts for the steep rise in the gradient of the graph between 10‹C and 20‹C.

The activity of the enzyme catalyse decreases at higher temperatures because enzymes are proteins, and proteins are denatured at high temperatures. Denaturing is where the active site of the enzyme is changed, so the substrate (in this case hydrogen peroxide) can no longer fit into it. Enzymes only work if the substrate fits into to the enzymes active site, like a lock and key. The reaction then takes place and the product leaves. If the active site shape is changed the substrate will no longer be able to fit in. This means that the reaction can no longer take place, decreasing the amount of oxygen produced. Biological variation means that not all of the

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