preview

The Effect of Substrate Concentration on the Rate of Activity of the Enzyme Catalase

Better Essays

The Effect of Substrate Concentration on the Rate of Activity of the Enzyme Catalase

Background Information:

Enzymes are biological catalysts that increase the speed of chemical reactions without undergoing any physical change. They are neither used up in the reaction nor do they appear as reaction products. All enzyme catalysed reactions are reversible.

Enzymes effectively lower the amount of activation energy required for chemical reactions to start. Some enzymes weaken covalent bonds within the substrate molecule, whereas in other cases this lowering of the activation energy seems to take place because the enzyme holds the substrate molecules in a particular position that increases the …show more content…

If the enzymes become denatured the structure becomes disrupted and cannot return to its original shape.

One single enzyme molecule can react over and over (unless its denatured), however it is only capable of combining with a certain maximum number of substrate molecules per minute. This number is called the turnover number. Peroxidase has a very high turnover number and is capable of enzymatically destroying H2O2 (hydrogen peroxide) before it can do much damage, as it is [1]poisonous, corrosive and toxic to most living organisms, especially in too high a concentration. H2O2 is made in cells, it is a bi-product of cell metabolism. The catalase is used to remove H2O2 very quickly from cells by converting it into oxygen and water. The reaction occurs spontaneously, however the catalyst increases the rate dramatically.

2H2O2 2H2O + O2

Introduction: -------------

The aim of this investigation is to research how the concentration of substrate (H2O2 ) affects the rate of reaction of the enzyme catalase (yeast). Whether the rate increases or decreases with the different concentrations of hydrogen peroxide.

In the presence of a catalase, H2O2 willbreak down into water and oxygen (as shown in equation above). As the concentration of the substrate increases, the

Get Access