Powerful Proteins

Enzymes 2

As well as allowing reactions to happen, enzymes also speed up chemical reactions in our bodies. These enzymes are also called catalysts. The definition of a catalyst is:

"A substance which when present in small amounts increases the rate of a chemical reaction or process but which is chemically unchanged by the reaction."

Some reactions in our bodies would happen too slowly in the absence of enzymes e.g. the waste product hydrogen peroxide would build up to toxic levels if we didn't have enzymes to speed up its breakdown into water and oxygen. Some enzymes increase reaction rates by a factor of one billion or more.

Enzymes are used in washing powder to break down dirt, in digestion to break down our food and in many other chemical reactions that occur in our bodies.

Yeast is added to hydrogen peroxide mixed with washing up liquid and food colouring. The hydrogen peroxidase enzyme in the yeast speeds up the breaking down of hydrogen peroxide to give oxygen and water. Oxygen bubbling through the soapy water gives masses of bubbles!

Hydrogen peroxide decomposes to give water and oxygen

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What are proteins? - Protein Building Blocks - Joining the Blocks - Polymers - Slimy polymers - Protein Folding - How to destroy a protein - Enzymes 1 - Enzymes 2 - Mobile Proteins - Protein Control Freaks - Proteins for Building - Making Proteins - Mutants - Protein Research

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Powerful Proteins

Enzymes 2

Next - Mobile Proteins

Previous - Enzymes 1

Back to the Topics List

What are proteins? - Protein Building Blocks - Joining the Blocks - Polymers - Slimy polymers - Protein Folding - How to destroy a protein - Enzymes 1 - Enzymes 2 - Mobile Proteins - Protein Control Freaks - Proteins for Building - Making Proteins - Mutants - Protein Research