112022 Enzymes 1 What are enzymes 112022 Enzymes

1/1/2022 Enzymes 1

What are enzymes? 1/1/2022 • Enzymes are biological catalysts. • Catalysts increase the rate of chemical reactions. • They are not used up in the reaction. • Enzymes are proteins made of amino acid chains. • The chains are folded to form the active site. • The active site is where the substrate of the reaction binds with the enzyme. 2

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1/1/2022 What factors affect enzyme action? • Enzyme activity is affected by temperature and p. H. • High temperatures and the wrong p. H can change the shape of the active site to stop an enzyme working. • The change in shape is called denaturing. • Enzymes have an Optimal (“best”) temperature and p. H to work at. 4

1/1/2022 • Temperature speeds up the rate at which enzymes work. • After a certain temperature, enzymes become denatured and stop working. • Enzymes also have an Optimal (“best”) p. H to work at. 5

What we know about enzymes so far 1. What are enzymes also known as? 2. What do enzymes do to biological reactions? 3. What part of the enzyme carries out the reaction? 4. What are enzymes made of? 5. What is lost when an enzyme is denatured? 6. Write down two factors that can cause denaturing. 1/1/2022 Biological catalysts Speed them up The active site Protein The active site High Temperature or the wrong p. H. 1. Is it possible to destroy enzymes? Yes – by heating them. 6