1. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

2. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

3. Enzyme structure
Proteins that work as a catalyst. Speed up chemical reactions without being altered themselves.

4. Enzyme structure
Enzymes only catalyse one reaction Thousands of reactions take place in a cell Majority need to be catalysed. Organisms produce thousands of enzymes Enzymes are specific

5. Specificity
Enzymes have an active site Specific to a substrate Only that substrate can fit Cannot catalyse other reactions

6. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

7. Three stages Substrate bins to active site of enzyme.
2. Substrates change into different chemical substances
3. These products separate from the active site, leaving it vacant for substrates to bind again

8. Collisions
Random movement of substrates and enzymes Means there are collisions Only bind together if they are aligned exactly Usually dissolved in water to allow more collisions

9. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

10. Denaturation
Structure can be irreversibly altered by certain conditions. Active site shape changes – substrate can no longer bind

11. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

12. Your task
Each of you will be investigating the following factors affecting the rate of reaction of enzymes.
Temperature pH
Concentration of substrate

13. Your task – How is the rate of reaction of enzymes affected by the different factors.
pH – Joshua, Po Lam, Chun To, Hon
Temp – Megan, Angel, Candy
Conc. – Brian, Arthur, Vincent, Kelvin
We will be using
Hydrogen peroxide (substrate)
Yeast (enzyme)
You need to design an experiment (using the criteria) that we will do on Tuesday next week.
Use this lesson to sort out what lab orders you need (these need to go to David by the end of Friday) and write a draft

14. Enzymes
Describe the structure of an enzyme State the three stages of enzyme activity Explain the factors that affect enzyme activity Describe how enzymes can be denatured Explain the use of immobilised enzymes with reference to lactose free milk

15. Enzymes can be commercially used
Immobilised enzymes
Enzymes can be commercially used

16. Immobilised enzymes
Usually immobilised Attach enzymes to another material or into aggregations Enzyme movement is restricted What are the advantages? Extension: How is lactose-free milk produced using enzymes?