Starter Activity: Write down as much as you can on a show me board about making proteins.

1. Brain Download Starter Activity: Write down as much as you can on a show me board about making proteins.

2. What are enzymes & what do they do? Your task… Research enzymes using page 14 and 15 of the revision guide. You will present your information using one piece of A4 paper to create a learning tool. You must include… Properties of enzymes. You should include… Enzyme specificity. You could include… Types of reactions: degradation and synthesis.

3. Section 5 Proteins and Enzymes

4. Proteins Learning Intention: Learn the functions of proteins. Success Criteria: State the functions of proteins

5. Watch and Listen • Protein Video Clip

6. Types of proteins • There are four types of proteins to consider. Types of proteins Structural Enzyme Hormones Antibodies Receptors

7. 1. Structural • Keratin is an example of a structural protein – it is strong an inelastic to protect hair. • Collagen- a strong, structural protein found in skin, tendons, ligaments and bones.

8. 2. Enzymes • Enzymes are biological catalysts that speed up a chemical reaction, while remaining unchanged. • Examples:- • Amylase is an enzyme found in the saliva. • Catalase found in every body cell. • Phosphorylase found in potatoes.

9. 3. Hormones • Hormones are chemical messengers that regulate processes in the body. • Examples:- • Insulin is a hormone to help control the concentration of blood glucose in the body. • Adrenaline is another example of a hormone that is used to regulate heart rate.

10. 4. Antibodies • Antibodies are Y shaped proteins in the immune system that help to fight infections. • Antibodies are produced by white blood cells after catching a virus. Eg Chicken pox, Influenza

11. 5. Receptors • These allow cells to recognise specific substances. • An examples of this is the receptors that liver cells have to allow them to recognise insulin.

12. Function of Proteins - Summary Proteins can be • Structural - e.g. Keratin • Enzymes - e.g. Amylase • Hormones - e.g. Insulin • Antibodies - to help the body’s immune system • Receptors – allows cells to recognise specific substances

13. Think Pair share • Discuss with your partner a way to remember the functions of proteins.

14. Proteins Learning Intention: Learn the functions of protein. Success Criteria: State the function of proteins.

15. Starter Activity: On a show me board, using no notes, write down the four functions of proteins.

16. Enzymes Learning Intention: Learn how enzymes work. Success Criteria: State that enzymes speed up chemical reactions. State why enzymes are reusable.

17. Catalyst Substances which speed up the rate of a chemical reaction. Take part but not changed by reaction. Can be used again and again. Lower the activation energy.

18. Catalyst Lower the energy input required for chemical reactions to take place.

19. What is an enzyme? • Enzymes are biological catalysts that speed up a chemical reaction, while remaining unchanged. • An enzyme is a chemical made of protein. • We find them in every living cell.

20. Watch and Listen • Enzymes Video Clip

21. What does an enzyme do? • You will now carry out an experiment to investigate what an enzyme does. • The enzyme you are using is called Amylase. Test Tube A: 5ml of Starch 2ml of Amylase Test Tube B: 5ml of Starch 2ml of Water

22. Food tests recap. • You may remember food tests from S2. • Iodine solution turns from brown to blue/black if starch is present. • Benedicts Solution turns from blue to orange/red if sugar (maltose) is present when heated.

23. Method Collect two test tubes. Label them A and B. Add 5ml starch to both test tubes. Add 2ml amylase to test tube A and 2ml water to test tube B. Take a few drops of sample A and place onto a dimple tile, test this with iodine solution and record the results. Repeat this for sample B. Take a few drops of sample A and place this into a test tube containing Benedicts solution, this will need to be heated to obtain your result. Repeat this for Sample B.

24. Results Copy and complete the table. Method : Now write a brief outline of the method you used in your own words. Remember to mention all the equipmentyou used and the volumes you measured.

25. Conclusion The enzyme _________ breaks down ______ into sugar (Maltose). COPY AND COMPLETE amylase starch Answers

26. Enzymes Summary • An enzyme is a biological catalyst made by all living cells. • They speed up the rate of reaction. • They are made of protein. • Life could not exist without them. • Amylase is an enzyme that breaks down starch to sugar.

27. Uses of enzymes

28. Enzymes Learning Intention: Learn how enzymes work. Success Criteria: 1. State that enzymes speed up chemical reactions. 2. State why enzymes are reusable.

29. Starter Activity: Tell your partner three things about an enzyme. Your teacher will ask you to share.

30. Starter Activity:

31. Starter Activity: Protein

32. Enzymes Learning Intention: Learn what specific means. Success Criteria: State that enzymes are specific.

33. Enzymes • Enzymes have an active site – this is where an enzyme reaction occurs. • The shape of the active site of enzyme molecules is complementary to a specific substrate.

34. Enzymes • Enzymes are specific This means each enzyme only works on one substrate (e.g. Amylase can only break down starch, nothing else)

35. Specificity

36. Lock and Key Hypothesis Each enzyme is specific and only works on one substrate- like a lock and key.

37. Enzyme Action • Enzyme action results in product(s) being formed. • This can be through a degradation reaction – when something is broken down into something smaller. • This can be through a synthesis reaction – when things are built up together to make something bigger.

38. Enzymes • You are going to carry out an investigation to find out if enzymes are specific. • Think about how you might do this. • Discuss your hypothesis with your lab partner

39. 2ml Hydrogen peroxide + 2ml catalase 2ml Hydrogen peroxide + 2ml amylase One Enzyme – One Reaction. • Copy and complete the diagram above. Make sure that you use a ruler!

40. Method • 1. Collect two test tubes. Label them A and B. • 2. Add 2ml hydrogen peroxide to each. • 3. Add 2ml catalase to test tube A and 2ml amylase to test tube B. • 4. Record the height of foam in each test tube.

41. Results

42. Conclusion • In test tube A what happened? • Why did this happen? • In test tube B what happened? • Why did this happen? • What do both these results show us?

43. Enzymes Learning Intention: Learn what specific means. Success Criteria: State that enzymes are specific.

44. Enzymes Learning Intention: Learn the effects that different conditions have on enzymes Success Criteria: State two conditions that affect enzyme activity. State what the term denatured means.

45. Starter

46. Starter A

47. Starter • Think about what might happen if the active site of an enzyme changed shape? • What might make it change shape?

48. Factors that affect enzymes • There are two factors that affect enzyme activity. • These are pH and temperature. • Each enzyme has its own set of optimum conditions. This means the conditions it works best at. • If these are altered, it affects the rate at which an enzyme works

49. Factors affecting enzymes heat pH normal denatured If the temperature and pH changes sufficiently beyond an enzyme’s optimum, the shape of the enzyme irreversibly changes. When this happens the enzyme is denatured. This affects the shape of the active site and means that the enzyme will no longer work.

50. Temperature All enzymes are made of protein, and proteins are denatured at high temperatures (above about 50°C). The rate of enzyme activity increases with temperature up to the optimum temperature. After that it decreases to zero as the enzyme is denatured.