Factors Affecting Enzymes Gr C: Explain how 2 factors affect the enzyme activity. Gr B: Investigate each factor using a practical. Gr A: Plot a graph to evidence how different factors affect enzymes. Starter Key Factors Give a definition of what an enzyme is. Bonus point for people who give examples of different enzymes, and for people who produce an illustration. Temperature pH of solution Concentration of enzymes An enzyme is a biological catalyst made of proteins, they are produced in living organisms and are used to speed up chemical reaction by breaking down substrates. Catalase, Amylase, Pepsin, lipase + 

Enzyme Recap

Do enzymes get “used up”?

If the iodine turns black then the reaction hasn’t finished Results table Copy out the results table as shown below, include the results for the tests already done. Temperature 30s 60s 90s 120s 150s 180s 210s 10oC Black Clear 30oC 50oC 70oC 90oC If the iodine turns black then the reaction hasn’t finished If the iodine remains the same colour then the chemical reaction has finished and the starch has been converted to glucose by the amylase.

Method Step 1) Place 2 drops of iodine in each dimple within the spotting tile. Step 2) Select a starch solution to test, and add three drops of amylase to the starch solution. Whilst doing this, start a stop watch. Step 3) Using a new pipette, collect one drop of starch and amylase solution every 30 seconds and place it in one of the dripping trays. Step 4) Does the solution turn black or not? If the iodine turns black then amylase hasn’t completely broken up the starch, if the iodine stays the same colour then the amylase has completed its reaction.

Results table Copy out the results table as shown below, include the results for the tests already done. Temperature 30s 60s 90s 120s 150s 180s 210s 10oC Black Clear 30oC 50oC 70oC 90oC Learning Activity Time Plot a graph to show how the temperature affects the enzyme’s rate of reaction (time). Temperature

Conclusion Write a conclusion for the graph below. The conclusion needs to have a discussion of how temperature affects the enzyme’s rate of reaction. Refer to the title of both axis. Discuss about each sections of the graph. (Section 1: 0oC -30oC, Section 2: 30oC-40oC, Section 3: 40oC-60oC)

Denaturing When an enzyme is at its optimum temperature, it means that the enzyme is under perfect conditions for the chemical reaction. Therefore, it works at its optimum rate. When an enzyme is placed in conditions above its optimum temperature then it starts to denature. When an enzyme denatures the heat causes it to change shape, this then alters the active site meaning it can no longer fit with the substrate. This is shown in the diagram above. This isn’t reversible, one an enzyme denatures, it will not be able to function again.

10mins Success criteria: Learning Activity Create an explanation of the term denature. Use diagrams, illustrations, and graphs to support your explanation. 10mins Success criteria: Definition of the terms denature and optimum. Explanation of how enzymes become denatured. Illustration of an enzyme working at its optimum temperature. Illustration of an enzyme which has been denatured with an explanation of why it isn’t working.

Learning Activity Learning Activity Extension Gr C: Explain that enzymes have optimum pH’s. Gr B: Complete grade C and use the information below to evidence your point. Learning Activity Extension Gr C: Explain that enzymes have optimum temperatures. Gr B: Complete grade C and use the information below to evidence your point. Gr A: Include an explanation of denaturing.

Factors Affecting Enzymes Gr C: Explain how 2 factors affect the enzyme activity. Gr B: Investigate each factor using a practical. Gr A: Plot a graph to evidence how different factors affect enzymes. Starter Key Factors Give a definition of what an enzyme is. Bonus point for people who give examples of different enzymes, and for people who produce an illustration. Temperature pH of solution Concentration of enzymes An enzyme is a biological catalyst made of proteins, they are produced in living organisms and are used to speed up chemical reaction by breaking down substrates. Catalase, Amylase, Pepsin, lipase + 

A substance that lowers the effectiveness of an enzyme. The area of an enzyme where the substrate joins. 37ºC (body temperature) The process where the active site changes shape. Catalase, Amylase, Lipase, Phosphorylase, Lock and Key A substance that increases the effectiveness of an enzyme Learning Activity A protein that functions as biological catalyst. Click on a colour and think, What is the question? What is the question? Anabolic reaction pH and temperature Respiration