8 5 Enzyme Activity 8 5 1 Enzyme

8. 5 Enzyme Activity 8. 5. 1 Enzyme Action LO: I understand how enzymes work.

The molecule that an enzyme acts upon is called the substrate. The substrate must fit into the active site on the enzyme before the reaction to take place. If the temperature is too high or the p. H is wrong, the enzyme will change shape. It becomes denatured and stops working. LO: I understand how enzymes work.

8. 5. 2 The Effect of p. H LO: I understand how p. H affects the activity of an enzyme.

Catalase is an enzyme that catalyses the breakdown of hydrogen peroxide in living cells. hydrogen peroxide oxygen + water Experiment: LO: I understand how p. H affects the activity of an enzyme.

The activity of the enzyme can be measured by counting the number of oxygen bubbles produced in 3 minutes Results: p. H 1 4 7 10 13 Number of Bubbles 0 6 28 63 45 LO: I understand how p. H affects the activity of an enzyme.

Graph: Number of O 2 bubbles Conclusion: p. H The activity of the enzyme increases with p. H to an optimum at p. H 10 and decreases thereafter. LO: I understand how p. H affects the activity of an enzyme.

8. 5. 3 The Effect of Temperature LO: I understand how temperature affects the activity of an enzyme.

Results: Number of O 2 bubbles Temperature (˚C) Conclusion: The activity increases with temperature to an optimum at 40˚C and thereafter decreases. LO: I understand how temperature affects the activity of an enzyme.