1. WJEC GCE BIOLOGY Inhibitors and Enzyme Action S TATION 2 G RAPHS TO SHOW THE EFFECTS OF I NHIBITORS ON E NZYME A CTION N AVIGATE YOUR WAY THOUGH ALL OF THE ANIMATIONS CLICKING ON EXPLANATIONS EACH TIME T HEN COMPLETE THE WORKSHEET

2. WJEC GCE BIOLOGY Inhibitors and Enzyme Action N ORMAL ENZYME REACTION RATE 1 Rate of reaction Substrate concentration

3. WJEC GCE BIOLOGY Inhibitors and Enzyme Action Explaination Forward N ORMAL ENZYME REACTION RATE

4. WJEC GCE BIOLOGY Inhibitors and Enzyme Action N ORMAL ENZYME REACTION RATE 1 2 Rate of reaction Substrate concentration

5. WJEC GCE BIOLOGY Inhibitors and Enzyme Action ExplanationClose Every active site is saturated. The rate of the reaction is at its highest. Forward N ORMAL ENZYME REACTION RATE

6. WJEC GCE BIOLOGY Inhibitors and Enzyme Action 1 2 3 Rate of reaction Substrate concentration N ORMAL ENZYME REACTION RATE

7. WJEC GCE BIOLOGY Inhibitors and Enzyme Action Forward ExampleClose Every active site is saturated, so there is no increase in the rate of reaction. N ORMAL ENZYME REACTION RATE

8. WJEC GCE BIOLOGY Inhibitors and Enzyme Action 1 2 3 Competitive Inhibitor Revise Rate of reaction Substrate concentration N ORMAL ENZYME REACTION RATE

9. WJEC GCE BIOLOGY Inhibitors and Enzyme Action C OMPETITIVE INHIBITOR REACTION RATE 1 2 Non-competitive Inhibitor Revise Rate of reaction Substrate concentration

10. WJEC GCE BIOLOGY Inhibitors and Enzyme Action C OMPETITIVE I NHIBITOR EXAMPLE : A N IMPORTANT ENZYME IN RESPIRATION IS SUCCINATE DEHYDROGENASE. I TS SUBSTRATE IS SUCCINATE, WHICH IS CONVERTED INTO FUMARATE Forward CloseExplanation A competitive inhibitor binds to the enzyme’s active site, and slows down the process. Succinate Succinate dehydrogenase Malonate

11. WJEC GCE BIOLOGY Inhibitors and Enzyme Action ExplanationClose The substrate will soon find an active site. The effect of a competitive inhibitor is to slow down the process. Forward C OMPETITIVE I NHIBITOR EXAMPLE : A N IMPORTANT ENZYME IN RESPIRATION IS SUCCINATE DEHYDROGENASE. I TS SUBSTRATE IS SUCCINATE, WHICH IS CONVERTED INTO FUMARATE Succinate Succinate dehydrogenase Malonate

12. WJEC GCE BIOLOGY Inhibitors and Enzyme Action N ON COMPETITIVE INHIBITOR 1 2 Rate of reaction Re-Revise Substrate concentration

13. WJEC GCE BIOLOGY Inhibitors and Enzyme Action Close N ON COMPETITIVE E XAMPLE : C OPPER S ULPHATE AND CATALASE Explanation The shape of the active site changes because the non- competitive inhibitor has bound to an allosteric site; so preventing an enzyme- substrate complex from forming = less products formed Forward Hydrogen peroxide Catalase CuSO 4

14. WJEC GCE BIOLOGY Inhibitors and Enzyme Action CloseExplanation The reaction rate cannot reach the same point because the non- competitive inhibitors have changed the shape of some of the active sites. Forward N ON COMPETITIVE E XAMPLE : C OPPER S ULPHATE AND CATALASE Hydrogen peroxide Catalase CuSO 4