1. 1 Enzymes

2. 2 What Are Enzymes? ProteinsMost enzymes are Proteins CatalystAct as Catalyst to accelerates a reaction Not permanentlyNot permanently changed in the process

3. 3Enzymes catalyzeAre specific for what they will catalyze ReusableAre Reusable aseMost end in –ase-Sucrase-Lactase-Maltase

4. 4 How do enzymes Work? weakening bonds lowers Enzymes work by weakening bonds which lowers activation energy

5. 5Enzymes Free Energy Progress of the reaction Reactants Products Free energy of activation Without Enzyme With Enzyme

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7. 7 Enzyme-Substrate Complex substance enzyme substrate The substance (reactant) an enzyme acts on is the substrate Enzyme Substrate Joins

8. 8 Active Site restricted region enzyme bindssubstrateA restricted region of an enzyme molecule which binds to the substrate. Enzyme Substrate Active Site

9. 9 Induced Fit shapeA change in the shape of an enzyme’s active site InducedInduced by the substrate

10. 10 Factors Affecting Enzyme Activity Temperature pH Cofactors & Coenzymes Inhibitors

11. 11 Temperature & pH High temperatures denature (Most like normal Body temperaturesHigh temperatures are the most dangerous reactions & denature enzymes (Most like normal Body temperatures) Most enzymes like near neutral pH (6 to 8) ionic saltsDenatured (unfolded) by ionic salts

12. 12 Cofactors and Coenzymes Inorganic substances (zinc, iron) vitamins enzymatic activityInorganic substances (zinc, iron) and vitamins (respectively) are sometimes needed for proper enzymatic activity. Example :Example : Iron hemoglobin oxygen Iron must be present in the protein, hemoglobin in order for it to pick up oxygen.

13. 13 Two examples of Enzyme Inhibitors a. Competitive inhibitors: resemble enzyme’s normal substrate competeactive site a. Competitive inhibitors: are chemicals that resemble an enzyme’s normal substrate and compete with it for the active site. Enzyme Competitive inhibitor Substrate

14. 14Inhibitors b.Noncompetitive inhibitors: do not enter the active sitebind to another part enzymeenzyme change its shape alters the active site Inhibitors that do not enter the active site, but bind to another part of the enzyme causing the enzyme to change its shape, which in turn alters the active site. Enzyme active site altered Noncompetitive Inhibitor Substrate

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