Honors Biology - Enzymes

Download Honors Biology - Enzymes

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<ul><li>1.Enzymes: Helper Protein molecules</li></ul> <p>2. Flow of energy through life Life is built on chemical reactions 3. Chemical reactions of life Processes of life building molecules synthesis+ breaking down molecules digestion + 4. Nothing works without enzymes! How important are enzymes? all chemical reactions in living organisms require enzymes to work enzyme building molecules synthesis enzymes + breaking down molecules enzymeWe cant live digestive enzymeswithout enzymes!+ enzymes speed up reactions catalysts 5. Examples synthesisenzyme + digestion +enzyme 6. A THREE SLIDE INTERMISSIONThese relate to your GuidedReading Notes 7. Endergonic vs. exergonic reactionsexergonicendergonic- energy released- energy invested- digestion- synthesis- break down molecules - build molecules 8. Reducing Activation energy Catalysts reducing the amount of energy tostart a reaction uncatalyzed reaction Pheeewthat takes a lotless energy! catalyzed reaction NEW activation energyreactant product 9. Catalysts So whats a cell got to do to reduce activation energy? get help! chemical help ENZYMESCall in theENZYMES! 10. AND WE ARE BACKThe next slide is #6 11. Enzymes are proteins Each enzyme is the specific helper toa specific reaction each enzyme needs to be the right shape for the job enzymes are named for the reaction they helpOh, I get it! sucrase breaks down sucrose They endin -ase proteases breakdown proteins lipases breakdown lipids DNA polymerase builds DNA 12. Enzymes arent used up Enzymes are not changed by the reaction used only temporarily re-used again for the same reaction with other molecules very little enzyme needed to help in many reactions substrateproduct active siteenzyme 13. Its shape that matters! Lock &amp; Key model shape of proteinallows enzyme &amp;substrate to fit specific enzymefor each specificreaction 14. 213 15. Enzyme vocabulary Enzyme helper protein molecule Substrate molecule that enzymes work on Products what the enzyme helps produce fromthe reaction Active site part of enzymethat substratemolecule fits into 16. What affects enzyme action Correct protein structure correct order of amino acids why? enzyme has to be right shape Temperature why? enzyme has to be right shape pH (acids &amp; bases) why? enzyme has to be right shape 17. Order of amino acids Wrong order = wrong shape = cant do its job!folded chain of proteinamino acidsDNAright shape!foldedprotein chain ofamino acidswrong shape!DNA 18. Temperature Effect on rates of enzyme activity Optimum temperature greatest number of collisions between enzyme &amp; substrate human enzymes 35- 40C (body temp = 37C) Raise temperature (boiling) denature protein = unfold = lose shape Lower temperature T molecules move slower fewer collisions between enzyme &amp; substrate 19. Temperaturehuman Whats enzymes happeninghere?! reaction rate37 temperature 20. pH Effect on rates of enzyme activity changes in pH changes protein shape most human enzymes = pH 6-8 depends on where in body pepsin (stomach) = pH 3 trypsin (small intestines) = pH 8 21. pHstomachintestines Whats happening pepsintrypsinhere?!reaction rate0 12 34 56 7 8 910 11 12 13 14pH 22. For enzymesWhat matters?SHAPE! </p>