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“Enzyme” music video http://casesblog.blogspot.com/2009/04/music-video-enzyme-what-are-you-doing.html. Goal 2.04: Enzymes “Helper” Protein molecules. +. +. Recall?. Processes of life making molecules synthesis breaking down molecules digestion. ?. ?. enzyme. +. enzyme. +.
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“Enzyme” music video http://casesblog.blogspot.com/2009/04/music-video-enzyme-what-are-you-doing.html Goal 2.04: Enzymes “Helper” Protein molecules
+ + Recall? • Processes of life • making molecules • synthesis • breaking down molecules • digestion ? ?
enzyme + enzyme + Nothing works without enzymes! • How important are enzymes? • ALL chemical reactions in living organisms require enzymes to work • building molecules • synthesis enzymes • breaking down molecules • digestive enzymes • enzymes speed up reactions • “catalysts” ? ?
How Do Enzymes Work? Enzymes reduce the activation energy! ? ACTIVATION ENERGY = energy required to cause the reaction to occur. ACTIVATION ENERGY = energy required to cause the reaction to occur. ENERGY ENERGY TIME TIME
Enzymes are PROTEINS! • Each enzyme is the specific helper to a specific reaction • each enzyme needs to be the right shape for the job • enzymes are named for the reaction they help • sucrase breaks down sucrose • proteases breakdown proteins • lipases breakdown lipids • DNA polymerase builds DNA SPECIFICITY! I get it! They end in -ase
Enzymes aren’t 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 How enzymes work: http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html
Substrate = substance to be changed Products = substances produced Enzyme-Substrate Complex = enzyme and molecules temporarily joined Active Site = location on enzyme where substrate fits Is this a digestive or synthesizing enzyme? Enzyme = reusable protein that can make or break molecules
It’s shape that matters! • Lock & Key model • shape of protein allows enzyme & substrate to fit • specific enzyme for each specific reaction Substrate Enzyme
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Lactose Intolerant? • You need some LACTASE! • Lactose = sugar found in milk • Lactase = enzyme that breaks down lactose.
QuickLab: Building an enzyme model. Prep VL1 and Do Virtual Lab 1 (potato only):Catalase Action by Living Tissue What Affects Catalase Activity? http://bioweb.wku.edu/courses/Biol114/enzyme/enzyme2.asp
Regulation of Enzymes • 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 & bases) • why? enzyme has to be right shape ? ? ?
Effect on rates of enzyme activityEnzyme Concentration • increase the amount of enzyme = increases how fast the reaction happens • more enzymes = more frequently they collide with substrate ?
Enzyme concentration Why does the reaction rate level off? Enzyme action uses up substrate! Reactions increase… reaction rate As concentration increases… amount of enzyme
Substrate Concentration • Effect on rates of enzyme activity • as increase amount of substrate = increases how fast the reaction happens • more substrate = more frequently they collide with enzyme ?
Substrate concentration Reactions increase… reaction rate As concentration increases… amount of substrate
Temperature • Effect on rates of enzyme activity • Optimumtemperature • greatest number of collisions between enzyme & substrate • human enzymes = • 35°- 40°C (body temp = 37°C) • Too HOT! • denatureprotein = unfold = lose shape • Too COLD! • molecules move s l o w e r • decrease collisions ?
Optimum Temperature What is the optimum temperature for this enzyme? Explain what is happening? 37oC (98.6oF) Temperature Enzyme Activity
pHAffects Enzymes! • Effect on rates of enzyme activity • pH changes protein shape • most human enzymes = pH 6-8 • depends on where in body • pepsin (stomach) = pH 3 • trypsin (small intestines) = pH 8 • buffers adjust pH to keep it normal ? ?
pH stomachpepsin intestinestrypsin reaction rate 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 pH
SHAPE! For enzymes…What matters? Enzymeshttp://www.phschool.com/science/biology_place/labbench/lab2/concepts.html
Any Questions? Assignment: Coach Book L11Study Island Lesson 3c Captain Enzyme! www.andysmithart.com