Enzymes: “The Molecules of Life” s1
Enzymes:
“The Molecules of Life”
s1
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EnzymesEnzymes•Are proteins•Are specific
for what they will catalyzecatalyze
•Are ReusableReusable•End in –asease
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How do enzymes Work?How do enzymes Work?
Enzymes work by weakening weakening bondsbonds which which lowers lowers activation activation energyenergy
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EnzymesEnzymes
FreeEnergy
Progress of the reaction
Reactants
Products
Free energy of activationFree energy of activation
Without Enzyme
With Enzyme
______________ to get a chemical reaction _______________
= ________________________
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ACTIVATION ENERGY
REACTANTSPRODUCTS
ACTIVATIONENERGY
Energy requiredSTARTED
___________ HELP CHEMICAL REACTIONS _______________
Catalysts work by ____________ the___________________________to get a chemical reaction started.
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DECREASING
CATALYSTS
ACTIVATION ENERGY required
HAPPEN FASTER
PROTEINS CAN BE ENZYMES
SUBSTRATE
ENZYME-SUBSTRATE COMPLEX
PRODUCTSENZYMEUnchanged& Reusable
ENZYME
Image modified from: http://www.biologie.uni-hamburg.de/b-online/library/cat-removed/enzyme_.gifArrow: http://www.gifanimations.com/action/ImageDisplay/1/2/11/next
ACTIVESITE
SubstrateSubstrate
• The substancesubstance (reactant) an enzymeenzyme acts on.
Enzyme
Substrate
Active SiteActive Site
• A restricted regionrestricted region of an enzymeenzyme molecule which bindsbinds to the substratesubstrate.
Enzyme
Active Site
Substrate
Click HERE to learn more about enzymes
ENZYMES _____ like a _______________
to only _________of _________.
Enzymes are ___________ by thereaction and ___________
LOCK AND KEY
REUSABLEUNCHANGED
FIT
ONE KIND SUBSTRATE
http://www.grand-illusions.com/images/articles/toyshop/trick_lock/mainimage.jpg
Lock and Key
FACTORS THAT AFFECT ENZYME ACTIVITY
__________ & ______________
Conditions that are TOO ACIDIC
or TOO HOT cause proteins to________ or _________
pH temperature
UNWIND DENATURE
http://www.desktopfotos.de/Downloads/melt_cd.jpg http://www.nealbrownstudio.com/adm/photo/163_nb_fried_egg.jpg
See a movieChoose narrated
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Denaturing _______ the _______ of the ______________ so enzyme ______________ to ____________
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_______________ (keeping pH and temperature constant) is ______________ for maintaining ____________________
HOMEOSTASIS
changes shapeACTIVE SITE
CAN’T BIND SUBSTRATE
IMPORTANTENZYME FUNCTION
37°
Temperature
temperature
reacti
on
rate
What’s happening here?!
Concept Check:
Label the following on the diagram below:
enzyme, active site, substrate
For enzymes…What matters?
SHAPE!