Division Ave High School Ms. Foglia REGENTS...
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1 Division Ave High School Ms. Foglia REGENTS Biology Regents Biology 2009-2010 Enzymes: “Helper” Protein molecules Regents Biology Flow of energy through life Life is built on chemical reactions Regents Biology I. Chemical reactions of life Processes of life building molecules synthesis breaking down molecules digestion + + Regents Biology 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” + + enzyme enzyme We can’t live without enzymes! Regents Biology Examples synthesis digestion + enzyme enzyme Regents Biology II. 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 Oh, I get it! They end in -ase Regents Biology 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 enzyme substrate product active site Regents Biology III. It’s shape that matters! Lock & Key model shape of protein allows enzyme & substrate to fit specific enzyme for each specific reaction Regents Biology 1 2 3
Transcript of Division Ave High School Ms. Foglia REGENTS...
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Division Ave High School Ms. Foglia REGENTS Biology
Regents Biology 2009-2010
Enzymes: “Helper” Protein molecules
Regents Biology
Flow of energy through life § Life is built on chemical reactions
Regents Biology
I. Chemical reactions of life § Processes of life
u building molecules § synthesis
u breaking down molecules § digestion
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Regents Biology
Nothing works without enzymes! § How important are enzymes?
u all chemical reactions in living organisms require enzymes to work § building molecules
w synthesis enzymes
§ breaking down molecules w digestive enzymes
u enzymes speed up reactions § “catalysts”
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enzyme
enzyme We can’t live
without enzymes!
Regents Biology
Examples § synthesis
§ digestion
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+
enzyme
enzyme
Regents Biology
II. Enzymes are proteins § Each enzyme is the specific helper to
a specific reaction u each enzyme needs to be the right shape
for the job u enzymes are named for the reaction
they help § sucrase breaks down sucrose § proteases breakdown proteins § lipases breakdown lipids § DNA polymerase builds DNA
Oh, I get it! They end in -ase
Regents Biology
Enzymes aren’t used up § Enzymes are not changed by the reaction
u used only temporarily u re-used again for the same reaction with
other molecules u very little enzyme needed to help in many
reactions
enzyme
substrate product
active site
Regents Biology
III. It’s shape that matters! § Lock & Key model
u shape of protein allows enzyme & substrate to fit
u specific enzyme for each specific reaction
Regents Biology
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Division Ave High School Ms. Foglia REGENTS Biology
Regents Biology
Enzyme vocabulary § Enzyme
u helper protein molecule § Substrate
u molecule that enzymes work on § Products
u what the enzyme helps produce from the reaction
§ Active site u part of enzyme
that substrate molecule fits into
Regents Biology
V. What affects enzyme action § Correct protein structure
u correct order of amino acids u why? enzyme has to be right shape
§ Temperature u why? enzyme has to be right shape
§ pH (acids & bases) u why? enzyme has to be right shape
Regents Biology
Order of amino acids § Wrong order = wrong shape = can’t do its
job!
DNA
DNA
chain of amino acids
chain of amino acids
folded protein
folded protein
right shape!
wrong shape!
Regents Biology
VI. Temperature § Effect on rates of enzyme activity
u Optimum temperature § greatest number of collisions between
enzyme & substrate § human enzymes
w 35°- 40°C (body temp = 37°C) u Raise temperature (boiling)
§ denature protein = unfold = lose shape u Lower temperature T°
§ molecules move slower § fewer collisions between enzyme &
substrate Regents Biology
37°
Temperature
temperature re
actio
n ra
te
What’s happening
here?!
human enzymes
Regents Biology
How do cold-blooded creatures do it?
Regents Biology
VII. pH § Effect on rates of enzyme activity
u changes in pH changes protein shape u most human enzymes = pH 6-8
§ depends on where in body § pepsin (stomach) = pH 3 § trypsin (small intestines) = pH 8
Regents Biology
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pH
pH
reac
tion
rate
2 0 1 3 4 5 6 8 9 10
stomach pepsin
intestines trypsin
What’s happening
here?!
11 12 13 14
Regents Biology
Real Life Connections § What is lactose intolerance?
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Division Ave High School Ms. Foglia REGENTS Biology
Regents Biology
Why do we get uncomfortable symptoms with lactose intolerance?
Regents Biology 2009-2010
For enzymes… What matters?
SHAPE!
Regents Biology
Review Questions: § What is the function of enzymes?
§ What factors influence the functionality of enzymes?
§ Would amylase work on breaking down lipids? Why or why not?
Regents Biology 2009-2010
Let’s build some
Enzyme Models!
