Warm up (Engage)
-Make a “T” chart and write “Break” on left sideAnd “Build/assemble” on the right side.Using the pictures below identify which one
breaks things and which ones build or assemble.
Scissors
Glue Tape
Chain Saw Stapler
Knife
What happens to the food after we eat them?
Video Reflection
• Where is fat digested?• Where is carbohydrate digested?• Where is protein digested?
• What is the name of the structure that aids in digestion for all these Biomolecules?
Enzymes, who are you?
This is what enzymes do …
How does it happen?
Hydrogen peroxide (H2O2)
Liver= host many enzymes such as Catalase
Catalase turns H2O2 into…
H2O2 + Catalase (in liver) = H20 +O2
What is H20? What is 02?So where is bubbling coming from?
Enzymes• Enzymes are proteins that act as biological catalysts. • The function of a catalysts is to speed up chemical
reactions that take place in cells. • Enzymes act by lowering the activation energies in a
chemical reaction.
ENZYMES• Proteins that regulate chemical
reactions (ex. digestion). • Catalyst-speeds up chemical
reaction but is not consumed in the reaction.
• Enzymes are very specific to who they attach: Works like a lock and key:– Substrate– Active site
How enzyme works
http://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Induced_fit_diagram.svg/450px-Induced_fit_diagram.svg.png
They can also do this…
What’s the diff erence?
How do enzymes work?
• The Enzyme-Substrate Complex– Enzymes provide a site where reactants can be
brought together to react (active sites). – The reactants that binds to the active site is called
substrates.
Video summary of what enzymes do functionally
Click here
Enzymes
• Enzymes can break apart a chemical molecule. OR
• Put them together.
Chemically this is what enzymes do…• Catalyst-speeds up chemical reaction but is
not consumed in the reaction. – They Kick off the chemical reaction by Lowering
the Activation energy. • Activation energy: The energy required to
complete a reaction.
Reaction pathwaywithout enzyme Activation energy
without enzyme
Activationenergywith enzymeReaction pathway
with enzyme
Reactants
Products
A
B
Shape matters!
Enzymes are proteins that have an active site some where on the molecule where others molecules can land and react. Pretizel
http://today.slac.stanford.edu/images/2010/algae-enzyme.jpg
Active site
Think of enzyme as Pac man
http://3.bp.blogspot.com/_Q8OAp1ni8ys/S_d18_SKKkI/AAAAAAAAAHg/973QvIZGTYE/s1600/pacman.PNG
EXIT TICKET
1. Enzymes belong to which biomolecule?2. What does a catalysts do to a chemical
reaction?3. T/F Any substrate can bind to the active site
of an enzyme. 4. T/F Enzymes can only break apart a
substrate. 5. T/F All proteins are enzymes.
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What Affects Enzyme Activity?
• Three factors:1. Environmental Conditions
2. Cofactors and Coenzymes
3. Enzyme Inhibitors
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1. Environmental Conditions
1. Extreme Temperature are the most dangerous- high temps may denature (unfold) the enzyme.
2. pH (most like 6 - 8 pH near neutral)
3. Ionic concentration (salt ions)
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2. Cofactors and Coenzymes
• Inorganic substances (zinc, iron) and vitamins (respectively) are sometimes need for proper enzymatic activity.
• Example:Iron must be present in the
quaternary structure - hemoglobin in order for it to pick up oxygen.
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Two examples of Enzyme Inhibitors
a. Competitive inhibitors: are chemicals that resemble an enzyme’s normal substrate and compete with it for the active site.
Enzyme
Competitive inhibitor
Substrate
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Inhibitorsb. Noncompetitive inhibitors:
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
NoncompetitiveInhibitor
Substrate