enzymes. what are enzymes? enzymes are proteins. an enzyme is a catalyst. they speed up reactions...
TRANSCRIPT
EnzymesEnzymes
What are Enzymes?What are Enzymes?
Enzymes are proteins.
An enzyme is a catalyst. They speed up reactions that take place in your body.
Enzymes are proteins.
An enzyme is a catalyst. They speed up reactions that take place in your body.
What are Enzymes?What are Enzymes? Enzymes are very
specific. Will only catalyze
one specific reaction. Usually named for
the reaction they catalyze.
They are reusable and not permanently changed.
Enzymes are very specific.
Will only catalyze one specific reaction.
Usually named for the reaction they catalyze.
They are reusable and not permanently changed.
How Do Enzymes Work?How Do Enzymes Work?
Catalysts work by lowering the activation energy (the energy needed to start a chemical reaction) of the reaction=huge effect on the time it takes a reaction to happen!
Catalysts work by lowering the activation energy (the energy needed to start a chemical reaction) of the reaction=huge effect on the time it takes a reaction to happen!
5
6
FreeEnergy
Progress of the reaction
Reactants
Products
Free energy of activationFree energy of activation
Without Enzyme
With Enzyme
Enzymes lower the activation energy!Enzymes lower the activation energy!
The Enzyme-Substrate Complex
The Enzyme-Substrate Complex
Substrate: The substance (reactant) an enzyme works on.
Substrate: The substance (reactant) an enzyme works on.
EnzymeSubstrateJoins
The Enzyme-Substrate Complex
The Enzyme-Substrate Complex
ACTIVE SITE: The part of the enzyme where the substrate binds to it.
ACTIVE SITE: The part of the enzyme where the substrate binds to it.
EnzymeSubstrate
Active Site
They fit together like puzzle pieces!
They fit together like puzzle pieces!
VideoVideo
http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html
The Enzyme-Substrate Complex
The Enzyme-Substrate Complex
How does it work?1.Substrates come in close
physical contact at the active site.
2.Substrates bind together and are made into products.
3.The products are released and the cycle starts over.
How does it work?1.Substrates come in close
physical contact at the active site.
2.Substrates bind together and are made into products.
3.The products are released and the cycle starts over.
http://www.youtube.com/watch?v=CZD5xsOKres
How Enzymes are NamedHow Enzymes are Named All enzymes end in –ASE!! The enzyme often sounds like the
substrate it breaks down.
All enzymes end in –ASE!! The enzyme often sounds like the
substrate it breaks down.
SUBSTRATE ENZYME
Lactose
Maltose
Sucrose
Lipids
Cellulose
Polysaccharides Amylase
Sucrase
Maltase
Lactase
Cellulase
Lipase
Things that Regulate Enzymes
Things that Regulate Enzymes
Temperature High temperatures can change
the structure of it. pH
Extremely high or low pH values can make it not work.
Temperature High temperatures can change
the structure of it. pH
Extremely high or low pH values can make it not work.
Review-Write these on the back of your notes.
Review-Write these on the back of your notes.
1. Enzymes area. Lipidsb. Carbohydratesc. Proteinsd. Nucleic Acids
2. Which binds to the active site of an enzyme?a. waterb. productc. another enzymed. substrate
Review (cont.)Review (cont.)
3. An enzyme can only bind one reactant (substrate) at a time.a. Trueb. False
4. An enzyme speeds up a chemical reaction in the cell, but can only be used once.a. Trueb. False
Review (cont.)Review (cont.)
5. Which substrate would this enzyme work on?
Review (cont.)Review (cont.)
6. Catalystsa. slow down a reaction.b. make enzymes.c. speed up a reaction.d. are nucleic acids.
7. What’s another name for enzyme substrate complex?a. Fast and slowb. Lock and keyc. Reactant and product d. Apple and pear
Review (cont.)Review (cont.)
8. Label:
Active Site
Enzyme
Substrate
Review (cont.)Review (cont.)
9. What happens in a chemical reaction after the substrate binds to the enzyme at the active site? a. The formation of a new product.b. The formation of another enzyme.c. Nothing happens.d. The enzyme is damaged.