Enzymes

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Enzymes
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What are Enzymes?

• Enzymes are proteins.
• An enzyme is a catalyst. They speed up reactions
  that take place in your body.

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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.

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How Do Enzymes Work?

• Catalysts work by lowering the activation energy
  (the energy needed to start a chemical reaction)
  of the reactionhuge effect on the time it takes
  a reaction to happen!

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Enzymes lower the activation energy!
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The Enzyme-Substrate Complex

• Substrate The substance (reactant) an enzyme
  works on.

Joins
Substrate
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The Enzyme-Substrate Complex

• ACTIVE SITE The part of the enzyme where the
  substrate binds to it.

Active Site
Substrate
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They fit together like puzzle pieces!
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Video
http//highered.mcgraw-hill.com/sites/0072495855/s
tudent_view0/chapter2/animation__how_enzymes_work.
html
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The Enzyme-Substrate Complex

• How does it work?
• Substrates come in close physical contact at the
  active site.
• Substrates bind together and are made into
  products.
• The products are released and the cycle starts
  over.

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http//www.youtube.com/watch?vCZD5xsOKres
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How Enzymes are Named

• All enzymes end in ASE!!
• The enzyme often sounds like the substrate it
  breaks down.

SUBSTRATE ENZYME






Lactose
Lactase
Maltose
Maltase
Sucrose
Sucrase
Lipids
Lipase
Cellulose
Cellulase
Polysaccharides
Amylase
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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.

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Review-Write these on the back of your notes.

• Enzymes are
• Lipids
• Carbohydrates
• Proteins
• Nucleic Acids

• Which binds to the active site of an enzyme?
• water
• product
• another enzyme
• substrate

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Review (cont.)

• An enzyme can only bind one reactant (substrate)
  at a time.
• True
• False

• An enzyme speeds up a chemical reaction in the
  cell, but can only be used once.
• True
• False

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Review (cont.)

• Which substrate would this enzyme work on?

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Review (cont.)

• Catalysts
• slow down a reaction.
• make enzymes.
• speed up a reaction.
• are nucleic acids.

• Whats another name for enzyme substrate complex?
• Fast and slow
• Lock and key
• Reactant and product
• Apple and pear

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Review (cont.)

1. Label

Substrate
Active Site
Enzyme
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Review (cont.)

• What happens in a chemical reaction after the
  substrate binds to the enzyme at the active site?
  
• The formation of a new product.
• The formation of another enzyme.
• Nothing happens.
• The enzyme is damaged.