Enzymes & Your Body

By Malinda Pires

Enzymes are Catalyst

• Enzymes speed up chemical reactions.•Animation Menu•Enzymes are catalyst to over 4000 biochemical reactions!

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http://en.wikipedia.org/wiki/File:GLO1_Homo_sapiens_small_fast.gif

Activation Energy

Enzymes work by lowering the activation energy needed to start a chemical reaction.

http://en.wikipedia.org/wiki/File:Activation_energy.svg

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Enzymes are Reusable

• Enzymes are reusable molecules found in living things.

• Animation Menu

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Classifying Enzymes• There are 4 major categories of macromolecules: carbohydrates, lipids, proteins, &

nucleic acids

• Most enzymes belong to the class of proteins.• However, there are a few catalytic RNA molecules.

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Naming Enzymes

• Take the name of the substrate the enzyme works on and add the suffix -ase

• Example: Lactose Lactase

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Enzyme Form and Function

• Lock & key Model: The shape of an enzyme allows it to do a specific job much like a lock and key.

• Specificity - Animation Menu

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Induced Fit Model• Enzymes can form to the shape of its

substrate.

http://en.wikipedia.org/wiki/File:Induced_fit_diagram.svg

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Denaturing Enzymes

• When an enzyme is denatured it is damaged.

• Denaturing changes the shape.

• Without the correct shape enzymes won’t function properly.

• HOW are enzymes denatured?– Temperature Animation Menu

– pH

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Enzyme Inhibitors

• Chemicals that prevent the enzyme from working.• Inhibitors decrease the enzyme reaction rate.

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http://en.wikipedia.org/wiki/File:Competitive_inhibition.svg

Enzyme Activators• Chemicals that help the enzyme work.• Activators increase the enzyme reaction rate.

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Activator

SubstrateBindingSite

ActiveSite

Enzymes are used all over your body!

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