AIM: What are enzymes and why are they important?

DN: What are proteins? What are the building blocks of proteins? Give some examples of proteins.

What role do enzymes play in our bodies?

A + B C

Enzymes are proteins that speed

up chemical reactions

Let’s Review Chemical Reactions:

• A + B Cor

• C A + B

Raw Materials Products

What Reaction is this?

A + B AB + H2ODehydration SynthesisEnzyme

If an enzyme is added to the reaction, then it will speed up the reaction.

In other words, we will produce AB more quickly.

What is a Catalyst?

Any substance that speeds up a chemical reaction without itself being changed.

An enzyme is called an organic catalyst

Why are enzymes called organic catalysts?

They are PROTEINS that speed up chemical reactions!!

What are some important reactions that enzymes need to speed up?

Digestion Synthesis

Photosynthesis Cell Respiration

What are Substrates and Active Sites?

AB

A + B AB

Substrates- are the reactants that bind to the enzymeActive Site- is the place on the enzyme where thesubstrates bind

Think of enzymes and substrates as a lock and key

Substrate

Enzyme Active Site

Enzyme-Substrate Complex

Is formed when the substrate is bound to the enzyme

Enzyme Substrate

Enzyme-substrate specificityEnzymes are SPECIFIC (in

shape) for the SUBSTRATES they attach to, just like a lock

and key.

How do enzymes work?

A + B AB ENZYME

AB

Enzymes bind to the reactants so the chemicalreaction can take place

What do you think determines the shape of enzymes?

Enzyme

1)The sequence (order) of amino acids in a protein determine its shape

2) The shape of a protein determines its activity

WHAT CHANGES?

A-B + H2O A + BEnzyme

What reaction is this?Hydrolysis

• The enzyme doesn’t change, it can be reused• The substrate changes

• Hydrolysis- substrate is broken down (ex: carbohydrate to glucose molecules)

• Dehydration Synthesis- the substrate is made bigger (glucose molecules made into a starch)

Some common enzymes

PROTEIN AMINO ACIDSprotease

Hydrolysis

Can you ID the substrate, product, enzyme, active site, & enzyme substrate

complex?

SubstrateProduct

Enzyme

Active Site

Enzyme – Substrate Complex