Enzymes!
Enzymes are biologic catalysts that are made of protein and help speed up chemical
reactions in the body. Without enzymes, many of the important processes of life
could not happen.

Enzymes are very specific in their functions. Each enzyme only has one
reaction that it can help with.

Enzymes are not changed when they perform their function. This means
that the same enzyme molecule can be used over and over again.

Some enzymes may even be used repeatedly on the same set of small
molecules to build a long chain of repeating subunits.

As with all proteins the shape of an enzyme determines its function. An
organism has the ability to make many different enzymes, and each enzyme
has one particular function.

Sometimes, high temperatures or extreme pH values may affect the shape
of an enzyme molecule. This process, called denaturing, will also make the
enzyme less effective, possibly even useless.
Why enzymes?
How did the enzyme help speed up the synthesis of maltose from two glucose
molecules?
It held it in the right position so that the bonds could form more quickly than if you
wait for them to hit in the right spot.
Specificness
Why can’t the green enzyme help with the digestion of the double sugar?
Because it is not the right shape, each enzyme is only able to help with one reaction.
Reusing Enzymes
Enzymes can be reused to link multiple building blocks together to build a long chain.
What are some examples of these polymers (long chains of molecules)?
DNA, starch, proteins.
Denaturing
Enzymes denature under extreme heat or pH, why does this make the enzyme unable
to work? Can it be reversed?
The enzyme changes its shape and the reactants no longer fit it cannot be used again.
Website: http://www.lewport.wnyric.org/jwanamaker/animations/Enzyme%20activity.html
Dehydration Synthesis
Step 1: Two small building blocks come to the
Step 2: Once on the enzyme’s active site a
Step 3: The product of the reaction is released
enzyme.
bond forms between the building blocks
and the enzyme is ready to be used again.
Hydrolysis - Digestion
Step 1: A dimmer (two molecules linked
Step 2: Once on the dimmer the bond
Step 3: The products of the reaction are
together) comes to the enzyme.
between the two molecules is broken.
released and the enzyme can be used again.
Enzymes end in the suffix – ase
Examples:
Substrate
Enzyme
Product(s)
Maltase
Maltose
Glucose + Glucose
Lipase
Lipid
1 glycerol and 3 fatty acids
Protease
Protein
Amino Acids
Amylase
Starch
Simple Sugars
Polymerase
Nucleotides
DNA
Factors that Affect Enzyme Action
1. Substrate Concentration
Enzyme action will increase if substrate concentration is increased until all enzyme molecules
are in action and then the rate levels off.
2. Temperature
Enzymes are very sensitive to temperature
Cold temperatures – slow down reactions
Optimum temperature- when the enzyme works most efficiently (fastest)
High Temperatures – Stops the reaction and changes the molecular shape of the enzyme.
When the shape of the enzyme is changed it is denatured and it never works again!
3. pH
Most enzymes work best at a pH of 7 (neutral). However, some can work in an
extremely acidic environment, for example your stomach. If pH changes drastically,
the enzyme action decreases.