Transcript 2.4 Reactions/Enzymes

2-4 Chemical Reactions & Enzymes
The Chemistry of Life,
Chemical reactions and
Enzymes 2-4
2-4 Chemical Reactions & Enzymes
Chemical reactions need help to get
started.
Ex: A fire needs a match to get it
started.
2-4 Chemical Reactions & Enzymes
The energy required to get a chemical
reaction STARTED
ACTIVATION ENERGY
Is called _________________
ACTIVATION
ENERGY
REACTANTS
PRODUCTS
2-4 Chemical Reactions & Enzymes
___________
CATALYSTS HELP CHEMICAL
REACTIONS HAPPEN FASTER
DECREASING the
Catalysts work by ___________
ACTIVATION ENERGY required to get a
chemical reaction started.
2-4 Chemical Reactions & Enzymes
IT’S LIKE PUSHING A
SNOWBALL UP A HILL
Once it gets to top . . .
it can roll back all by itself
2-4 Chemical Reactions & Enzymes
CATALYSTS in Living Things
In living systems
PROTEINS that
act as catalysts to
control chemical
reactions are called
ENZYMES
= _________
2-4 Chemical Reactions & Enzymes
PROTEINS CAN BE ENZYMES
ENZYME
ACTIVE
SITE
SUBSTRATE
ENZYME-SUBSTRATE
COMPLEX
ENZYME
Unchanged
& Reusable
PRODUCTS
2-4 Chemical Reactions & Enzymes
ENZYMES fit like
a lock and key
ONE KIND
SUBSTRATE
to only _________of
_________.
Enzymes are UNCHANGED by the
reaction and REUSABLE.
2-4 Chemical Reactions & Enzymes
FACTORS THAT AFFECT ENZYME
ACTIVITY
pH & __________
temperature
___
Conditions that are TOO ACIDIC
or TOO HOT cause proteins to
UNWIND or DENATURE
See a movie
2-4 Chemical Reactions & Enzymes
Denaturing changes the shape of the
ACTIVE SITE so enzyme
______________
SUBSTRATE
can’t bind to ____________
_______________
HOMEOSTASIS (keeping pH and
temperature constant) is important for
maintaining ENZYME FUNCTION
2-4 Chemical Reactions & Enzymes
-ASE
Many enzyme NAMES end in _____
and the beginning of the name tells
what it does
DNA Polymerase= “polymerizes”
joins monomers to make DNA
Protease=
breaks down proteins
ATP synthase= synthesizes ATP