Transcript Which answer do you most agree with? Why?

Starter
1. All of the chemical reactions that take place
in an organism are referred to as m_______.
2. Is this a physical or chemical reaction? How
do you know?
3. Is this a physical or chemical reaction? How
do you know?
#1 - Enzymes are which of the
following molecules?
A.
B.
C.
D.
Carbohydrates
Lipids
Proteins
Nucleic Acids
#2 - Enzymes influence chemical
reactions in living systems by
A. providing the substrate required for the
reaction to occur
B. affecting the rate at which reactions occur
C. absorbing water released when polymers are
formed
D. combining with excess hydrogen to form
gaseous wastes
Enzyme Animation
• Why can an enzyme be reused?
• They are not changed or used up after a
reaction!
Q #5 - Which answer do you most
agree with? Why?
A. There was no reaction between the liver and
the vinegar because vinegar isn’t an enzyme.
B. There was no reaction because vinegar
cannot be broken down.
C. There was no reaction because vinegar
doesn’t break an enzyme down.
D. There was no reaction because the enzymes
in liver do not work to break down vinegar.
Enzymes work on a specific substrate!
What makes them specific?
Do they look the same?
Hydrogen peroxide
Vinegar
Lock and Key
Hypothesis
http://www.northland.cc.mn.us/biology/
Biology1111/animations/enzyme.html
Enzyme and
substrate fit
together
perfectly,
like a lock
and key!
http://highered.mcgrawhill.com/sites/0072495855/student_view0/chapter2/animation__how_enzy
mes_work.html
WHAT KINDS OF THINGS MIGHT
IMPACT HOW WELL AN ENZYME
WORKS?
Enzymes are Proteins…
• http://www.sumanasinc.com/webcontent/ani
mations/content/proteinstructure.html
HEAT
CHANGE IN pH
result in…
DENATURING AN ENZYME…
http://www.lewport.com/10712041113402793/lib/10712041113402793/Animations/Enzyme_activity
.html
DENATURING…
Changes the shape!
How?
-too much heat
-adding acid or base to change PH
How does a catalyst work?
A + B  AB
Activation energy = energy needed to start a chemical
reaction
What do enzymes do to activation energy?
#3 – What do enzymes do to activation
energy?
A. Increase it
B. Decrease it
C. Keep it the same
#4 – So, which do you think would happen faster?
A.
B.
C.
D.
Red line, because it requires more energy to get started.
Red line, because it requires less energy to get started.
Blue line, because it requires more energy to get started.
Blue line, because it requires less energy to get started.
Enzymes increase the rate of a reaction!
• They work by lowering the activation energy
needed to start the reaction!
Q #6 – If an enzyme is like a lock, what
would represent the active site?
A. The key, because it fits the lock
B. The combination, because it is used to open
the lock.
C. The key hole, because that’s where the key
fits.
D. The lock itself, since it’s the enzyme.
Q #7 – An enzyme that breaks down
protein will not act upon starch. This
fact is an indication that enzymes are
A.
B.
C.
D.
proteins
specific
catalysts
synthetic
WHAT ELSE?????
THINK ABOUT THE PAPERASE LAB!
Q #8 – At high temperatures, the rate
of enzyme action decreases because
the increased heat
A.
B.
C.
D.
changes the pH of the system
alters the active site of the enzyme
neutralizes the acids and bases in the system
increases the amount of the enzyme
Q #9 – Which environmental condition
would most likely have the LEAST effect
on the rate of an enzyme reaction?
A.
B.
C.
D.
the pH of the solution
the temperature of the solution
the amount of enzyme present
the amount of light present
THE REACTIONS WITHIN CELLS
GENERALLY INVOLVE THE BUILDING
OR THE BREAKDOWN OF COMPLEX
COMPOUNDS.
Synthesis and Decomposition
Anabolic reactions
Build compounds. (SYNTHESIS)
Energy is stored during these reactions.
Catabolic reactions
Break down compounds. (DECOMPOSITION)
Energy is released during these reactions.