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1. Enzyme Notes
2. Enzyme lab pre & post questions (2 stamps)
3. Catalase lab data collection and rough draft
4. Notes on Enzyme Activity
1. What indicator is used to test for the
disaccharide sucrose?
2. When sucrose undergoes hydrolysis, what
are the products of the reaction?
3. What kind of molecule speeds up the
hydrolysis of sucrose?
4. What indicator can be used to detect the
presence of the monomers produced?
1. What indicator is used to test for the
disaccharide sucrose? NONE!
2. When sucrose undergoes hydrolysis, what
are the products of the reaction?
Glucose and Fructose (monosaccharides)
3. What kind of molecule speeds up the
hydrolysis of sucrose? Enzymes
4. What indicator can be used to detect the
presence of the monomers produced?
Benedicts (with heat)
Section Outline
Section 2-4
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2–4
Chemical Reactions and
Enzymes
A.
B.
C.
D.
Chemical Reactions
Energy in Reactions
1.
2.
Energy Changes
Activation Energy
Enzymes
Enzyme Action
1. The Enzyme-Substrate Complex
2. Regulation of Enzyme Activity
Anatomy of a Chemical
Equation
Reactant
+
Reactant
“Reacts with”
“and”, etc.
Product
YIELDS
(“To produce”)
+
“and”
Product
Example
Sucrose
+
Water
“Reacts with”
“and”, etc.
Enzyme
YIELDS
(“To produce”)
Glucose
+
“and”
Fructose
Effect of Enzymes
Section 2-4
Reaction pathway
without enzyme
Activation energy
without enzyme
Reactants
Reaction pathway
with enzyme
Activation
energy
with enzyme
Products
ENZYME
SUBSTRATE
Lactase
Lactose
Sucrase
Sucrose
Amylase
Bromelin
Starch
Pectin
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Make a Hypothesis
Draw the experimental setup
Label beakers (DO NOT WRITE ON WHITE PART)
Label test tubes (DO NOT WRITE ON WHITE PART)
Label pipettes
Come to the front to get your chemicals
After adding the Benedicts to the test tubes,
finger vortex for 30 seconds before putting in
water bath.
 Return
any unused solutions to
the stock bottles up front
 Rinse all test tubes and place
them upside down to dry
 Return evertyhing to the white
basket.
You cut yourself – mom pours hydrogen
peroxide on the cut.
What happens? It Bubbles
Why? There is a chemical reaction
(and an enzyme)
Equation:
H2O2
Catalase
H2O
(l)
+
O2 (g)
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You will be using a jumbo test tube instead of
a cup
Pour your peroxide in s l o w l y! Otherwise it
will overflow and you will not get a reading.
DO NOT POUR YOUR REACTION WASTE DOWN
THE SINK. It is raw chicken liver and it will
smell bad for months. There is a waste
container up front for disposal.
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Average your times for each 30 second interval
Get averages of other groups that had the same
amount of catalase as you.
Average all those times for each 30 second
interval together.
Make a rough draft graph of your now much
more accurate data
Divide your graph into 2 sections (where the
graph slope changes drastically)
HW) Find the rate of the first section in units of
degrees Celcius / second
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4a. Do your increase in rate calculations
support your hypothesis concerning enzyme
concentration? Explain how you calculated
the rate.
4b. Why did the temperature
decrease/plateau after reaching a peak?
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Enzyme Activity depends on factors such as
◦Temperature
◦pH
Enzyme works
fastest
Enzyme
Denatures
(breaks down)
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What is the effect of increased catalase
concentration on the breakdown of peroxide
measured by increasing temperature of
reaction?
Figure 2-19 Chemical Reactions
Section 2-4
Energy-Absorbing Reaction
Energy-Releasing Reaction
Activation
energy
Products
Activation energy
Reactants
Reactants
Products
Figure 2-19 Chemical Reactions
Section 2-4
Energy-Absorbing Reaction
Energy-Releasing Reaction
Activation
energy
Products
Activation energy
Reactants
Reactants
Products