ENZYME ACTIVITY
How to interpret enzyme graphs
(NEXT
SLIDE)
Reading Graphs
Substrate
Which graph shows the amount of
substrate going to zero faster?
Substrate

Time (sec)
Time (sec)
So…
Substrate
Nope, the amount of substrate gets to zero
in less time in the OTHER graph.
Substrate

Time (sec)
Time (sec)
So…
Substrate
YES!! The amount of substrate gets to
zero in less time in this graph.
Substrate

Time (sec)
Time (sec)
So…
Substrate
Which enzyme works FASTER?
Substrate

Time (sec)
Time (sec)
So…
Substrate
Nope, not this one. The faster the enzyme
works, the faster the substrate will
decrease.
Substrate

Time (sec)
Time (sec)
So…
Substrate
YES!! This enzyme works faster because
the substrate decreases faster!!
Substrate

Time (sec)
Time (sec)
What do you think can affect the
speed of an enzyme?
TEMPERATURE
pH
AMOUNT OF
LIGHT
What do you think can affect the
speed of an enzyme?
TEMPERATURE

RIGHT!! Changing
the pH of the
reaction can affect
the speed of an
enzyme.

ANYTHING ELSE?
pH
AMOUNT OF
LIGHT
What do you think can affect the
speed of an enzyme?
TEMPERATURE
pH
AMOUNT OF
LIGHT

RIGHT!! Changing
the temperature of
the reaction can
ALSO affect the
speed of an
enzyme.
What do you think can affect the
speed of an enzyme?
TEMPERATURE

RIGHT!! Changing
the temperature of
the reaction can
affect the speed of
an enzyme.

ANYTHING ELSE?
pH
AMOUNT OF
LIGHT
What do you think can affect the
speed of an enzyme?
TEMPERATURE
pH
AMOUNT OF
LIGHT

RIGHT!! Changing
the pH of the
reaction can ALSO
affect the speed of
an enzyme.
What do you think can affect the
speed of an enzyme?
TEMPERATURE

Sorry, most
enzymes are NOT
affected by the
amount of light…

Pick again
pH
AMOUNT OF
LIGHT
Factors affecting enzyme speed

We can make a graph of enzyme speed at
different temperatures.
Graph of ENZYME SPEED
What should go on the X axis?
Speed of enzyme
Temperature (C)
Graph of ENZYME SPEED
Nope, the speed of the enzyme is what we
are MEASURING,it should go on the Y axis.
Speed of enzyme
Temperature (C)
Graph of ENZYME SPEED
Amount of substrate
What should go on the Y axis?
(HINT: This is what we are
MEASURING)
Speed of enzyme
RIGHT! Temperature should go on the
X axis.
0
10
20
30
40
Temperature (C)
50
60
Graph of ENZYME SPEED
Amount of substrate
Speed of enzyme
0
10
What should go on the Y axis?
(HINT: This is what we are
MEASURING)
•We’re not measuring the
amount of substrate this
time.
20
30
40
Temperature ( C)
50
60
Graph of ENZYME SPEED
FAST
Speed of enzyme
RIGHT!!
The speed of enzyme
should go on the Y axis.
REMEMBER!! The enzyme is working FASTER
As you go UP the Y axis.
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase is found in saliva.
Click on the red button that is
approximately at body
temperature
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase is found in saliva.
5C is close to freezing.
TOO COLD!!
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase is found in saliva.
22C is close to room
temperature.
TOO COLD!!
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase is found in saliva.
55C is 131F.
TOO HOT!!
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase is found in saliva.
37C is body temperature.
RIGHT!! Amylase will work best
at about 37C because it is
normally found in your mouth
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
Speed of enzyme
FAST
Amylase works slowly
At very low temperatures
Because it is not close
To body temperature
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
Speed of enzyme
FAST
Amylase will work
Faster as it gets
Closer to body
Temperature.
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
FAST
Speed of enzyme
Amylase will
work fastest
at body
Temperature.
The temperature where
Amylase works BEST is
called the OPTIMUM
TEMPERATURE
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
As the temperature gets too hot,
Amylase doesn’t work as well.
Speed of enzyme
FAST
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
Click on the
OPTIMUM TEMPERATURE
Speed of enzyme
FAST
SLOW
0
10
20
30
40
Temperature ( C)
50
60
Let’s GRAPH!!
Click on the
OPTIMUM TEMPERATURE
Speed of enzyme
FAST
RIGHT!!
SLOW
0
10
20
30
40
Temperature ( C)
50
60
What is the optimum
temperature for this enzyme?
Speed of enzyme
FAST
10C
20C
30C
SLOW
0
10
20
30
40
50
Temperature ( C)
60
What is the optimum
temperature for this enzyme?
FAST
Speed of enzyme
REMEMBER: The OPTIMUM is
the temperature the enzyme
works fastest at.
10C
20C
30C
SLOW
0
10
20
30
40
50
Temperature ( C)
60
What is the optimum
temperature for this enzyme?
FAST
Speed of enzyme
REMEMBER: The OPTIMUM is
the temperature the enzyme
works fastest at.
10C
20C
30C
SLOW
0
10
20
30
40
50
Temperature ( C)
60
Right!!
What is the optimum pH for this
enzyme?
Speed of enzyme
FAST
9
10
11
SLOW
0
2
4
pH
6
8
10
12
What is the optimum pH for this
enzyme?
FAST
Speed of enzyme
Look closely…
9
10
11
SLOW
0
2
4
pH
6
8
10
12
What is the optimum pH for this
enzyme?
FAST
Speed of enzyme
Look closely…
9
10
11
SLOW
0
2
4
pH
6
8
10
12
Right!!
What is the optimum
temperature for this enzyme?
Speed of enzyme
FAST
20C
63C
48C
SLOW
20
30
40
50
60
70
Temperature ( C)
80
What is the optimum
temperature for this enzyme?
Speed of enzyme
FAST
20C
63C
48C
SLOW
20
30
40
50
60
70
Temperature ( C)
80
What is the optimum
temperature for this enzyme?
Speed of enzyme
FAST
20C
63C
48C
SLOW
20
30
40
50
60
70
Temperature ( C)
80
Right!!
What temperature does the
enzyme work best at?
Temperature =
Temperature =
Temperature =
25C
30C
35C
Time
At 25C
Time
Time
At 30C
At 35C
REMEMBER: the faster the
substrate decreases, the faster the
enzyme is working
Temperature =
Temperature =
Temperature =
25C
30C
35C
Time
At 25C
Time
Time
At 30C
At 35C
REMEMBER: the faster the
substrate decreases, the faster the
enzyme is working
Temperature =
Temperature =
Temperature =
25C
30C
35C
Time
At 25C
Time
Time
At 30C
At 35C
TO SHOW HOW WELL YOU
UNDERSTOOD, COMPLETE
THIS SHORT QUIZ
QUIZ - QUESTION 1

Where in your body is the amylase
enzyme found?
SALIVA
LIVER
STOMACH
QUIZ - QUESTION 1

Where in your body is the amylase
enzyme found?
SALIVA
LIVER
STOMACH
QUIZ - QUESTION 1

Where in your body is the amylase
enzyme found?
SALIVA
LIVER
STOMACH
Right!!
QUIZ - QUESTION 2

Click on the CATALYST in this reaction:
SUGAR
STARCH
AMYLASE
QUIZ - QUESTION 2

REMEMBER: The catalyst performs the
reaction, but isn’t used up
SUGAR
STARCH
AMYLASE
QUIZ - QUESTION 2

REMEMBER: The catalyst performs the
reaction, but isn’t used up
SUGAR
STARCH
AMYLASE
Right!!
QUIZ - QUESTION 3

Click on the substrate that is most likely to
react with the enzyme below:
STARCH
PROTEIN
LIPID
QUIZ - QUESTION 3

REMEMBER: The subtrate that fits into a
protein will be the one that reacts with it.
STARCH
PROTEIN
LIPID
QUIZ - QUESTION 3

REMEMBER: The subtrate that fits into a
protein will be the one that reacts with it.
STARCH
PROTEIN
LIPID
Right!!
PROTEIN
QUIZ - QUESTION 4

What is the most likely name of the
enzyme in question 3 that reacts with
protein?
PROTEINOSE
PROTEINATION
PROTEINZYME
PROTEINASE
QUIZ - QUESTION 4

NOPE: sugars end in -OSE, not enzymes
(sucrose, lactose, glucose)
PROTEINOSE
PROTEINATION
PROTEINZYME
PROTEINASE
QUIZ - QUESTION 4

NOPE: think about “lactase” and
“amylase”
PROTEINOSE
PROTEINATION
PROTEINZYME
PROTEINASE
QUIZ - QUESTION 4

NOPE: think about “lactase” and
“amylase”
PROTEINOSE
PROTEINATION
PROTEINZYME
PROTEINASE
Right!!
QUIZ - QUESTION 5
Click on the part of the graph that shows
the OPTIMAL temperature for this enzyme
Enzyme Activity

Temperature (C)
QUIZ - QUESTION 5
REMEMBER: the OPTIMAL temperature
for an enzyme is the temperature where
the enzyme works BEST (highest activity)
Enzyme Activity

Temperature (C)
Right!!
QUIZ - QUESTION 6

Click on the graph that shows the optimum
pH for this enzyme.
pH = 5.0
pH = 7.0
pH = 3.0
Time
Time
Time
QUIZ - QUESTION 6

REMEMBER: Substrate decreases in
LESS time if the enzyme works faster
pH = 5.0
pH = 7.0
pH = 3.0
Time
Time
Time
QUIZ - QUESTION 6

REMEMBER: Substrate decreases in
LESS time if the enzyme works faster
pH = 5.0
pH = 7.0
pH = 3.0
Time
Time
Time
Right!!
Right!!
You have successfully completed
the enzyme powerpoint.