How Enzymes Function Notes
An enzyme reduces the energy necessary to start a chemical reaction. This means that the rate of
the reaction will increase.
Enzymes are not used up in the chemical reaction.
An enzyme reduces the activation energy.
An enzyme speeds up the conversion of substrate to product.
What happens to the amount of enzyme during a chemical reaction? It stays the same
Why is enzyme concentration not used to measure the rate of the enzyme-catalyzed reaction? The
concentration of an enzyme does not change. && An enzyme is not used up in a chemical
reaction.
What factors can affect the rate of a chemical reaction? The temperature of the reaction, how
much substrate is available, the pH in which the enzyme is active, how much enzyme is
available.
Enzymes speed up the rate of a chemical reaction.
Which substance is a chemical reaction will not change in concentration as the reaction
proceeds? The enzyme
What are the methods to measure the activity of an enzyme? Measuring how much substrate is
used, measuring how much product is made.
FALSE: To determine the activity of an enzyme, you can compare the concentration of the enzyme
before and after the chemical reaction.
Different types of enzymes may differ in optimal temperature and pH requirements, depending
upon where and how they function.
FALSE: When an enzyme speeds up a chemical reaction, it is consumed in the process.
The amount of enzyme does not change. Therefore, enzymes can be re-used and convert more
substrate to product.
Which of the following are true of an enzyme-catalyzed reaction? An enzyme speeds up the
conversion to product, enzymes are not used up in the chemical reaction, an enzyme reduces
the activation energy.
The activity of catalase can be measured as the rate of: Hydrogen peroxide breakdown, oxygen
formation.
How will you identify that the reaction is occurring? The production of oxygen will cause bubbling
in the test tube.
Hydrogen peroxide is broken down to produce water and oxygen with the help of the enzyme
catalase. Which of the following can be measured to determine the enzymatic activity? How much
water is produced, how much hydrogen peroxide is used, how much oxygen is produced.
Catalase activity can be detected by: observing the formation of oxygen bubbles.
, Catalase is the enzyme that catalyzes the reaction that breaks down hydrogen peroxide to
oxygen and water. What will happen as the reaction between catalase and hydrogen peroxide
proceeds? The amount of oxygen gas formation increases, the amount of hydrogen peroxide
decreases.
What is the purpose of preparing a tube with water and hydrogen peroxide? It’s a negative
control experiment.
In which tubes did hydrogen peroxide get broken down into water and oxygen? Catalase +
Hydrogen Peroxide
FALSE: When the enzyme catalase is mixed with water, oxygen bubbles are
produced. Which is required for the reaction to work? Hydrogen peroxide and
catalase solution
Which of the following combinations demonstrates that the enzyme catalase is specific for the
substrate hydrogen peroxide? Catalase + water
Increasing the concentration of enzyme at the beginning of the experiment results in more
substrate interacting with the enzyme per unit of time.
If enough substrate is present, adding more enzyme to a reaction mixture will increase the reate
of product formation.
If catalase is present in excess, reducing the amount of hydrogen peroxide in the reaction mix will
decrease the amount of oxygen gas formed.
What’s the purpose of preparing a tube with water and hydrogen peroxide? It allows for a
measurement with zero mL of catalase, it’s a negative control experiment.
In the concentration exercise, which test tube produced the highest column of bubbles after the
same amount of time? The one with most enzyme.
What will happen if the test tubes are left to react for an hour instead of 20 seconds? The bubbles
will burst, the bubbles will no longer be formed, all the tubes will have produced approximately
the same amount of bubbles.
If you have a constant amount of substrate, and add an increasing concentration of enzyme, what
will happen to the reaction rate? It will increase
Imagine three test tubes containing a constant amount of substrate but increasing amounts of
enzyme. After ten minutes, which tube will show the highest column of bubbles? The tube with
the largest enzyme concentration.
A graph constructed to show the relationship between enzyme concentration and enzyme activity
would have enzyme concentration plotted on the x-axis and bubble column height plotted on the
y-axis.
What are the reasons to measure the height of the bubble column exactly 20 seconds after
combining the catalase with the hydrogen peroxide? At shorter or longer times the difference in
enzyme concentration might not correlate to bubble height, the timing must be standardized
between the tubes.
An enzyme reduces the energy necessary to start a chemical reaction. This means that the rate of
the reaction will increase.
Enzymes are not used up in the chemical reaction.
An enzyme reduces the activation energy.
An enzyme speeds up the conversion of substrate to product.
What happens to the amount of enzyme during a chemical reaction? It stays the same
Why is enzyme concentration not used to measure the rate of the enzyme-catalyzed reaction? The
concentration of an enzyme does not change. && An enzyme is not used up in a chemical
reaction.
What factors can affect the rate of a chemical reaction? The temperature of the reaction, how
much substrate is available, the pH in which the enzyme is active, how much enzyme is
available.
Enzymes speed up the rate of a chemical reaction.
Which substance is a chemical reaction will not change in concentration as the reaction
proceeds? The enzyme
What are the methods to measure the activity of an enzyme? Measuring how much substrate is
used, measuring how much product is made.
FALSE: To determine the activity of an enzyme, you can compare the concentration of the enzyme
before and after the chemical reaction.
Different types of enzymes may differ in optimal temperature and pH requirements, depending
upon where and how they function.
FALSE: When an enzyme speeds up a chemical reaction, it is consumed in the process.
The amount of enzyme does not change. Therefore, enzymes can be re-used and convert more
substrate to product.
Which of the following are true of an enzyme-catalyzed reaction? An enzyme speeds up the
conversion to product, enzymes are not used up in the chemical reaction, an enzyme reduces
the activation energy.
The activity of catalase can be measured as the rate of: Hydrogen peroxide breakdown, oxygen
formation.
How will you identify that the reaction is occurring? The production of oxygen will cause bubbling
in the test tube.
Hydrogen peroxide is broken down to produce water and oxygen with the help of the enzyme
catalase. Which of the following can be measured to determine the enzymatic activity? How much
water is produced, how much hydrogen peroxide is used, how much oxygen is produced.
Catalase activity can be detected by: observing the formation of oxygen bubbles.
, Catalase is the enzyme that catalyzes the reaction that breaks down hydrogen peroxide to
oxygen and water. What will happen as the reaction between catalase and hydrogen peroxide
proceeds? The amount of oxygen gas formation increases, the amount of hydrogen peroxide
decreases.
What is the purpose of preparing a tube with water and hydrogen peroxide? It’s a negative
control experiment.
In which tubes did hydrogen peroxide get broken down into water and oxygen? Catalase +
Hydrogen Peroxide
FALSE: When the enzyme catalase is mixed with water, oxygen bubbles are
produced. Which is required for the reaction to work? Hydrogen peroxide and
catalase solution
Which of the following combinations demonstrates that the enzyme catalase is specific for the
substrate hydrogen peroxide? Catalase + water
Increasing the concentration of enzyme at the beginning of the experiment results in more
substrate interacting with the enzyme per unit of time.
If enough substrate is present, adding more enzyme to a reaction mixture will increase the reate
of product formation.
If catalase is present in excess, reducing the amount of hydrogen peroxide in the reaction mix will
decrease the amount of oxygen gas formed.
What’s the purpose of preparing a tube with water and hydrogen peroxide? It allows for a
measurement with zero mL of catalase, it’s a negative control experiment.
In the concentration exercise, which test tube produced the highest column of bubbles after the
same amount of time? The one with most enzyme.
What will happen if the test tubes are left to react for an hour instead of 20 seconds? The bubbles
will burst, the bubbles will no longer be formed, all the tubes will have produced approximately
the same amount of bubbles.
If you have a constant amount of substrate, and add an increasing concentration of enzyme, what
will happen to the reaction rate? It will increase
Imagine three test tubes containing a constant amount of substrate but increasing amounts of
enzyme. After ten minutes, which tube will show the highest column of bubbles? The tube with
the largest enzyme concentration.
A graph constructed to show the relationship between enzyme concentration and enzyme activity
would have enzyme concentration plotted on the x-axis and bubble column height plotted on the
y-axis.
What are the reasons to measure the height of the bubble column exactly 20 seconds after
combining the catalase with the hydrogen peroxide? At shorter or longer times the difference in
enzyme concentration might not correlate to bubble height, the timing must be standardized
between the tubes.
