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Enzymes are:
a) Carbohydrates
b) Lipids
c) Proteins
d) Nucleic acids
Enzymes act as:
a) Substrates
b) Catalysts
c) Products
d) Inhibitors
The region of the enzyme where the substrate binds is called the:
a) Active site
b) Inactive site
c) Binding site
d) Substrate site
Enzymes increase the rate of a chemical reaction by:
a) Decreasing the activation energy
b) Increasing the activation energy
c) Neutralizing the reactants
d) Creating new reactants
The specific molecule on which an enzyme acts is called the:
a) Inhibitor
b) Coenzyme
c) Substrate
d) Product
The term “enzyme-substrate complex” refers to:
a) The enzyme after catalyzing a reaction
b) The enzyme before catalyzing a reaction
c) The enzyme binding to an inhibitor
d) The enzyme binding to a substrate
Enzymes are highly specific, meaning that they:
a) Can catalyze multiple types of reactions
b) Can only catalyze one type of reaction
c) Are not affected by temperature
d) Are not affected by pH
The substance that is formed as a result of an enzyme-catalyzed reaction is called the:
a) Substrate
b) Inhibitor
c) Product
d) Coenzyme
Enzyme activity can be influenced by factors such as:
a) Temperature and pH
b) Substrate and product concentration
c) Pressure and light intensity
d) Volume and mass
The process in which an enzyme loses its shape and activity due to extreme temperature or pH is called:
a) Denaturation
b) Inhibition
c) Activation
d) Regulation
The substance that temporarily binds to the active site of an enzyme and prevents it from catalyzing a reaction is called a(n):
a) Substrate
b) Inhibitor
c) Activator
d) Coenzyme
Competitive inhibition occurs when:
a) The inhibitor binds to a different site than the active site
b) The inhibitor binds reversibly to the active site
c) The inhibitor permanently blocks the active site
d) The substrate concentration is very low
Non-competitive inhibition occurs when:
a) The inhibitor binds to a different site than the active site
b) The inhibitor binds reversibly to the active site
c) The inhibitor permanently blocks the active site
d) The substrate concentration is very low
An enzyme that requires a non-protein molecule to function properly is called a(n):
a) Allosteric enzyme
b) Coenzyme
c) Competitive enzyme
d) Inhibitory enzyme
The process by which an enzyme’s activity is regulated by molecules binding to its
allosteric site is called:
a) Competitive inhibition
b) Non-competitive inhibition
c) Allosteric regulation
d) Enzyme denaturation
The substance that binds to the allosteric site of an enzyme and enhances its activity is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
Enzyme activity is influenced by temperature because:
a) Higher temperatures increase the concentration of substrates
b) Higher temperatures increase the enzyme concentration
c) Enzymes become more stable at higher temperatures
d) Enzymes function optimally at specific temperatures
The specific pH at which an enzyme functions optimally is known as the:
a) Denaturation pH
b) Neutral pH
c) Optimal pH
d) Alkaline pH
The substance that is required by some enzymes to assist in catalysis is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The term “enzyme specificity” refers to:
a) The ability of an enzyme to catalyze multiple types of reactions
b) The ability of an enzyme to bind to any substrate
c) The ability of an enzyme to bind to a specific substrate
d) The ability of an enzyme to bind to any product
An enzyme-substrate complex is formed during the:
a) Activation of an enzyme
b) Inhibition of an enzyme
c) Binding of an enzyme to a coenzyme
d) Binding of an enzyme to a substrate
The enzyme’s function can be affected by changing its:
a) Shape
b) Size
c) Charge
d) Temperature
Which of the following factors does not affect enzyme activity?
a) Temperature
b) pH
c) Concentration of the product
d) Concentration of the substrate
The active site of an enzyme is:
a) The part of the enzyme that binds to the substrate
b) The part of the enzyme that binds to the product
c) The part of the enzyme that binds to the coenzyme
d) The part of the enzyme that binds to the inhibitor
Enzyme names usually end with the suffix:
a) -ase
b) -ose
c) -ite
d) -ide
Enzymes are essential for which of the following processes in living organisms?
a) Cell division
b) Photosynthesis
c) Muscle contraction
d) All of the above
Enzymes are classified under which category of biomolecules?
a) Carbohydrates
b) Lipids
c) Proteins
d) Nucleic acids
The process by which an enzyme loses its activity due to changes in temperature or pH is called:
a) Deactivation
b) Inhibition
c) Denaturation
d) Regulation
Enzymes are reusable, meaning that they:
a) Are destroyed after catalyzing a reaction
b) Can only be used once
c) Can be used multiple times
d) Can only catalyze one type of reaction
The substance that binds to the allosteric site of an enzyme and inhibits its activity is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The optimum pH for most enzymes in the human body is around:
a) pH 2
b) pH 7
c) pH 9
d) pH 12
An enzyme can be denatured by:
a) Extreme pH values
b) Moderate temperatures
c) Presence of coenzymes
d) Low substrate concentration
The substance that temporarily binds to the active site of an enzyme and allows it to catalyze a reaction is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The temperature at which an enzyme’s activity is at its highest is called the:
a) Optimal temperature
b) Denaturation temperature
c) Inhibitory temperature
d) Binding temperature
The pH at which an enzyme’s activity is at its highest is called the:
a) Optimal pH
b) Denaturation pH
c) Inhibitory pH
d) Binding pH
Enzymes are essential for the digestion of:
a) Carbohydrates
b) Lipids
c) Proteins
d) All of the above
An enzyme that requires a metal ion to function properly is called a(n):
a) Allosteric enzyme
b) Metalloenzyme
c) Competitive enzyme
d) Inhibitory enzyme
Which of the following factors does not affect enzyme activity?
a) Temperature
b) pH
c) Concentration of the product
d) Concentration of the substrate
The process by which an enzyme’s activity is regulated by molecules binding to its
allosteric site is called:
a) Competitive inhibition
b) Non-competitive inhibition
c) Allosteric regulation
d) Enzyme denaturation
The substance that binds to the allosteric site of an enzyme and enhances its activity is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
Enzyme activity is influenced by temperature because:
a) Higher temperatures increase the concentration of substrates
b) Higher temperatures increase the enzyme concentration
c) Enzymes become more stable at higher temperatures
d) Enzymes function optimally at specific temperatures
The specific pH at which an enzyme functions optimally is known as the:
a) Denaturation pH
b) Neutral pH
c) Optimal pH
d) Alkaline pH
The substance that is required by some enzymes to assist in catalysis is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The term “enzyme specificity” refers to:
a) The ability of an enzyme to catalyze multiple types of reactions
b) The ability of an enzyme to bind to any substrate
c) The ability of an enzyme to bind to a specific substrate
d) The ability of an enzyme to bind to any product
An enzyme-substrate complex is formed during the:
a) Activation of an enzyme
b) Inhibition of an enzyme
c) Binding of an enzyme to a coenzyme
d) Binding of an enzyme to a substrate
The enzyme’s function can be affected by changing its:
a) Shape
b) Size
c) Charge
d) Temperature
Which of the following factors does not affect enzyme activity?
a) Temperature
b) pH
c) Concentration of the product
d) Concentration of the substrate
The active site of an enzyme is:
a) The part of the enzyme that binds to the substrate
b) The part of the enzyme that binds to the product
c) The part of the enzyme that binds to the coenzyme
d) The part of the enzyme that binds to the inhibitor
Enzyme names usually end with the suffix:
a) -ase
b) -ose
c) -ite
d) -ide
Enzymes are essential for which of the following processes in living organisms?
a) Cell division
b) Photosynthesis
c) Muscle contraction
d) All of the above
Enzymes are classified under which category of biomolecules?
a) Carbohydrates
b) Lipids
c) Proteins
d) Nucleic acids
The process by which an enzyme loses its activity due to changes in temperature or pH is called:
a) Deactivation
b) Inhibition
c) Denaturation
d) Regulation
Enzymes are reusable, meaning that they:
a) Are destroyed after catalyzing a reaction
b) Can only be used once
c) Can be used multiple times
d) Can only catalyze one type of reaction
The substance that binds to the allosteric site of an enzyme and inhibits its activity is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The optimum pH for most enzymes in the human body is around:
a) pH 2
b) pH 7
c) pH 9
d) pH 12
An enzyme can be denatured by:
a) Extreme pH values
b) Moderate temperatures
c) Presence of coenzymes
d) Low substrate concentration
The substance that temporarily binds to the active site of an enzyme and allows it to catalyze a reaction is called a(n):
a) Inhibitor
b) Coenzyme
c) Activator
d) Substrate
The temperature at which an enzyme’s activity is at its highest is called the:
a) Optimal temperature
b) Denaturation temperature
c) Inhibitory temperature
d) Binding temperature
The pH at which an enzyme’s activity is at its highest is called the:
a) Optimal pH
b) Denaturation pH
c) Inhibitory pH
d) Binding pH
Enzymes are essential for the digestion of:
a) Carbohydrates
b) Lipids
c) Proteins
d) All of the above
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