Monthly Student Online Competition

Enzymes MDCAT MCQs with Answers

Welcome to the Enzymes MDCAT MCQs with Answers. In this post, we have shared Enzymes Multiple Choice Questions and Answers for PMC MDCAT 2024. Each question in MDCAT Chemistry offers a chance to enhance your knowledge regarding Enzymes MCQs in this MDCAT Online Test.

Enzymes are primarily composed of:
a) Carbohydrates
b) Lipids
c) Proteins
d) Nucleic acids

Answer
c

The part of an enzyme where substrate molecules bind is called the:
a) Active site
b) Allosteric site
c) Binding pocket
d) Regulatory site

Answer
a

Enzymes that catalyze the transfer of functional groups are known as:
a) Oxidoreductases
b) Transferases
c) Hydrolases
d) Ligases

Answer
b

Which of the following is a coenzyme that is involved in redox reactions?
a) Vitamin C
b) Vitamin D
c) Vitamin B12
d) Vitamin K

Answer
a

Enzymes that catalyze the breaking of peptide bonds are known as:
a) Lipases
b) Proteases
c) Amylases
d) Polymerases

Answer
b

The model describing enzyme action that suggests the enzyme changes its shape to accommodate the substrate is:
a) Lock and key model
b) Induced fit model
c) Enzyme-substrate complex model
d) Competitive inhibition model

Answer
b

Enzymes that catalyze the addition of a phosphate group to a molecule are called:
a) Phosphatases
b) Kinases
c) Ligases
d) Hydrolases

Answer
b

Which of the following factors does NOT affect enzyme activity?
a) Temperature
b) pH
c) Substrate concentration
d) Pressure

Answer
d

The rate of an enzyme-catalyzed reaction can be increased by:
a) Decreasing substrate concentration
b) Increasing enzyme concentration
c) Increasing temperature beyond the optimum
d) Increasing pH beyond the optimum

Answer
b

Inhibition where the inhibitor binds to the enzyme at a different site than the active site is known as:
a) Competitive inhibition
b) Non-competitive inhibition
c) Uncompetitive inhibition
d) Irreversible inhibition

Answer
b

The efficiency of an enzyme can be measured by its:
a) Km value
b) Vmax value
c) Turnover number
d) Binding affinity

Answer
c

The enzyme-substrate complex forms at the:
a) Active site
b) Allosteric site
c) Regulatory site
d) Binding site

Answer
a

Enzymes that are involved in DNA replication and repair are known as:
a) Polymerases
b) Ligases
c) Nucleases
d) Isomerases

Answer
a

The concept that an enzyme undergoes a change in shape upon substrate binding is called:
a) Lock and key hypothesis
b) Induced fit hypothesis
c) Enzyme-substrate specificity
d) Enzyme catalysis

Answer
b

Which type of enzyme inhibition cannot be overcome by increasing substrate concentration?
a) Competitive inhibition
b) Non-competitive inhibition
c) Uncompetitive inhibition
d) Allosteric inhibition

Answer
b

Enzymes that catalyze reactions where two molecules are joined together are known as:
a) Hydrolases
b) Ligases
c) Lyases
d) Isomerases

Answer
b

Which of the following is a common cofactor required by many enzymes?
a) Calcium
b) Sodium
c) Magnesium
d) Potassium

Answer
c

Enzymes that cleave bonds by adding water are called:
a) Oxidoreductases
b) Transferases
c) Hydrolases
d) Lyases

Answer
c

The term used to describe the maximum rate of an enzyme-catalyzed reaction is:
a) Km
b) Vmax
c) Turnover number
d) Michaelis constant

Answer
b

The amount of substrate required to reach half of the maximum reaction velocity is known as:
a) Vmax
b) Km
c) Turnover number
d) Enzyme efficiency

Answer
b

Enzymes that catalyze the rearrangement of molecular structures are called:
a) Isomerases
b) Ligases
c) Lyases
d) Transferases

Answer
a

Which enzyme is responsible for the breakdown of hydrogen peroxide into water and oxygen?
a) Catalase
b) Amylase
c) Lipase
d) Protease

Answer
a

Enzymes that catalyze the removal of a group of atoms from a substrate are known as:
a) Hydrolases
b) Lyases
c) Ligases
d) Transferases

Answer
b

Enzymes that require metal ions for their activity are called:
a) Apoenzymes
b) Holoenzymes
c) Cofactors
d) Coenzymes

Answer
b

The concept that enzyme activity can be regulated by molecules that bind to sites other than the active site is known as:
a) Allosteric regulation
b) Competitive inhibition
c) Non-competitive inhibition
d) Substrate-level regulation

Answer
a

Enzymes that catalyze reactions by adding or removing a carbon dioxide molecule are called:
a) Lyases
b) Hydrolases
c) Ligases
d) Transferases

Answer
a

Which type of inhibition involves the binding of an inhibitor to the active site of an enzyme?
a) Competitive inhibition
b) Non-competitive inhibition
c) Uncompetitive inhibition
d) Allosteric inhibition

Answer
a

What type of enzyme activity is characterized by the enzyme functioning best at a specific pH level?
a) Temperature dependence
b) pH dependence
c) Substrate concentration dependence
d) Enzyme concentration dependence

Answer
b

Enzymes that facilitate the formation of peptide bonds are known as:
a) Proteases
b) Peptidases
c) Ligases
d) Polymerases

Answer
c

The decrease in enzyme activity due to high temperatures is called:
a) Denaturation
b) Inhibition
c) Activation
d) Stabilization

Answer
a

What is the term used to describe the overall process where an enzyme binds to its substrate and converts it into product?
a) Enzyme activation
b) Enzyme inhibition
c) Enzyme catalysis
d) Enzyme degradation

Answer
c

Enzymes that add or remove hydrogen atoms during a reaction are known as:
a) Oxidoreductases
b) Transferases
c) Hydrolases
d) Lyases

Answer
a

The presence of a coenzyme in an enzyme’s active site is crucial for:
a) Increasing the reaction rate
b) Stabilizing the enzyme structure
c) Providing additional chemical reactivity
d) Binding the substrate

Answer
c

What type of enzyme activity is reduced by the presence of a competitive inhibitor?
a) Vmax
b) Km
c) Turnover number
d) Catalytic efficiency

Answer
b

The enzyme that helps in the synthesis of RNA from a DNA template is called:
a) DNA polymerase
b) RNA polymerase
c) Ligase
d) Helicase

Answer
b

Enzymes that are inactive until a specific molecule binds to them are called:
a) Proenzymes
b) Holoenzymes
c) Apoenzymes
d) Cofactors

Answer
a

The mechanism where an enzyme changes its conformation to facilitate substrate binding is:
a) Lock and key model
b) Induced fit model
c) Competitive model
d) Allosteric model

Answer
b

Enzymes that facilitate the formation of a new bond between two molecules using energy from ATP are known as:
a) Ligases
b) Hydrolases
c) Transferases
d) Isomerases

Answer
a

Which of the following statements about enzymes is incorrect?
a) Enzymes are highly specific for their substrates
b) Enzymes are consumed in the reactions they catalyze
c) Enzymes lower the activation energy of reactions
d) Enzymes can be regulated by various factors

Answer
b

The overall process of enzyme catalysis includes:
a) Substrate binding
b) Formation of the enzyme-substrate complex
c) Conversion of substrate to product
d) All of the above

Answer
d

If you are interested to enhance your knowledge regarding PhysicsChemistryComputer, and Biology please click on the link of each category, you will be redirected to dedicated website for each category.

Was this article helpful?
YesNo
See Also  Relation Between Linear And Angular Variables MDCAT MCQs with Answers
Facebook
Twitter
LinkedIn
WhatsApp
Pinterest
Telegram
Picture of YFP

YFP

YFP empower the youth with the ability to nurture their communication and leadership skills at a common national platform resulting in greater self-confidence and personal growth.

Leave a Reply

Your email address will not be published. Required fields are marked *