49 Questions
Which type of enzyme catalyzes redox reactions?
Oxidoreductases
What is the function of amylase?
Digests starch
Which enzyme catalyzes the digestion of lactose?
Lactase
What is the main function of transferases?
Transfer of functional group between 2 substrates
Which subclass of isomerases involves the alteration of the spatial arrangement of atoms in a molecule?
Mutases
What is the function of ligases in terms of molecule combination?
Combine molecules through aid of ATP
What is the main characteristic of enzymes as catalysts?
True catalyst and do not alter equilibrium constant
What is the role of cofactors in enzyme structure?
Small molecules required for enzymatic activity
How do enzymes increase reaction rates?
By decreasing the activation energy
'Lock-and-Key' model proposed by Emil Fischer implies that:
Enzyme and substrate interact with specific matching shapes at the active site
What is the main function of induced-fit model in enzyme-substrate interaction?
Enzymes are flexible and their shapes can be modified by binding with a substrate
What does acid/base catalysis involve?
Proton (H+) transfer, which is common in biochemical reactions
What is demonstrated in the reaction between an ester and carboxylate group?
Entropy reduction by restraining motion of molecules for reaction to proceed
What does metal ion catalysis involve?
Bound metal cofactor orienting substrate for reaction or stabilizing charged transition states
What does binding energy (GB) facilitate in enzyme-substrate interaction?
Facilitates formation of transition state by reducing activation energy
Enzymes can alter the equilibrium constant of a reaction.
False
Ligases are a subclass of isomerases.
False
Enzymes are not highly regulated and their rate of activity cannot adjust to the condition of the cell.
False
Enzymes are not highly specific and do not selectively recognize proper substrate over other molecules.
False
All enzymes are made up of simple proteins only.
False
Prosthetic groups are not required for the biological function of enzymes.
False
Enzymes increase reaction rate by increasing the activation energy.
False
The lock-and-key model implies that the enzyme and the substrate interact by means of short-range forces that require close contact.
True
The induced-fit model states that enzymes are inflexible and the shapes of active sites cannot be modified by binding with a substrate.
False
Entropy reduction is not demonstrated in the reaction between an ester and carboxylate group.
False
Acid/base catalysis does not involve proton transfer in biochemical reactions.
False
Metal ion catalysis does not involve the orientation of the substrate for the reaction or stabilization of charged transition states.
False
Enzymes are biological catalysts that increase the rate of reaction by factors more than a million times without being used up.
True
Enzymes lower the activation energy by providing an alternate pathway for chemical reactions.
True
Enzymes measure the amount of product formed per unit time to determine reaction rates.
True
Enzyme names ending in -ase always identify the reacting substance.
False
Enzyme names ending in -ase always describe the function of the enzyme.
True
Common names of digestion enzymes often end in -in.
True
Oxidoreductases catalyze redox reactions and have subclasses such as oxidases and dehydrogenases.
True
Transferases involve the transfer of functional groups between two substrates.
True
Hydrolases catalyze hydrolysis or addition of water.
True
Lyases remove atoms to form a double bond or add atoms to a double bond.
True
In enzyme nomenclature, the name 'pepsin' identifies an enzyme that digests starch.
False
In enzyme classification, lipases belong to the subclass of lyases.
False
Match the enzyme classification with its description:
Oxidoreductases = Catalyze redox reactions Transferases = Transfer of functional group between 2 substrates Hydrolases = Hydrolysis/addition of water Lyases = Add atoms to a double bond or remove atoms to form a double bond
Match the enzyme nomenclature with its example:
Amaylase = Digests starch Lactase = Digests lactose Oxidase = Catalyzes oxidation Hydrolase = Catalyzes hydrolysis
Match the enzyme common names with their function:
Pepsin = Digestion enzyme Trypsin = Digestion enzyme Oxidase = Catalyzes oxidation Hydrolase = Catalyzes hydrolysis
Match the subclass of lyases with its function:
Dehydrases = Add atoms to a double bond or remove atoms to form a double bond Decarboxylases = Add atoms to a double bond or remove atoms to form a double bond Deaminase = Add atoms to a double bond or remove atoms to form a double bond
Match the subclass of isomerases with their primary function:
Racemases = Alteration of the spatial arrangement of atoms in a molecule Mutases = Transfer of a functional group within a molecule Epimerases = Conversion of a molecule into its epimer
Match the enzyme property with its characteristic:
True catalyst and do not alter equilibrium constant = Enzymes are highly regulated and can readily adjust to the condition of the cell Highly specific = Enzymes are highly regulated and can readily adjust to the condition of the cell Highly regulated = Enzymes do not alter the equilibrium constant of a reaction
Match the enzyme structure component with its description:
Cofactors = Enzymes containing cofactors or coenzymes for their biological function Prosthetic groups = Tightly bound, specific nonpolypeptide units required for the biological function of enzymes Simple proteins only = Enzymes made up of simple proteins without any cofactors or prosthetic groups
Match the model of enzyme-substrate interaction with its description:
Lock-and-Key Model = Enzyme and substrate interact by means of short-range forces that require close contact Induced-Fit Model = Enzymes are flexible and the shapes of active sites can be modified by binding with a substrate
Match the way enzymes act on substrates with their description:
Entropy reduction = Restrains motion of molecules and holds them in place for reaction to proceed Acid/base catalysis = Involves proton transfer, which is common in biochemical reactions Covalent catalysis = Formation of a transient covalent bond between enzyme and substrate Metal ion catalysis = Involves bound metal cofactor that helps orient substrate for the reaction or stabilize charged transition states
Match the enzyme classification with its primary function:
Ligases = Combine molecules through aid of ATP Isomerases = Catalyze the rearrangement of atoms within a molecule Hydrolases = Catalyze hydrolysis or addition of water Oxidoreductases = Catalyze redox reactions
Test your knowledge about enzymes as biological catalysts and how reaction rates are measured. Learn about the role of enzymes in speeding up chemical reactions in living organisms.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
