Question 1

Organic cofactors are referred to as __________________.

Accepted Answer

coenzymes

Question 2

A __________________ inhibitor often has a structure similar to the substrate and often reversibly binds to the active site of the enzyme but can be displaced by substrate.

Accepted Answer

competitive

Question 3

What term is used to describe the dynamic recognition of the substrate when binding to an enzyme occurs?

Accepted Answer

A)  allosteric modulation 
B)  transition state enhancement 
C)  sequential binding 
D)  induced fit 
E)  None of the answers is correct. 
A)  allosteric modulation 
B)  transition state enhancement 
C)  sequential binding 
D)  induced fit 
E)  None of the answers is correct. D

Question 4

Which of the following is true?

Accepted Answer

A)  Enzymes force reactions to proceed in only one direction. 
B)  Enzymes alter the equilibrium of the reaction. 
C)  Enzymes alter the standard free energy of the reaction. 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  Enzymes force reactions to proceed in only one direction. 
B)  Enzymes alter the equilibrium of the reaction. 
C)  Enzymes alter the standard free energy of the reaction. 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 5

In many enzyme assays,the natural substrate and product are not used.Why?

Accepted Answer

Many products are difficult to measure a

Question 6

The kcat is often referred to as the _____.

Accepted Answer

A)  turnover number 
B)  Michaelis constant 
C)  dissociation constant 
D)  rate constant 
E)  None of the answers is correct. 
A)  turnover number 
B)  Michaelis constant 
C)  dissociation constant 
D)  rate constant 
E)  None of the answers is correct.

Question 7

Riboflavin is a water-soluble organic substance that is not synthesized by humans.Metabolically,it is chemically converted into a substance called flavin adenine dinucleotide,which is required by succinate dehydrogenase.Which of the following statements is most correct?

Accepted Answer

A)  Riboflavin is a coenzyme. 
B)  Flavin adenine dinucleotide is a vitamin. 
C)  Succinate dehydrogenase is a coenzyme. 
D)  Flavin adenine dinucleotide is a coenzyme. Succinate dehydrogenase is a vitamin. 
A)  Riboflavin is a coenzyme. 
B)  Flavin adenine dinucleotide is a vitamin. 
C)  Succinate dehydrogenase is a coenzyme. 
D)  Flavin adenine dinucleotide is a coenzyme. Succinate dehydrogenase is a vitamin.

Question 8

The KM is

Accepted Answer

A)  equal to the product concentration at initial reaction conditions. 
B)  equal to the substrate concentration when the reaction rate is half its maximal value. 
C)  proportional to the standard free energy. 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  equal to the product concentration at initial reaction conditions. 
B)  equal to the substrate concentration when the reaction rate is half its maximal value. 
C)  proportional to the standard free energy. 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 9

Explain what an abzyme is and give an example.

Accepted Answer

Catalytic antibodies are abzymes and are

Question 10

The straight-line kinetic plot of 1/ V0 versus 1/S is called a ________________________.

Accepted Answer

Lineweaver

Question 11

When ΔG for a system is zero,the system is at ______________________.

Accepted Answer

The answer of When ΔG for a system is zero,the...

Question 12

Compounds that resemble the transition state of a catalyzed reaction and inhibit enzyme activity are called ____________________________.

Accepted Answer

transition

Question 13

Most known enzymes are proteins; however,some ___________ molecules have been shown to possess catalytic activity.

Accepted Answer

The answer of Most known enzymes are proteins; however,some ___________...

Question 14

The difference between the standard-state free energy,ΔGº,and the biochemical standard-state free energy is that ΔGº′ refers to the standard free-energy change at ________.

Accepted Answer

The answer of The difference between the standard-state free energy,ΔGº,and...

Question 15

In this type of inhibition,the inhibitor can only bind to the ES complex to form an ESI complex.

Accepted Answer

A)  competitive 
B)  noncompetitive 
C)  mixed 
D)  uncompetitive 
E)  None of the answers is correct. 
A)  competitive 
B)  noncompetitive 
C)  mixed 
D)  uncompetitive 
E)  None of the answers is correct.

Question 16

The Gibbs-free energy of activation is the difference between the

Accepted Answer

A)  substrate and the transition state. 
B)  substrate and the product. 
C)  product and the transition state. 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  substrate and the transition state. 
B)  substrate and the product. 
C)  product and the transition state. 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 17

There are six basic categories of enzymes.List the categories,and define the type of reaction.

Accepted Answer

The categories include oxidoreductases (

Question 18

If a reaction is exergonic at specific reactant concentrations,it is considered _____.

Accepted Answer

A)  at equilibrium 
B)  nonspontaneous 
C)  spontaneous 
D)  irreversible 
E)  None of the answers is correct. 
A)  at equilibrium 
B)  nonspontaneous 
C)  spontaneous 
D)  irreversible 
E)  None of the answers is correct.

Question 19

The formula K'eq =   indicates the relationship between

Accepted Answer

A)  the free energy and the equilibrium constant. 
B)  the reaction equilibrium and the isomerization rate. 
C)  the equilibrium constant and standard free energy. 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  the free energy and the equilibrium constant. 
B)  the reaction equilibrium and the isomerization rate. 
C)  the equilibrium constant and standard free energy. 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 20

How do the intermediate steps in multisubstrate enzyme mechanisms differ?

Accepted Answer

In a sequential displacement reaction,bo

Exam 8: Enzymes: Basic Concepts and Kinetics

Organic cofactors are referred to as __________________.

A __________________ inhibitor often has a structure similar to the substrate and often reversibly binds to the active site of the enzyme but can be displaced by substrate.

What term is used to describe the dynamic recognition of the substrate when binding to an enzyme occurs?

Which of the following is true?

In many enzyme assays,the natural substrate and product are not used.Why?

The kcat is often referred to as the _____.

Riboflavin is a water-soluble organic substance that is not synthesized by humans.Metabolically,it is chemically converted into a substance called flavin adenine dinucleotide,which is required by succinate dehydrogenase.Which of the following statements is most correct?

The KM is

Explain what an abzyme is and give an example.

The straight-line kinetic plot of 1/ V0 versus 1/S is called a ________________________.

When ΔG for a system is zero,the system is at ______________________.

Compounds that resemble the transition state of a catalyzed reaction and inhibit enzyme activity are called ____________________________.

Most known enzymes are proteins; however,some ___________ molecules have been shown to possess catalytic activity.

The difference between the standard-state free energy,ΔGº,and the biochemical standard-state free energy is that ΔGº′ refers to the standard free-energy change at ________.

In this type of inhibition,the inhibitor can only bind to the ES complex to form an ESI complex.

The Gibbs-free energy of activation is the difference between the

There are six basic categories of enzymes.List the categories,and define the type of reaction.

If a reaction is exergonic at specific reactant concentrations,it is considered _____.

The formula K'eq = indicates the relationship between

How do the intermediate steps in multisubstrate enzyme mechanisms differ?

Biochemistry: An Evolving Science

Protein Composition and Structure

Exploring Proteins and Proteomes

DNA, RNA, and the Flow of Genetic Information

Exploring Genes and Genomes

Exploring Evolution and Bioinformatics

Hemoglobin: a Portrait of a Protein in Action

Catalytic Strategies

Regulatory Strategies

Carbohydrates

Lipids and Cell Membranes

Membrane Channels and Pumps

Signal-Transduction Pathways

Metabolism: Basic Concepts and Design

Glycolysis and Gluconeogenesis

The Citric Acid Cycle

Oxidative Phosphorylation

The Light Reactions of Photosynthesis

The Calvin Cycle and the Pentose Phosphate Pathway

Glycogen Metabolism

Fatty Acid Metabolism

Protein Turnover and Amino Acid Catabolism

The Biosynthesis of Amino Acids

Nucleotide Biosynthesis

Biosynthesis of Membrane Lipids and Steroids

The Integration of Metabolism

DNA Replication, repair, and Recombination

RNA Synthesis and Processing

Protein Synthesis

The Control of Gene Expression in Prokaryotes

The Control of Gene Expression in Eukaryotes

Sensory Systems

The Immune System

Molecular Motors

Drug Development

Filters

The k_cat is often referred to as the _____.

The K_M is

The straight-line kinetic plot of 1/ V₀ versus 1/S is called a ________________________.

The formula K'_eq = indicates the relationship between