Question 1

The equation v = Vmax [S]/(Km + [S])is part of which of the following plots?

Accepted Answer

A) Michaelis-Menten 
B) Lineweaver-Burk 
C) Eadie-Hofstee 
D) both choices A and B 
E) none of the above 
A) Michaelis-Menten 
B) Lineweaver-Burk 
C) Eadie-Hofstee 
D) both choices A and B 
E) none of the above

Question 2

The equation AB + H₂O → A + B would be catalyzed by which of the following classes of enzymes?

Accepted Answer

A) oxidoreductases 
B) transferases 
C) hydrolases 
D) ligases 
E) isomerases 
A) oxidoreductases 
B) transferases 
C) hydrolases 
D) ligases 
E) isomerases

Question 3

________ inhibitors bind reversibly at the active site of an enzyme.

Accepted Answer

The answer of ________ inhibitors bind reversibly at the active...

Question 4

________ are a class of enzymes responsible for the movement of functional groups from one molecule to another.

Accepted Answer

The answer of ________ are a class of enzymes responsible...

Question 5

The site on an enzyme that will bind the substrate is called the

Accepted Answer

A) prosthetic group. 
B) catalyst. 
C) active site. 
D) metastable site. 
E) activation site. 
A) prosthetic group. 
B) catalyst. 
C) active site. 
D) metastable site. 
E) activation site.

Question 6

Substrate activation may involve

Accepted Answer

A) a change in enzyme conformation induced by substrate binding. 
B) accepting protons from the enzyme. 
C) formation of temporary covalent bonds. 
D) donation of protons to the enzyme. 
E) all of the above 
A) a change in enzyme conformation induced by substrate binding. 
B) accepting protons from the enzyme. 
C) formation of temporary covalent bonds. 
D) donation of protons to the enzyme. 
E) all of the above

Question 7

Why is the Lineweaver-Burk plot important in enzyme kinetics?

Accepted Answer

A) It is a single-reciprocal plot. 
B) It illustrates enzyme specificity. 
C) It reveals the presence of prosthetic groups in enzymes. 
D) It makes it easier to determine Vmax. 
E) It is nonlinear. 
A) It is a single-reciprocal plot. 
B) It illustrates enzyme specificity. 
C) It reveals the presence of prosthetic groups in enzymes. 
D) It makes it easier to determine Vmax. 
E) It is nonlinear.

Question 8

All of the following are examples of ribozymes or ribozyme activity except

Accepted Answer

A) peptidyl transferase. 
B) autocatalytic RNAs. 
C) ribonuclease P. 
D) intron removal from pre-rRNA. 
E) zymogen. 
A) peptidyl transferase. 
B) autocatalytic RNAs. 
C) ribonuclease P. 
D) intron removal from pre-rRNA. 
E) zymogen.

Question 9

The induced-fit model

Accepted Answer

A) was proposed by Hans Buchner. 
B) involves a conformational change in the shape of the enzyme. 
C) is also called the lock-and-key model. 
D) states that enzyme-substrate interactions are rigid. 
E) proposes that very strong covalent bonds are formed upon substrate binding. 
A) was proposed by Hans Buchner. 
B) involves a conformational change in the shape of the enzyme. 
C) is also called the lock-and-key model. 
D) states that enzyme-substrate interactions are rigid. 
E) proposes that very strong covalent bonds are formed upon substrate binding.

Question 10

Enzyme regulation may occur by several methods.Which of the following is not a means of enzyme regulation?

Accepted Answer

A) substrate-level phosphorylation 
B) feedback inhibition 
C) allosteric regulation 
D) covalent modification 
E) saturation 
A) substrate-level phosphorylation 
B) feedback inhibition 
C) allosteric regulation 
D) covalent modification 
E) saturation

Question 11

A noncompetitive inhibitor will affect the ________ of an enzymatic reaction.

Accepted Answer

A) Km 
B) Vmax 
C) S 
D) P 
E) both choices A and B 
A) Km 
B) Vmax 
C) S 
D) P 
E) both choices A and B

Question 12

A competitive inhibitor will affect the ________ of an enzymatic reaction.

Accepted Answer

A) Km 
B) Vmax 
C) S 
D) P 
E) both choices A and B 
A) Km 
B) Vmax 
C) S 
D) P 
E) both choices A and B

Question 13

________ is the class of enzymes able to convert a substrate to its mirror image.

Accepted Answer

The answer of ________ is the class of enzymes able...

Question 14

The work of James B.Sumner was to

Accepted Answer

A) discover ribozymes. 
B) prove that enzymes were carbohydrates. 
C) isolate the insulin hormone. 
D) originate the term ferments to describe enzymes. 
E) crystallize urease, the first enzyme isolated. 
A) discover ribozymes. 
B) prove that enzymes were carbohydrates. 
C) isolate the insulin hormone. 
D) originate the term ferments to describe enzymes. 
E) crystallize urease, the first enzyme isolated.

Question 15

________ is the turnover number for a given enzyme.

Accepted Answer

The answer of ________ is the turnover number for a...

Question 16

The type of inhibitor that binds to the enzyme (E)but not to the enzyme-substrate (ES)complex is a(n)________ inhibitor.

Accepted Answer

A) competitive 
B) noncompetitive 
C) uncompetitive 
D) coenzyme 
E) mixed-type 
A) competitive 
B) noncompetitive 
C) uncompetitive 
D) coenzyme 
E) mixed-type

Question 17

A nonprotein component of an enzyme that is usually a metal ion or small organic molecule is called a(n)________.

Accepted Answer

The answer of A nonprotein component of an enzyme that...

Question 18

A linear relationship between Vmax and enzyme concentration would be expected when

Accepted Answer

A) [S] > Km. 
C) [S] = Km. 
D) both choices A and B 
E) both choices B and C 
A) [S] > Km. 
C) [S] = Km. 
D) both choices A and B 
E) both choices B and C

Question 19

The ________ velocity of an enzymatic reaction is the velocity at substrate concentration.

Accepted Answer

The answer of The ________ velocity of an enzymatic reaction...

Question 20

An allosteric inhibitor

Accepted Answer

A) increases the rate of substrate binding. 
B) binds and activates the high-affinity state of the enzymes. 
C) is identical to the active site. 
D) binds at the regulatory site. 
E) is converted to an activator by the enzyme. 
A) increases the rate of substrate binding. 
B) binds and activates the high-affinity state of the enzymes. 
C) is identical to the active site. 
D) binds at the regulatory site. 
E) is converted to an activator by the enzyme.

Exam 6: Enzymes: the Catalysts of Life

The equation v = Vmax [S]/(Km + [S])is part of which of the following plots?

The equation AB + H₂O → A + B would be catalyzed by which of the following classes of enzymes?

________ inhibitors bind reversibly at the active site of an enzyme.

________ are a class of enzymes responsible for the movement of functional groups from one molecule to another.

The site on an enzyme that will bind the substrate is called the

Substrate activation may involve

Why is the Lineweaver-Burk plot important in enzyme kinetics?

All of the following are examples of ribozymes or ribozyme activity except

The induced-fit model

Enzyme regulation may occur by several methods.Which of the following is not a means of enzyme regulation?

A noncompetitive inhibitor will affect the ________ of an enzymatic reaction.

A competitive inhibitor will affect the ________ of an enzymatic reaction.

________ is the class of enzymes able to convert a substrate to its mirror image.

The work of James B.Sumner was to

________ is the turnover number for a given enzyme.

The type of inhibitor that binds to the enzyme (E)but not to the enzyme-substrate (ES)complex is a(n)________ inhibitor.

A nonprotein component of an enzyme that is usually a metal ion or small organic molecule is called a(n)________.

A linear relationship between Vmax and enzyme concentration would be expected when

The ________ velocity of an enzymatic reaction is the velocity at substrate concentration.

An allosteric inhibitor

A Preview of the Cell

The Chemistry of the Cell

The Macromolecules of the Cell

Cells and Organelles

Bioenergetics: the Flow of Energy in the Cell

Membranes: Their Structure, function, and Chemistry

Transport Across Membranes: Overcoming the Permeability Barrier

Chemotrophic Energy Metabolism: Glycolysis and Fermentation

Chemotrophic Energy Metabolism: Aerobic Respiration

Phototrophic Energy Metabolism: Photosynthesis

The Endomembrane System and Peroxisomes

Signal Transduction Mechanisms: Ielectrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Iimessengers and Receptors

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesions, cell Junctions, and Extracellular Structures

The Structural Basis of Cellular Information: DNA, chromosomes, and the Nucleus

The Cell Cycle, DNA Replication, and Mitosis

Sexual Reproduction, meiosis, and Genetic Recombination

Gene Expression: Ithe Genetic Code and Transcription

Gene Expression: Iiprotein Synthesis and Sorting

The Regulation of Gene Expression

Cancer Cells

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