Question 1

Nonprotein catalysts are known as ________.

Accepted Answer

ribozymes

Question 2

The active site for many enzymes

Accepted Answer

A) contains amino acids that are contiguous to one another along the primary sequence of the protein. 
B) may require a prosthetic group such as a metal ion. 
C) involves amino acids that are brought into close proximity by extensive protein folding. 
D) usually depends on only one amino acid. 
E) involves amino acids that are brought into close proximity by extensive protein folding and may require a prosthetic group such as a metal ion. 
A) contains amino acids that are contiguous to one another along the primary sequence of the protein. 
B) may require a prosthetic group such as a metal ion. 
C) involves amino acids that are brought into close proximity by extensive protein folding. 
D) usually depends on only one amino acid. 
E) involves amino acids that are brought into close proximity by extensive protein folding and may require a prosthetic group such as a metal ion. E

Question 3

The type of inhibitor that binds to the enzyme active site 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 A

Question 4

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 5

Saturation can be defined as

Accepted Answer

A) denaturation of an enzyme. 
B) the inability to increase reaction velocity beyond a finite upper limit. 
C) inhibition of enzyme function by blocking the active site. 
D) the substrate concentration at which velocity reaches one-half maximum velocity. 
E) a characteristic of all uncatalyzed reactions. 
A) denaturation of an enzyme. 
B) the inability to increase reaction velocity beyond a finite upper limit. 
C) inhibition of enzyme function by blocking the active site. 
D) the substrate concentration at which velocity reaches one-half maximum velocity. 
E) a characteristic of all uncatalyzed reactions.

Question 6

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 7

Two specific coenzymes we need to obtain from our diet are niacin and ________,as our bodies cannot synthesize them.

Accepted Answer

The answer of Two specific coenzymes we need to obtain...

Question 8

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

Accepted Answer

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

Question 9

An enzyme reduces the free energy of which of the following?

Accepted Answer

A) substrate 
B) product 
C) transition state 
D) cofactor 
E) intermediate product 
A) substrate 
B) product 
C) transition state 
D) cofactor 
E) intermediate product

Question 10

Which of the following is an example of a prosthetic group?

Accepted Answer

A) a zinc ion 
B) a glycine residue 
C) a polypeptide chain 
D) a hydrogen ion 
E) carboxypeptidase A 
A) a zinc ion 
B) a glycine residue 
C) a polypeptide chain 
D) a hydrogen ion 
E) carboxypeptidase A

Question 11

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.

Question 12

Which of the following is not true of the enzyme-substrate interaction?

Accepted Answer

A) Many enzymes are extremely specific regarding a substrate. 
B) Many enzymes cannot recognize a stereoisomer of their substrate. 
C) Some enzymes accept any of a whole group of substrates. 
D) Carboxypeptidase recognizes any of the amino acids from the carboxyl end of a polypeptide. 
E) Cells are often able to carry out metabolic activity with only a handful of enzymes because many are nonspecific. 
A) Many enzymes are extremely specific regarding a substrate. 
B) Many enzymes cannot recognize a stereoisomer of their substrate. 
C) Some enzymes accept any of a whole group of substrates. 
D) Carboxypeptidase recognizes any of the amino acids from the carboxyl end of a polypeptide. 
E) Cells are often able to carry out metabolic activity with only a handful of enzymes because many are nonspecific.

Question 13

Of the following,which is used to inhibit specific enzymes in the treatment of many bacterial and viral diseases?

Accepted Answer

A) substrate analogues 
B) noncompetitive inhibitors 
C) denaturing agents 
D) allosteric regulation 
E) hydrogenases 
A) substrate analogues 
B) noncompetitive inhibitors 
C) denaturing agents 
D) allosteric regulation 
E) hydrogenases

Question 14

Mixed-type inhibitors will affect the ________ of an enzymatic reaction.

Accepted Answer

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

Question 15

Irreversible enzyme inhibitors

Accepted Answer

A) bind to the active site of an enzyme through noncovalent bonds. 
B) have only a temporary effect on enzyme activity. 
C) are often toxic to cells. 
D) are not active against ribozymes. 
E) are uncommon in nature. 
A) bind to the active site of an enzyme through noncovalent bonds. 
B) have only a temporary effect on enzyme activity. 
C) are often toxic to cells. 
D) are not active against ribozymes. 
E) are uncommon in nature.

Question 16

The rate of a reaction catalyzed by an enzymes usually ________ with temperature; however,at temperatures above the optimum range ________.

Accepted Answer

A) increases; protein denaturation occurs 
B) increases; the reaction proceeds without the enzyme 
C) decreases; the reaction proceeds without the enzyme 
D) increases; the direction of the reaction reverses 
E) decreases; prosthetic groups are necessary 
A) increases; protein denaturation occurs 
B) increases; the reaction proceeds without the enzyme 
C) decreases; the reaction proceeds without the enzyme 
D) increases; the direction of the reaction reverses 
E) decreases; prosthetic groups are necessary

Question 17

An example of an irreversible inhibitor is

Accepted Answer

A) a competitive inhibitor. 
B) angiotensin converting enzyme (AC
E) inhibiting drugs. 
C) a noncompetitive inhibitor. 
D) penicillin. 
E) isoleucine. 
A) a competitive inhibitor. 
B) angiotensin converting enzyme (AC
E) inhibiting drugs. 
C) a noncompetitive inhibitor. 
D) penicillin. 
E) isoleucine.

Question 18

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

Accepted Answer

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

Question 19

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

Accepted Answer

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

Question 20

Which of the following best describes a metastable state?

Accepted Answer

A) This state is composed of the difference in activation energy of a catalyzed versus an uncatalyzed reaction. 
B) The metastable state is formed by transient complexes with the substrate. 
C) The metastable state is created by the prosthetic group of the enzyme. 
D) This state changes the position of the equilibrium but not the rate. 
E) The metastable state is a state of the substrate in which the reaction can proceed but typically requires a catalyst. 
A) This state is composed of the difference in activation energy of a catalyzed versus an uncatalyzed reaction. 
B) The metastable state is formed by transient complexes with the substrate. 
C) The metastable state is created by the prosthetic group of the enzyme. 
D) This state changes the position of the equilibrium but not the rate. 
E) The metastable state is a state of the substrate in which the reaction can proceed but typically requires a catalyst.

Exam 6: Enzymes: the Catalysts of Life

Nonprotein catalysts are known as ________.

The active site for many enzymes

The type of inhibitor that binds to the enzyme active site is a(n)________ inhibitor.

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

Saturation can be defined as

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

Two specific coenzymes we need to obtain from our diet are niacin and ________,as our bodies cannot synthesize them.

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

An enzyme reduces the free energy of which of the following?

Which of the following is an example of a prosthetic group?

An allosteric inhibitor

Which of the following is not true of the enzyme-substrate interaction?

Of the following,which is used to inhibit specific enzymes in the treatment of many bacterial and viral diseases?

Mixed-type inhibitors will affect the ________ of an enzymatic reaction.

Irreversible enzyme inhibitors

The rate of a reaction catalyzed by an enzymes usually ________ with temperature; however,at temperatures above the optimum range ________.

An example of an irreversible inhibitor is

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

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

Which of the following best describes a metastable state?

A Preview of Cell Biology

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

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

DNA Replication, repair, and Recombination

Gene Expression: Ithe Genetic Code and Transcription

Gene Expression: Iiprotein Synthesis and Sorting

The Regulation of Gene Expression

Molecular Biology Techniques for Cell Biology

Signal Transduction Mechanisms: Ielectrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Iimessengers and Receptors

The Cell Cycle and Mitosis

Sexual Reproduction,meiosis,and Genetic Recombination

Filters

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

The rate of a reaction catalyzed by an enzymes usually with temperature; however,at temperatures above the optimum range .