Question 1

Which of the following is true?

Accepted Answer

A)  All enzymes are fibrous proteins. 
B)  All enzymes are globular proteins. 
C)  The majority of enzymes are fibrous proteins. 
D)  The majority of enzymes are globular proteins. 
A)  All enzymes are fibrous proteins. 
B)  All enzymes are globular proteins. 
C)  The majority of enzymes are fibrous proteins. 
D)  The majority of enzymes are globular proteins.

Question 2

Consider the following image depicting enzyme regulation.   Which of the following is depicted by this model?

Accepted Answer

A)  protein modification 
B)  allosterism 
C)  competitive inhibition 
D)  isoenzyme action 
A)  protein modification 
B)  allosterism 
C)  competitive inhibition 
D)  isoenzyme action

Question 3

What name is given to the organic cofactor of an enzyme?

Accepted Answer

A)  apoenzyme 
B)  chaperone 
C)  coenzyme 
D)  substrate 
A)  apoenzyme 
B)  chaperone 
C)  coenzyme 
D)  substrate

Question 4

Acetylcholinesterase belongs to which group of enzymes?

Accepted Answer

A)  hydrolases 
B)  lyases 
C)  oxidoreductases 
D)  transferases 
A)  hydrolases 
B)  lyases 
C)  oxidoreductases 
D)  transferases

Question 5

Consider the following graph for the rate of an enzyme catalyzed reaction.   Approximately, what would be the optimum temperature for carrying out this reaction?

Accepted Answer

A)  20°C 
B)  25°C 
C)  35°C 
D)  45°C 
E)  Any temperature between 20°C and 50°C. 
A)  20°C 
B)  25°C 
C)  35°C 
D)  45°C 
E)  Any temperature between 20°C and 50°C.

Question 6

Which of the following is true of enzymes?

Accepted Answer

A)  They shift the position of a chemical equilibrium. 
B)  They speed up the rate of a chemical reaction. 
C)  both a and b 
D)  neither a nor b 
A)  They shift the position of a chemical equilibrium. 
B)  They speed up the rate of a chemical reaction. 
C)  both a and b 
D)  neither a nor b

Question 7

Aconitase belongs to which group of enzymes?

Accepted Answer

A)  hydrolases 
B)  lyases 
C)  oxidoreductases 
D)  transferases 
A)  hydrolases 
B)  lyases 
C)  oxidoreductases 
D)  transferases

Question 8

Which of the following explains why succinylcholine is used as a muscle relaxant?

Accepted Answer

A)  It destroys acetylcholine esterase. 
B)  It is not hydrolyzed by acetylcholinesterase. 
C)  It is rapidly hydrolyzed by acetylcholinesterase. 
D)  It is slowly hydrolyzed by acetylcholinesterase. 
A)  It destroys acetylcholine esterase. 
B)  It is not hydrolyzed by acetylcholinesterase. 
C)  It is rapidly hydrolyzed by acetylcholinesterase. 
D)  It is slowly hydrolyzed by acetylcholinesterase.

Question 9

Which of the following is true of enzymes?

Accepted Answer

A)  They lower the activation energy for a chemical reaction. 
B)  They speed up the rate of a chemical reaction. 
C)  both a and b 
D)  neither a nor b 
A)  They lower the activation energy for a chemical reaction. 
B)  They speed up the rate of a chemical reaction. 
C)  both a and b 
D)  neither a nor b

Question 10

Which of the following is catalyzed by arginase?

Accepted Answer

A)  the conversion of D-arginine to urea and D-ornithine 
B)  the conversion of L-arginine to urea and L-ornithine 
C)  the conversion of L-arginine to urea and D-arginine 
D)  the conversion of both the D and L forms of arginine to urea and the D and L forms of ornithine 
A)  the conversion of D-arginine to urea and D-ornithine 
B)  the conversion of L-arginine to urea and L-ornithine 
C)  the conversion of L-arginine to urea and D-arginine 
D)  the conversion of both the D and L forms of arginine to urea and the D and L forms of ornithine

Question 11

What is the name given to a material which slows down enzyme function?

Accepted Answer

A)  closer 
B)  inhibitor 
C)  isozyme 
D)  substrate 
A)  closer 
B)  inhibitor 
C)  isozyme 
D)  substrate

Question 12

Competitive inhibition can be explained by which of the following models?

Accepted Answer

A)  the induced fit model 
B)  the lock and key model 
C)  both a and b 
D)  neither a nor b 
A)  the induced fit model 
B)  the lock and key model 
C)  both a and b 
D)  neither a nor b

Question 13

What name is given to any (organic or inorganic) nonprotein portion of an enzyme?

Accepted Answer

A)  apoenzyme 
B)  coenzyme 
C)  cofactor 
D)  substrate 
A)  apoenzyme 
B)  coenzyme 
C)  cofactor 
D)  substrate

Question 14

Examine the following graph.   Which of the following explains why the "line" on the graph does not continue in a linear fashion?

Accepted Answer

A)  All of the added substrate is bound to the enzyme. 
B)  All of the enzyme active sites are occupied. 
C)  The amount of enzyme present is greater than needed by the substrate. 
D)  An inhibitor is present. 
A)  All of the added substrate is bound to the enzyme. 
B)  All of the enzyme active sites are occupied. 
C)  The amount of enzyme present is greater than needed by the substrate. 
D)  An inhibitor is present.

Question 15

Which of the following is true?

Accepted Answer

A)  Both competitive and noncompetitive inhibition are never reversible. 
B)  Both competitive and noncompetitive inhibition are sometimes reversible. 
C)  Only competitive inhibition is sometimes reversible. 
D)  Only noncompetitive inhibition is sometimes reversible. 
A)  Both competitive and noncompetitive inhibition are never reversible. 
B)  Both competitive and noncompetitive inhibition are sometimes reversible. 
C)  Only competitive inhibition is sometimes reversible. 
D)  Only noncompetitive inhibition is sometimes reversible.

Question 16

What disease is diagnosed by monitoring acid phosphatase activity?

Accepted Answer

A)  hepatitis 
B)  liver cancer 
C)  pancreatic disease 
D)  prostate cancer 
A)  hepatitis 
B)  liver cancer 
C)  pancreatic disease 
D)  prostate cancer

Question 17

Noncompetitive inhibition can be often explained by which of the following models?

Accepted Answer

A)  the induced fit model 
B)  the lock and key model 
C)  both a and b 
D)  neither a nor b 
A)  the induced fit model 
B)  the lock and key model 
C)  both a and b 
D)  neither a nor b

Question 18

Consider the following graph for the rate of an enzyme catalyzed reaction.   What would be the optimum pH for carrying out this reaction?

Accepted Answer

A)  5.0 
B)  6.5 
C)  7.5 
D)  8.0 
E)  Any pH between 5.0 and 8.0. 
A)  5.0 
B)  6.5 
C)  7.5 
D)  8.0 
E)  Any pH between 5.0 and 8.0.

Question 19

In which type of inhibition does the inhibitor bind to the protein at a site other than the active site?

Accepted Answer

A)  cooperative inhibition 
B)  competitive inhibition 
C)  noncompetitive inhibition 
D)  selective inhibition 
A)  cooperative inhibition 
B)  competitive inhibition 
C)  noncompetitive inhibition 
D)  selective inhibition

Question 20

In which type of inhibition is it possible to restore the maximum rate of enzyme activity by adding additional substrate?

Accepted Answer

A)  cooperative inhibition 
B)  competitive inhibition 
C)  noncompetitive inhibition 
D)  selective inhibition 
A)  cooperative inhibition 
B)  competitive inhibition 
C)  noncompetitive inhibition 
D)  selective inhibition

Exam 23: Enzymes

Which of the following is true?

Consider the following image depicting enzyme regulation. Which of the following is depicted by this model?

What name is given to the organic cofactor of an enzyme?

Acetylcholinesterase belongs to which group of enzymes?

Consider the following graph for the rate of an enzyme catalyzed reaction. Approximately, what would be the optimum temperature for carrying out this reaction?

Which of the following is true of enzymes?

Aconitase belongs to which group of enzymes?

Which of the following explains why succinylcholine is used as a muscle relaxant?

Which of the following is true of enzymes?

Which of the following is catalyzed by arginase?

What is the name given to a material which slows down enzyme function?

Competitive inhibition can be explained by which of the following models?

What name is given to any (organic or inorganic) nonprotein portion of an enzyme?

Examine the following graph. Which of the following explains why the "line" on the graph does not continue in a linear fashion?

Which of the following is true?

What disease is diagnosed by monitoring acid phosphatase activity?

Noncompetitive inhibition can be often explained by which of the following models?

Consider the following graph for the rate of an enzyme catalyzed reaction. What would be the optimum pH for carrying out this reaction?

In which type of inhibition does the inhibitor bind to the protein at a site other than the active site?

In which type of inhibition is it possible to restore the maximum rate of enzyme activity by adding additional substrate?

Matter, Energy, and Measurement

Atoms

Chemical Bonds

Chemical Reactions

Gases, Liquids, and Solids

Solutions and Colloids

Reaction Rates and Chemical Equilibrium

Acids and Bases

Nuclear Chemistry

Organic Chemistry

Alkanes

Alkenes and Alkynes

Benzene and Its Derivatives

Alcohols, Ethers, and Thiols

Chirality: the Handedness of Molecules

Amines

Aldehydes and Ketones

Carboxylic Acids

Carboxylic Anhydrides, Esters, and Amides

Carbohydrates

Lipids

Proteins

Chemical Communications: Neurotransmitters and Hormones

Nucleotides, Nucleic Acids, and Heredity

Gene Expression and Protein Synthesis

Bioenergetics: How the Body Converts Food to Energy

Specific Catabolic Pathways: Carbohydrate, Lipid, and Protein Metabolism

Biosynthetic Pathways

Nutrition

Immunochemistry

Body Fluids

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