Question 1

The boxed bond in the following peptide is a

Accepted Answer

A)  peptide bond. 
B)  ionic bond. 
C)  nonpolar covalent bond. 
D)  hydrogen bond. 
E)  chiral carbon. 
A)  peptide bond. 
B)  ionic bond. 
C)  nonpolar covalent bond. 
D)  hydrogen bond. 
E)  chiral carbon. A

Question 2

During acidosis of a protein, shown below, salt bridges are broken, resulting in denaturation. Which choice shows the products of alkalosis?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  e 
A)  a 
B)  b 
C)  c 
D)  d 
E)  e D

Question 3

A protein acts as a catalyst if its name ends with

Accepted Answer

A)  -ase. 
B)  -ate. 
C)  -ine. 
D)  -ous. 
E)  -ite. 
A)  -ase. 
B)  -ate. 
C)  -ine. 
D)  -ous. 
E)  -ite. A

Question 4

What is the molecular shape of the carbon with the asterisk next to it?

Accepted Answer

A)  linear 
B)  bent 
C)  trigonal planar 
D)  tetrahedral 
E)  pyramidal 
A)  linear 
B)  bent 
C)  trigonal planar 
D)  tetrahedral 
E)  pyramidal

Question 5

An amino acid zwitterion has

Accepted Answer

A)  a net positive charge. 
B)  a net negative charge. 
C)  a net neutral charge. 
D)  any non-neutral charge. 
E)  Zwitterions can have any charge. 
A)  a net positive charge. 
B)  a net negative charge. 
C)  a net neutral charge. 
D)  any non-neutral charge. 
E)  Zwitterions can have any charge.

Question 6

Below is a graph of enzyme activity as a function of pH. Given the information on this graph, where is pepsin most likely to be found?

Accepted Answer

A)  stomach (pH 2) 
B)  liver (pH 5) 
C)  pancreas (pH 7) 
D)  blood (pH 7.4) 
E)  small intestine (pH 8) 
A)  stomach (pH 2) 
B)  liver (pH 5) 
C)  pancreas (pH 7) 
D)  blood (pH 7.4) 
E)  small intestine (pH 8)

Question 7

In an enzyme catalyzed reaction, the reactant that the enzyme acts upon is called the

Accepted Answer

A)  prosthetic group, 
B)  substrate, 
C)  coenzyme, 
D)  reagent, 
E)  cofactor, 
A)  prosthetic group, 
B)  substrate, 
C)  coenzyme, 
D)  reagent, 
E)  cofactor,

Question 8

Which of the following amino acid side chains is most often involved in hydrogen bonding?

Accepted Answer

A)  -CH3 
B)  -CH2OH 
C)  -COOH 
D)  -CH2CH2SCH3 
E)  All of the above 
A)  -CH3 
B)  -CH2OH 
C)  -COOH 
D)  -CH2CH2SCH3 
E)  All of the above

Question 9

The following is a description of an enzyme called superoxide dismutase. Refer to this paragraph to answer the following question. Superoxide dismutase is an enzyme that detoxifies a free radical called superoxide. This radical is responsible for causing injury during reperfusion after a heart attack, and is also thought to play a role in Parkinson's Disease.a Depending on what organism the protein is found in, it occurs either as a dimer or tetramer of identical subunits.b The subunits are mostly F1F1F1S1F1F1F10-helical with some β-sheet near the C-terminus.c A metal binding site for manganese, iron, nickel or copper/zinc is composed of residues from both the N-terminus and the C-terminus.d These residues are: His-26, His-81, Asp-167, His-171.e
Which statement refers to a prosthetic group?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  e 
A)  a 
B)  b 
C)  c 
D)  d 
E)  e

Question 10

Which of the following statements about noncompetitive inhibitors is FALSE?

Accepted Answer

A)  Noncompetitive inhibitors are sometimes involved in feedback inhibition. 
B)  Noncompetitive inhibitors can serve a regulatory role in the body. 
C)  Noncompetitive inhibitors do not bind to the active site of an enzyme. 
D)  Increasing the concentration of a substrate restores function of an enzyme in the presence of a noncompetitive inhibitor. 
E)  Binding of a noncompetitive inhibitor results in deformation of an enzyme's active site. 
A)  Noncompetitive inhibitors are sometimes involved in feedback inhibition. 
B)  Noncompetitive inhibitors can serve a regulatory role in the body. 
C)  Noncompetitive inhibitors do not bind to the active site of an enzyme. 
D)  Increasing the concentration of a substrate restores function of an enzyme in the presence of a noncompetitive inhibitor. 
E)  Binding of a noncompetitive inhibitor results in deformation of an enzyme's active site.

Question 11

Is this amino acid L- or D-, and how can you tell?

Accepted Answer

A)  L-, because all amino acids are L. 
B)  D-, because all amino acids are D. 
C)  D-, because the amine is on the right. 
D)  D-, because the amine is on the left. 
E)  L-, because the amine is on the left. 
A)  L-, because all amino acids are L. 
B)  D-, because all amino acids are D. 
C)  D-, because the amine is on the right. 
D)  D-, because the amine is on the left. 
E)  L-, because the amine is on the left.

Question 12

Select the statement that best described a key difference between competitive and noncompetitive inhibitors.

Accepted Answer

A)  A competitive inhibitor binds to the active site and a noncompetitive inhibitor does not. 
B)  A noncompetitive inhibitor binds to the active site and a competitive inhibitor does not. 
C)  A competitive inhibitor is more effective than a noncompetitive inhibitor. 
D)  A noncompetitive inhibitor is more effective than a competitive inhibitor. 
E)  A noncompetitive inhibitor has structural similarities to the enzyme's active site and the competitive inhibitor does not. 
A)  A competitive inhibitor binds to the active site and a noncompetitive inhibitor does not. 
B)  A noncompetitive inhibitor binds to the active site and a competitive inhibitor does not. 
C)  A competitive inhibitor is more effective than a noncompetitive inhibitor. 
D)  A noncompetitive inhibitor is more effective than a competitive inhibitor. 
E)  A noncompetitive inhibitor has structural similarities to the enzyme's active site and the competitive inhibitor does not.

Question 13

The purpose of an enzyme is to

Accepted Answer

A)  be structural in nature. 
B)  transport key molecules. 
C)  defend the body against infectious agents. 
D)  catalyze chemical reactions. 
E)  All of these are purposes of enzymes. 
A)  be structural in nature. 
B)  transport key molecules. 
C)  defend the body against infectious agents. 
D)  catalyze chemical reactions. 
E)  All of these are purposes of enzymes.

Question 14

Which of the following are methods of denaturing a protein?

Accepted Answer

A)  pH changes 
B)  heating 
C)  mechanical agitation 
D)  detergents 
E)  All of the above 
A)  pH changes 
B)  heating 
C)  mechanical agitation 
D)  detergents 
E)  All of the above

Question 15

Which of the following structures illustrates how an amino acid reacts in a low pH solution?

Accepted Answer

A)   
B)   
C)   
D)   
E) All of these reactions occur to the same extent in a solution with a pH less than 7 . 
A)   
B)   
C)   
D)   
E) All of these reactions occur to the same extent in a solution with a pH less than 7 .

Question 16

An enzyme inhibitor is a compound that

Accepted Answer

A)  prevents a substrate from binding to the enzyme. 
B)  deforms enzymes. 
C)  binds to the active site of an enzyme. 
D)  prevents an enzyme from functioning. 
E)  can do all of the above. 
A)  prevents a substrate from binding to the enzyme. 
B)  deforms enzymes. 
C)  binds to the active site of an enzyme. 
D)  prevents an enzyme from functioning. 
E)  can do all of the above.

Question 17

In which of the following structures is the box ONLY around the amino acid side chain?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 18

-The following is a description of an enzyme called superoxide dismutase. Refer to this paragraph to answer the following question. Superoxide dismutase is an enzyme that detoxifies a free radical called superoxide. This radical is responsible for causing injury during reperfusion after a heart attack, and is also thought to play a role in Parkinson's Disease.a Depending on what organism the protein is found in, it occurs either as a dimer or tetramer of identical subunits.b The subunits are mostly F1F1F1S1F1F1F10-helical with some β-sheet near the C-terminus.c A metal binding site for manganese, iron, nickel or copper/zinc is composed of residues from both the N-terminus and the C-terminus.d These residues are: His-26, His-81, Asp-167, His-171.e
Which statement refers to quaternary structure?

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
E)  e 
A)  a 
B)  b 
C)  c 
D)  d 
E)  e

Question 19

Sickle-cell anemia is caused by

Accepted Answer

A)  an abnormal form of acetylcholine. 
B)  an abnormal form of iron. 
C)  too little iron. 
D)  an abnormal form of hemoglobin. 
E)  Actually, the cause of this disease is unknown. 
A)  an abnormal form of acetylcholine. 
B)  an abnormal form of iron. 
C)  too little iron. 
D)  an abnormal form of hemoglobin. 
E)  Actually, the cause of this disease is unknown.

Question 20

What types of biomolecules are enzymes?

Accepted Answer

A)  only proteins 
B)  only DNA molecules 
C)  proteins and some carbohydrates 
D)  proteins and some RNA molecules 
E)  carbohydrates and some RNA molecules 
A)  only proteins 
B)  only DNA molecules 
C)  proteins and some carbohydrates 
D)  proteins and some RNA molecules 
E)  carbohydrates and some RNA molecules

The boxed bond in the following peptide is a

During acidosis of a protein, shown below, salt bridges are broken, resulting in denaturation. Which choice shows the products of alkalosis?

A protein acts as a catalyst if its name ends with

What is the molecular shape of the carbon with the asterisk next to it?

An amino acid zwitterion has

Below is a graph of enzyme activity as a function of pH. Given the information on this graph, where is pepsin most likely to be found?

In an enzyme catalyzed reaction, the reactant that the enzyme acts upon is called the

Which of the following amino acid side chains is most often involved in hydrogen bonding?

Which of the following statements about noncompetitive inhibitors is FALSE?

Is this amino acid L- or D-, and how can you tell?

Select the statement that best described a key difference between competitive and noncompetitive inhibitors.

The purpose of an enzyme is to

Which of the following are methods of denaturing a protein?

Which of the following structures illustrates how an amino acid reacts in a low pH solution?

An enzyme inhibitor is a compound that

In which of the following structures is the box ONLY around the amino acid side chain?

Sickle-cell anemia is caused by

What types of biomolecules are enzymes?

Measuring Matter and Energy

Atomic Structure and Nuclear Radiation

Compounds and Molecules

Chemical Quantities and Chemical Reactions

Changes of State and the Gas Laws

Organic Chemistry: Hydrocarbons

Organic Chemistry and Biomolecules

Solutions, Colloids and Membranes

Acids and Bases

The Reactions of Organic Functional Groups in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

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Exam 13: Proteins: Structure and Function

The boxed bond in the following peptide is a

During acidosis of a protein, shown below, salt bridges are broken, resulting in denaturation. Which choice shows the products of alkalosis?

A protein acts as a catalyst if its name ends with

What is the molecular shape of the carbon with the asterisk next to it?

An amino acid zwitterion has

Below is a graph of enzyme activity as a function of pH. Given the information on this graph, where is pepsin most likely to be found?

In an enzyme catalyzed reaction, the reactant that the enzyme acts upon is called the

Which of the following amino acid side chains is most often involved in hydrogen bonding?

Which of the following statements about noncompetitive inhibitors is FALSE?

Is this amino acid L- or D-, and how can you tell?

Select the statement that best described a key difference between competitive and noncompetitive inhibitors.

The purpose of an enzyme is to

Which of the following are methods of denaturing a protein?

Which of the following structures illustrates how an amino acid reacts in a low pH solution?

An enzyme inhibitor is a compound that

In which of the following structures is the box ONLY around the amino acid side chain?

Sickle-cell anemia is caused by

What types of biomolecules are enzymes?

Measuring Matter and Energy

Atomic Structure and Nuclear Radiation

Compounds and Molecules

Chemical Quantities and Chemical Reactions

Changes of State and the Gas Laws

Organic Chemistry: Hydrocarbons

Organic Chemistry and Biomolecules

Solutions, Colloids and Membranes

Acids and Bases

The Reactions of Organic Functional Groups in Biochemistry

Carbohydrates: Structure and Function

Lipids: Structure and Function

Nucleotides and Nucleic Acids

Energy and Metabolism

Filters