Question 1

What type of secondary structure is in blue in the following protein?

Accepted Answer

A)  an α-helix 
B)  a parallel β-pleated sheet 
C)  an antiparallel β-pleated sheet 
D)  a random coil 
E)  This illustration does not show secondary structure. 
A)  an α-helix 
B)  a parallel β-pleated sheet 
C)  an antiparallel β-pleated sheet 
D)  a random coil 
E)  This illustration does not show secondary structure.

Question 2

The most common motifs for this level of structure are the helix and the F1F1F1S1F1F1F10- pleated sheet.

Accepted Answer

A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary 
A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary

Question 3

Sometimes, substitutions of one amino acid for another in a protein results in a large change in secondary and tertiary structure. Sometimes, the substitution leads to very little change. The structure of valine is shown below. Which of the choices of amino acids given would probably cause the least amount of perturbation to protein structure if it was substituted for a valine?

Accepted Answer

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

Question 4

Interleukin-4, a polypeptide, is shown below. In which of the following are the secondary structures labeled correctly?

Accepted Answer

A)  A: random folding B: β-pleated sheets C: α-helix 
B)  A: β-pleated sheets B: random folding C. α-helix 
C)  A: random folding B. α-helix C: β-pleated sheets 
D)  A. α-helix B: random folding C: β-pleated sheets 
E)  A: β-pleated sheets B: α-helix C: random folding 
A)  A: random folding B: β-pleated sheets C: α-helix 
B)  A: β-pleated sheets B: random folding C. α-helix 
C)  A: random folding B. α-helix C: β-pleated sheets 
D)  A. α-helix B: random folding C: β-pleated sheets 
E)  A: β-pleated sheets B: α-helix C: random folding

Question 5

During alkalosis 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

Question 6

Which of the following levels of architecture are not affected by denaturation?

Accepted Answer

A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  All levels of architecture are affected by denaturation. 
A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  All levels of architecture are affected by denaturation.

Question 7

The amino acid sequence is the ________ of a protein.

Accepted Answer

A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary 
A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary

Question 8

Which of the following structures is the enantiomer of l-alanine?

Accepted Answer

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

Question 9

What is indicated by the arrow pointing to part of the Fischer projection below?

Accepted Answer

A)  the beta carbon 
B)  the anomeric carbon 
C)  a center of chirality 
D)  a secondary amine 
E)  a peptide bond 
A)  the beta carbon 
B)  the anomeric carbon 
C)  a center of chirality 
D)  a secondary amine 
E)  a peptide bond

Question 10

Which of the following structures illustrates an amino acid as a zwitterion?

Accepted Answer

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

Question 11

Which of the following types of interactions result in proteins folding so that nonpolar residues are on the interior of the protein, protected from water?

Accepted Answer

A)  hydrogen bonds 
B)  salt bridges 
C)  disulfide bonds 
D)  hydrophilic interactions 
E)  dispersion forces 
A)  hydrogen bonds 
B)  salt bridges 
C)  disulfide bonds 
D)  hydrophilic interactions 
E)  dispersion forces

Question 12

Acetylcholine is a neurotransmitter that initiates muscle contraction. In order for muscle to relax after contraction, acetylcholine must be broken down into choline and acetate by the enzyme acetylcholinesterase. Nerve agents such as Sarin inhibit acetylcholinesterase by permanently covalently bonding to a serine amino acid in the active site of the enzyme, causing muscle paralysis. What type of inhibitor is Sarin?

Accepted Answer

A)  a competitive reversible inhibitor 
B)  a noncompetitive reversible inhibitor 
C)  a competitive irreversible inhibitor 
D)  a noncompetitive irreversible inhibitor 
E)  Sarin is not an inhibitor. 
A)  a competitive reversible inhibitor 
B)  a noncompetitive reversible inhibitor 
C)  a competitive irreversible inhibitor 
D)  a noncompetitive irreversible inhibitor 
E)  Sarin is not an inhibitor.

Question 13

The carbon with the asterisk next to it is called the

Accepted Answer

A)  anomeric carbon. 
B)  alpha carbon. 
C)  beta carbon. 
D)  gamma carbon. 
E)  side chain carbon. 
A)  anomeric carbon. 
B)  alpha carbon. 
C)  beta carbon. 
D)  gamma carbon. 
E)  side chain carbon.

Question 14

Enzymes are typically composed of this type of protein.

Accepted Answer

A)  keratin 
B)  keratin, elastin, and collagen 
C)  membrane proteins and globular proteins 
D)  globular proteins 
E)  membrane proteins 
A)  keratin 
B)  keratin, elastin, and collagen 
C)  membrane proteins and globular proteins 
D)  globular proteins 
E)  membrane proteins

Question 15

Which of the following choices is NOT a problem associated with sickle-cell anemia?

Accepted Answer

A)  People with sickle-cell anemia are prone to severe headaches. 
B)  People with sickle-cell anemia are prone to episodes of infection. 
C)  Organs can be damaged because of sickled red blood cells. 
D)  Sickle-cell anemia can cause anemia. 
E)  The sickle cells can aggregate and clog blood vessels. 
A)  People with sickle-cell anemia are prone to severe headaches. 
B)  People with sickle-cell anemia are prone to episodes of infection. 
C)  Organs can be damaged because of sickled red blood cells. 
D)  Sickle-cell anemia can cause anemia. 
E)  The sickle cells can aggregate and clog blood vessels.

Question 16

The pH for optimum activity for most enzymes is

Accepted Answer

A)  5.4. 
B)  7.4. 
C)  8.0. 
D)  9.0. 
E)  10.4. 
A)  5.4. 
B)  7.4. 
C)  8.0. 
D)  9.0. 
E)  10.4.

Question 17

Which of the following interactions holds the F1F1F1S1F1F1F10-helix and the F1F1F1S1F1F1F10-pleated sheet into its unique folding pattern?

Accepted Answer

A)  covalent bonding between cysteines (-CH2SH) 
B)  hydrogen bonding between serines (-CH2OH) 
C)  hydrogen bonding between nitrogens and oxygens in the amino acid backbone 
D)  ionic bonding between acidic and basic amino acid side chains 
E)  hydrophilic interactions 
A)  covalent bonding between cysteines (-CH2SH) 
B)  hydrogen bonding between serines (-CH2OH) 
C)  hydrogen bonding between nitrogens and oxygens in the amino acid backbone 
D)  ionic bonding between acidic and basic amino acid side chains 
E)  hydrophilic interactions

Question 18

This is a regular folding pattern in localized regions of the polypeptide backbone.

Accepted Answer

A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary 
A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  both secondary and tertiary

Question 19

Which type of protein signals cellular events?

Accepted Answer

A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins 
A)  receptors 
B)  structural proteins 
C)  immunoglobulins 
D)  transport proteins 
E)  dietary proteins

Question 20

-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 secondary structure?

Accepted Answer

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

What type of secondary structure is in blue in the following protein?

The most common motifs for this level of structure are the helix and the - pleated sheet.

Interleukin-4, a polypeptide, is shown below. In which of the following are the secondary structures labeled correctly?

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

Which of the following levels of architecture are not affected by denaturation?

The amino acid sequence is the ________ of a protein.

Which of the following structures is the enantiomer of l-alanine?

What is indicated by the arrow pointing to part of the Fischer projection below?

Which of the following structures illustrates an amino acid as a zwitterion?

Which of the following types of interactions result in proteins folding so that nonpolar residues are on the interior of the protein, protected from water?

The carbon with the asterisk next to it is called the

Enzymes are typically composed of this type of protein.

Which of the following choices is NOT a problem associated with sickle-cell anemia?

The pH for optimum activity for most enzymes is

Which of the following interactions holds the -helix and the -pleated sheet into its unique folding pattern?

This is a regular folding pattern in localized regions of the polypeptide backbone.

Which type of protein signals cellular events?

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Changes of State and the Gas Laws

Organic Chemistry: Hydrocarbons

Organic Chemistry and Biomolecules

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Acids and Bases

The Reactions of Organic Functional Groups in Biochemistry

Carbohydrates: Structure and Function

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Exam 13: Proteins: Structure and Function

What type of secondary structure is in blue in the following protein?

The most common motifs for this level of structure are the helix and the - pleated sheet.

Interleukin-4, a polypeptide, is shown below. In which of the following are the secondary structures labeled correctly?

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

Which of the following levels of architecture are not affected by denaturation?

The amino acid sequence is the ________ of a protein.

Which of the following structures is the enantiomer of l-alanine?

What is indicated by the arrow pointing to part of the Fischer projection below?

Which of the following structures illustrates an amino acid as a zwitterion?

Which of the following types of interactions result in proteins folding so that nonpolar residues are on the interior of the protein, protected from water?

The carbon with the asterisk next to it is called the

Enzymes are typically composed of this type of protein.

Which of the following choices is NOT a problem associated with sickle-cell anemia?

The pH for optimum activity for most enzymes is

Which of the following interactions holds the -helix and the -pleated sheet into its unique folding pattern?

This is a regular folding pattern in localized regions of the polypeptide backbone.

Which type of protein signals cellular events?

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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