Question 1

What kinds of polypeptide domains are found in native proteins?

Accepted Answer

A)  alpha-helix 
B)  Pleated sheet 
C)  Irregularly folded 
D)  All of the above 
E)  none of the above 
A)  alpha-helix 
B)  Pleated sheet 
C)  Irregularly folded 
D)  All of the above 
E)  none of the above

Question 2

Which of the following describes the side chain of glutamine?

Accepted Answer

A)  contains a branched chain hydrocarbon 
B)  contains a sulfhydryl group 
C)  contains an aromatic ring 
D)  contains a methyl group 
E)  contains an amide 
A)  contains a branched chain hydrocarbon 
B)  contains a sulfhydryl group 
C)  contains an aromatic ring 
D)  contains a methyl group 
E)  contains an amide

Question 3

Glutamic acid (pK1 = 2.0, pK2 = 4.0, pK3 = 10.0) is dissolved in water. The isoelectric point (pI) of glutamic acid is

Accepted Answer

A)  2.0 
B)  3.0 
C)  4.0 
D)  7.0 
E)  10.0 
A)  2.0 
B)  3.0 
C)  4.0 
D)  7.0 
E)  10.0

Question 4

All of the following statements regarding collagen are correct EXCEPT which one?

Accepted Answer

A)  Collagen is the most abundant protein in the human. 
B)  Collagen has an amino acid composition typical of that found in most soluble proteins. 
C)  Collagen is a very inelastic protein in the native state. 
D)  Collagen is a very insoluble protein in the native state. 
E)  Collagen is made up of subunits termed tropocollagen. 
A)  Collagen is the most abundant protein in the human. 
B)  Collagen has an amino acid composition typical of that found in most soluble proteins. 
C)  Collagen is a very inelastic protein in the native state. 
D)  Collagen is a very insoluble protein in the native state. 
E)  Collagen is made up of subunits termed tropocollagen.

Question 5

Which of the following mutations would you expect to cause the most drastic alteration in the functional performance of a polypeptide chain? (Assuming the replacement is not at the active site)

Accepted Answer

A)  Replacement of glutamate with lysine. 
B)  Replacement of valine with alanine. 
C)  Replacement of aspartic acid with glutamic acid. 
D)  Replacement of lysine with arginine. 
A)  Replacement of glutamate with lysine. 
B)  Replacement of valine with alanine. 
C)  Replacement of aspartic acid with glutamic acid. 
D)  Replacement of lysine with arginine.

Question 6

Which of the following is not a feature of collagen?

Accepted Answer

A)  a repeating tripeptide sequence, Gly-Xaa-Pro or Gly-Xaa-HyPro 
B)  a long triple helix 
C)  the unusual amino acid hydroxyproline 
D)  glycine at every third residue of the helix 
E)  beta-pleated sheet secondary structure 
A)  a repeating tripeptide sequence, Gly-Xaa-Pro or Gly-Xaa-HyPro 
B)  a long triple helix 
C)  the unusual amino acid hydroxyproline 
D)  glycine at every third residue of the helix 
E)  beta-pleated sheet secondary structure

Question 7

The primary structure of a protein refers to its

Accepted Answer

A)  ability to form intrachain hydrogen bonds. 
B)  amino acid sequence. 
C)  folding induced by disulfide linkages. 
D)  ability to form subunit structures. 
E)  ability to form interchain hydrogen bonds. 
A)  ability to form intrachain hydrogen bonds. 
B)  amino acid sequence. 
C)  folding induced by disulfide linkages. 
D)  ability to form subunit structures. 
E)  ability to form interchain hydrogen bonds.

Question 8

The largest part of the driving force causing protein chains to fold into compact, globular structures is typically

Accepted Answer

A)  electrostatic force. 
B)  hydrogen bonding. 
C)  hydrophobic bonding. 
D)  polar group interaction. 
E)  alpha helix formation. 
A)  electrostatic force. 
B)  hydrogen bonding. 
C)  hydrophobic bonding. 
D)  polar group interaction. 
E)  alpha helix formation.

Question 9

In the peptide below, what would be an initial product of the Edman reaction? ala-val-met-glu-ile-trp-ser-cys-glu

Accepted Answer

A)  ala-val-met 
B)  Fluorescamine derivative of alanine 
C)  fluorescamine derivative of alanine 
D)  Phenylhydantoin derivative of alanine 
E)  valine 
A)  ala-val-met 
B)  Fluorescamine derivative of alanine 
C)  fluorescamine derivative of alanine 
D)  Phenylhydantoin derivative of alanine 
E)  valine

Question 10

What are the characteristics of proteins that are used for separation by 2-D gel electrophoresis in the first and second dimension respectively?

Accepted Answer

A)  Affinity/charge 
B)  Mass/affinity 
C)  Mass/charge 
D)  PI/mass 
E)  Shape/charge 
A)  Affinity/charge 
B)  Mass/affinity 
C)  Mass/charge 
D)  PI/mass 
E)  Shape/charge

Question 11

The surface shell of a lipoprotein such as a chylomicron or very low density lipoprotein (VLDL) is composed chiefly of

Accepted Answer

A)  phospholipid. 
B)  cholesterol ester. 
C)  triglyceride. 
D)  ganglioside. 
A)  phospholipid. 
B)  cholesterol ester. 
C)  triglyceride. 
D)  ganglioside.

Question 12

Which of the following groups of amino acid residues would be expected to have all of their side chains in a charged state at physiological pH?

Accepted Answer

A)  Glu, Tyr, Asn 
B)  Met, Cys, Lys 
C)  His, Ser, Arg 
D)  Asp, His, Tyr 
E)  Arg, Asp, Lys 
A)  Glu, Tyr, Asn 
B)  Met, Cys, Lys 
C)  His, Ser, Arg 
D)  Asp, His, Tyr 
E)  Arg, Asp, Lys

Question 13

A protein whose isoelectric point is 5.3 will exhibit minimum solubility at pH

Accepted Answer

A)  3.3 
B)  4.3 
C)  5.3 
D)  6.3 
E)  7.3 
A)  3.3 
B)  4.3 
C)  5.3 
D)  6.3 
E)  7.3

Question 14

A class of proteins which is distinguished by very low solubility in pure water is the

Accepted Answer

A)  globulins 
B)  lipoproteins 
C)  albumins 
D)  glycoproteins 
E)  globular proteins 
A)  globulins 
B)  lipoproteins 
C)  albumins 
D)  glycoproteins 
E)  globular proteins

Question 15

Protein-protein hydrogen bonding is involved in all of the following structural features in proteins EXCEPT

Accepted Answer

A)  alpha-helix. 
B)  Beta-sheet conformation. 
C)  Reverse-turn (beta bend). 
D)  Random coil. 
E)  Collagen triple helix. 
A)  alpha-helix. 
B)  Beta-sheet conformation. 
C)  Reverse-turn (beta bend). 
D)  Random coil. 
E)  Collagen triple helix.

Question 16

If two proteins have the same molecular weight then it follows that they also have

Accepted Answer

A)  the same amino acid composition. 
B)  the same sedimentation coefficient. 
C)  the same diffusion coefficient. 
D)  the same conformation. 
E)  none of the above 
A)  the same amino acid composition. 
B)  the same sedimentation coefficient. 
C)  the same diffusion coefficient. 
D)  the same conformation. 
E)  none of the above

Question 17

amino acid side chains which may be involved in hydrogen bonding in proteins include

Accepted Answer

A)  leucine. 
B)  isoleucine. 
C)  alanine. 
D)  tyrosine. 
E)  phenylalanine. 
A)  leucine. 
B)  isoleucine. 
C)  alanine. 
D)  tyrosine. 
E)  phenylalanine.

Question 18

Which of the following statements about protein structure is correct?

Accepted Answer

A)  Disulfide interactions are required for the stability of globular structures. 
B)  Hydrophobic sidechains commonly occur clustered in interior areas of globular proteins. 
C)  The alpha-helix is maintained chiefly by hydrophobic interactions. 
D)  Covalent linkages between the protomeric chains are a common feature of globular oligomeric proteins such as hemoglobin and lactate dehydrogenase (LDH). 
E)  Pleated-sheet structures are found only in fibrous proteins. 
A)  Disulfide interactions are required for the stability of globular structures. 
B)  Hydrophobic sidechains commonly occur clustered in interior areas of globular proteins. 
C)  The alpha-helix is maintained chiefly by hydrophobic interactions. 
D)  Covalent linkages between the protomeric chains are a common feature of globular oligomeric proteins such as hemoglobin and lactate dehydrogenase (LDH). 
E)  Pleated-sheet structures are found only in fibrous proteins.

Question 19

Which one of the following bonds is LEAST likely to break during protein denaturation?

Accepted Answer

A)  Hydrophobic 
B)  Hydrogen 
C)  Disulfide 
D)  Lipophilic 
E)  Electrostatic 
A)  Hydrophobic 
B)  Hydrogen 
C)  Disulfide 
D)  Lipophilic 
E)  Electrostatic

Question 20

Which of the following measurements can provide the most information about the overall shape of a protein?

Accepted Answer

A)  Isoelectric point. 
B)  pH of maximum buffering. 
C)  Intrinsic viscosity. 
D)  amino acid composition. 
E)  Ultraviolet absorption. 
A)  Isoelectric point. 
B)  pH of maximum buffering. 
C)  Intrinsic viscosity. 
D)  amino acid composition. 
E)  Ultraviolet absorption.

Exam 3: Protein I: Composition and Structure

What kinds of polypeptide domains are found in native proteins?

Which of the following describes the side chain of glutamine?

Glutamic acid (pK1 = 2.0, pK2 = 4.0, pK3 = 10.0) is dissolved in water. The isoelectric point (pI) of glutamic acid is

All of the following statements regarding collagen are correct EXCEPT which one?

Which of the following mutations would you expect to cause the most drastic alteration in the functional performance of a polypeptide chain? (Assuming the replacement is not at the active site)

Which of the following is not a feature of collagen?

The primary structure of a protein refers to its

The largest part of the driving force causing protein chains to fold into compact, globular structures is typically

In the peptide below, what would be an initial product of the Edman reaction? ala-val-met-glu-ile-trp-ser-cys-glu

What are the characteristics of proteins that are used for separation by 2-D gel electrophoresis in the first and second dimension respectively?

The surface shell of a lipoprotein such as a chylomicron or very low density lipoprotein (VLDL) is composed chiefly of

Which of the following groups of amino acid residues would be expected to have all of their side chains in a charged state at physiological pH?

A protein whose isoelectric point is 5.3 will exhibit minimum solubility at pH

A class of proteins which is distinguished by very low solubility in pure water is the

Protein-protein hydrogen bonding is involved in all of the following structural features in proteins EXCEPT

If two proteins have the same molecular weight then it follows that they also have

amino acid side chains which may be involved in hydrogen bonding in proteins include

Which of the following statements about protein structure is correct?

Which one of the following bonds is LEAST likely to break during protein denaturation?

Which of the following measurements can provide the most information about the overall shape of a protein?

Eukaryotic Cell Structure

DNA and RNA: Composition and Structure

DNA Replication, Recombination, and Repair

RNA: Transcription and Rna Processing

Protein Synthesis: Translation and Posttranslational Modifications

Recombinant Dna and Biotechnology

Regulation of Gene Expression

Protein II: Structure-Function Relationships in Protein Families

Enzymes: Classification, Kinetics, and Control

The Cytochromes P450 and Nitric Oxide Synthases

Biological Membranes: Structure and Membrane Transport

Fundamentals of Signal Transduction

Bioenergetics and Oxidative Metabolism

Carbohydrate Metabolism I: Major Metabolic Pathways and Their Control

Carbohydrate Metabolism II: Special Pathways and Glycoconjugates

Lipid Metabolism I: Synthesis, Storage, and Utilization of Fatty Acids and Triacylglycerols

Lipid Metabolism II: Pathways of Metabolism of Special Lipids

Amino Acid Metabolism

Purine and Pyrimidine Nucleotide Metabolism

Metabolic Interrelationships

Biochemistry of Hormones

Molecular Cell Biology

Cell Cycle, Programmed Cell Death, and Cancer

Digestion and Absorption of Basic Nutritional Constituents

Digestion and Absorption of Basic Nutritional Constituents

Principles of Nutrition I and II

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