Question 1

Protein separation techniques which utilize differences in charge between proteins in a mixture are:

Accepted Answer

A)  Carboxymethyl (CM) chromatography 
B)  Affinity chromatography 
C)  Isoelectric focusing 
D)  A and B 
E)  A and C 
A)  Carboxymethyl (CM) chromatography 
B)  Affinity chromatography 
C)  Isoelectric focusing 
D)  A and B 
E)  A and C

Question 2

Part of the structure of collagen consists of

Accepted Answer

A)  a triple helix. 
B)  an alpha-helical coil. 
C)  anti-parallel beta-sheets. 
D)  extensive disulfide bond cross-linking. 
E)  parallel beta-sheets. 
A)  a triple helix. 
B)  an alpha-helical coil. 
C)  anti-parallel beta-sheets. 
D)  extensive disulfide bond cross-linking. 
E)  parallel beta-sheets.

Question 3

Desmosine, the unusual crosslinking amino acid found in elastin, is formed from

Accepted Answer

A)  hydroxylysine. 
B)  proline. 
C)  lysine. 
D)  aspartate. 
E)  arginine. 
A)  hydroxylysine. 
B)  proline. 
C)  lysine. 
D)  aspartate. 
E)  arginine.

Question 4

Primary sequences of proteins are determined mainly by

Accepted Answer

A)  sequential degradation. 
B)  X-ray diffraction. 
C)  ultracentrifugation. 
D)  synthesis. 
E)  amino acid analysis. 
A)  sequential degradation. 
B)  X-ray diffraction. 
C)  ultracentrifugation. 
D)  synthesis. 
E)  amino acid analysis.

Question 5

An essential element of the alpha-helical structure of proteins is

Accepted Answer

A)  disulfide bonds. 
B)  hydrogen bonds perpendicular to the axis. 
C)  salt links. 
D)  hydrogen bonds randomly placed. 
E)  hydrogen bonds parallel to the axis. 
A)  disulfide bonds. 
B)  hydrogen bonds perpendicular to the axis. 
C)  salt links. 
D)  hydrogen bonds randomly placed. 
E)  hydrogen bonds parallel to the axis.

Question 6

All of the following amino acids are optically active EXCEPT

Accepted Answer

A)  Leucine. 
B)  Alanine. 
C)  Glycine. 
D)  Cysteine. 
E)  Lysine. 
A)  Leucine. 
B)  Alanine. 
C)  Glycine. 
D)  Cysteine. 
E)  Lysine.

Question 7

Which statement below is most correct regarding the alpha helical structure of polypeptide chains in proteins?

Accepted Answer

A)  It is primarily dependent upon hydrogen bonding. 
B)  It is primarily dependent upon disulfide linkages. 
C)  It is found in all proteins. 
D)  It refers to interactions between adjacent chains in fibrous proteins. 
A)  It is primarily dependent upon hydrogen bonding. 
B)  It is primarily dependent upon disulfide linkages. 
C)  It is found in all proteins. 
D)  It refers to interactions between adjacent chains in fibrous proteins.

Question 8

To which of the following does protein tertiary structure refer?

Accepted Answer

A)  amino acid sequence 
B)  amino acid composition 
C)  helical structure in proteins 
D)  the bonding of the protein to nonprotein components 
E)  the three dimensional structure 
A)  amino acid sequence 
B)  amino acid composition 
C)  helical structure in proteins 
D)  the bonding of the protein to nonprotein components 
E)  the three dimensional structure

Question 9

Soluble globular proteins are folded so that

Accepted Answer

A)  most hydrophobic amino acids are internal, away from solvent water. 
B)  the free energy of the system (protein + water) is at a maximum. 
C)  most hydrophilic amino acid residues are protected from water. 
D)  Two of the above are true. 
E)  All of the above are true. 
A)  most hydrophobic amino acids are internal, away from solvent water. 
B)  the free energy of the system (protein + water) is at a maximum. 
C)  most hydrophilic amino acid residues are protected from water. 
D)  Two of the above are true. 
E)  All of the above are true.

Question 10

Stability of secondary structures within a protein is a result of

Accepted Answer

A)  disulfide bonds between Cys residues. 
B)  electrostatic bonds between Glu and Lys side chains. 
C)  hydrogen bonds between backbone atoms. 
D)  post_translational modifications to selected amino acids. 
E)  stacking of aromatic side chains. 
A)  disulfide bonds between Cys residues. 
B)  electrostatic bonds between Glu and Lys side chains. 
C)  hydrogen bonds between backbone atoms. 
D)  post_translational modifications to selected amino acids. 
E)  stacking of aromatic side chains.

Question 11

All of the following generalizations are correct with regard to the overall structure of a protein EXCEPT which one?

Accepted Answer

A)  amino acid residues on the surface of the protein are polar. 
B)  amino acid residues in the interior are hydrophobic. 
C)  Charged amino acids on the protein interact with ions in the environment. 
D)  The alpha-helix or the pleated sheet is present in most proteins. 
E)  Hydrogen bonds in the peptide backbone play a minor role in the structure of the protein. 
A)  amino acid residues on the surface of the protein are polar. 
B)  amino acid residues in the interior are hydrophobic. 
C)  Charged amino acids on the protein interact with ions in the environment. 
D)  The alpha-helix or the pleated sheet is present in most proteins. 
E)  Hydrogen bonds in the peptide backbone play a minor role in the structure of the protein.

Question 12

Which interaction may participate in the stabilization of tertiary structure by covalently linking different polypeptide chains?

Accepted Answer

A)  disulfide bond 
B)  electrostatic interaction 
C)  hydrogen bond 
D)  hydrophobic interaction 
E)  peptide bond 
A)  disulfide bond 
B)  electrostatic interaction 
C)  hydrogen bond 
D)  hydrophobic interaction 
E)  peptide bond

Question 13

Which of the following amino acid residues may participate in strong hydrophobic bonding?

Accepted Answer

A)  Glycine. 
B)  Isoleucine. 
C)  Lysine. 
D)  Serine. 
E)  Aspartate. 
A)  Glycine. 
B)  Isoleucine. 
C)  Lysine. 
D)  Serine. 
E)  Aspartate.

Question 14

Which amino acid contains a sulfur atom?

Accepted Answer

A)  Arginine 
B)  Aspartate 
C)  Methionine 
D)  Leucine 
E)  Serine 
A)  Arginine 
B)  Aspartate 
C)  Methionine 
D)  Leucine 
E)  Serine

Question 15

When a protein has alpha-helical structure, how many amino acid residues are there per turn of the helix?

Accepted Answer

A)  2.6 
B)  3.2 
C)  3.6 
D)  4.2 
E)  none of the above 
A)  2.6 
B)  3.2 
C)  3.6 
D)  4.2 
E)  none of the above

Question 16

The following protein separation techniques take advantage of the charge differences between various proteins EXCEPT for:

Accepted Answer

A)  Diethylaminoethyl (DEA
E)  chromatography 
B)  Two dimensional gel electrophoresis 
C)  Isoelectric focusing 
D)  Gel filtration chromatography 
A)  Diethylaminoethyl (DEA
E)  chromatography 
B)  Two dimensional gel electrophoresis 
C)  Isoelectric focusing 
D)  Gel filtration chromatography

Question 17

All of the following are involved as factors governing the folding of a protein EXCEPT which one?

Accepted Answer

A)  Hydrogen bonds between groups involved in peptide bonding. 
B)  Hydrogen bonds between amino acid side chains. 
C)  Electrostatic interactions. 
D)  Hydrophobic bonding. 
E)  They are all involved. 
A)  Hydrogen bonds between groups involved in peptide bonding. 
B)  Hydrogen bonds between amino acid side chains. 
C)  Electrostatic interactions. 
D)  Hydrophobic bonding. 
E)  They are all involved.

Question 18

In the native form of a simple, globular protein in aqueous solution, the charged groups:

Accepted Answer

A)  have pK's below the solution pH 
B)  are mostly involved in intramolecular electrostatic bonds. 
C)  are almost all on the surface of the molecule. 
D)  are completely accounted for by the side chains of the basic and acidic amino acids. 
E)  All of the above. 
A)  have pK's below the solution pH 
B)  are mostly involved in intramolecular electrostatic bonds. 
C)  are almost all on the surface of the molecule. 
D)  are completely accounted for by the side chains of the basic and acidic amino acids. 
E)  All of the above.

Question 19

Edman degradation refers to

Accepted Answer

A)  a metabolic pathway for catabolism of proteins. 
B)  a chemical method for determination of the N-terminal amino acid sequence of proteins and polypeptides. 
C)  an enzymatic method for determination of the C-terminal sequence of proteins and polypeptides. 
D)  a chemical method for determination of the C-terminal sequence of proteins and polypeptides. 
E)  None of the above statements correctly refer to the Edman degradation. 
A)  a metabolic pathway for catabolism of proteins. 
B)  a chemical method for determination of the N-terminal amino acid sequence of proteins and polypeptides. 
C)  an enzymatic method for determination of the C-terminal sequence of proteins and polypeptides. 
D)  a chemical method for determination of the C-terminal sequence of proteins and polypeptides. 
E)  None of the above statements correctly refer to the Edman degradation.

Question 20

Secondary structure of proteins

Accepted Answer

A)  is maintained by hydrogen bonds. 
B)  refers to proteins consisting of two (or more) subunits held together by noncovalent forces. 
C)  encompasses any hydrogen-bonded interaction found in proteins. 
D)  refers to proteins consisting of one or more polypeptide chains plus a nonprotein moiety. 
E)  is found only in fibrous proteins. 
A)  is maintained by hydrogen bonds. 
B)  refers to proteins consisting of two (or more) subunits held together by noncovalent forces. 
C)  encompasses any hydrogen-bonded interaction found in proteins. 
D)  refers to proteins consisting of one or more polypeptide chains plus a nonprotein moiety. 
E)  is found only in fibrous proteins.

Exam 3: Protein I: Composition and Structure

Protein separation techniques which utilize differences in charge between proteins in a mixture are:

Part of the structure of collagen consists of

Desmosine, the unusual crosslinking amino acid found in elastin, is formed from

Primary sequences of proteins are determined mainly by

An essential element of the alpha-helical structure of proteins is

All of the following amino acids are optically active EXCEPT

Which statement below is most correct regarding the alpha helical structure of polypeptide chains in proteins?

To which of the following does protein tertiary structure refer?

Soluble globular proteins are folded so that

Stability of secondary structures within a protein is a result of

All of the following generalizations are correct with regard to the overall structure of a protein EXCEPT which one?

Which interaction may participate in the stabilization of tertiary structure by covalently linking different polypeptide chains?

Which of the following amino acid residues may participate in strong hydrophobic bonding?

Which amino acid contains a sulfur atom?

When a protein has alpha-helical structure, how many amino acid residues are there per turn of the helix?

The following protein separation techniques take advantage of the charge differences between various proteins EXCEPT for:

All of the following are involved as factors governing the folding of a protein EXCEPT which one?

In the native form of a simple, globular protein in aqueous solution, the charged groups:

Edman degradation refers to

Secondary structure of proteins

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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