Question 1

The tertiary structure of a protein is usually a result of which of the following interactions?

Accepted Answer

A)  intramolecular hydrogen bonding 
B)  electrostatic interactions 
C)  hydrophobic interactions 
D)  all of these 
A)  intramolecular hydrogen bonding 
B)  electrostatic interactions 
C)  hydrophobic interactions 
D)  all of these

Question 2

Which of the following best defines a domain?

Accepted Answer

A)  A supersecondary region, often shared by proteins, that has a specific function. 
B)  A repetitive supersecondary structure. 
C)  A double-layered arrangement formed so that the polar groups face the aqueous environment, while the nonpolar regions are kept away from the aqueous environment. 
D)  An unfolded region of a protein. 
A)  A supersecondary region, often shared by proteins, that has a specific function. 
B)  A repetitive supersecondary structure. 
C)  A double-layered arrangement formed so that the polar groups face the aqueous environment, while the nonpolar regions are kept away from the aqueous environment. 
D)  An unfolded region of a protein.

Question 3

Which of the following statements regarding hemoglobin (Hb) and myoglobin (Mb) is true?

Accepted Answer

A)  Mb transports oxygen while Hb stores it. 
B)  Mb has quaternary structure but Hb does not. 
C)  Mb displays simple kinetics of binding while Hb displays cooperativity. 
D)  Mb binds Fe(II) while Hb binds heme. 
A)  Mb transports oxygen while Hb stores it. 
B)  Mb has quaternary structure but Hb does not. 
C)  Mb displays simple kinetics of binding while Hb displays cooperativity. 
D)  Mb binds Fe(II) while Hb binds heme.

Question 4

Exhibit 4B   Refer to Exhibit 4B. The type of bonding labeled "N" in these figure is:

Accepted Answer

A)  Hydrogen bonding of the peptide backbone 
B)  Covalent bonding involving the R-groups 
C)  Hydrophobic interactions 
D)  Metal ion coordination 
E)  Electrostatic attraction 
A)  Hydrogen bonding of the peptide backbone 
B)  Covalent bonding involving the R-groups 
C)  Hydrophobic interactions 
D)  Metal ion coordination 
E)  Electrostatic attraction

Question 5

Which of the following proteins is not homologous with the others?

Accepted Answer

A)  myoglogin 
B)  α -chain of hemoglobin 
C)  β -chain of hemoglobin 
D)  collagen 
A)  myoglogin 
B)  α -chain of hemoglobin 
C)  β -chain of hemoglobin 
D)  collagen

Question 6

Under normal circumstances:

Accepted Answer

A)  Adult Hb binds to oxygen more tightly than Mb binds. 
B)  Fetal Hb binds oxygen more tightly than adult Hb. 
C)  Adult Hb binds oxygen more tightly than either fetal Hb or Mb binds. 
D)  Mb has the lowest affinity for oxygen of the 3. 
E)  More than one of these statements is correct. 
A)  Adult Hb binds to oxygen more tightly than Mb binds. 
B)  Fetal Hb binds oxygen more tightly than adult Hb. 
C)  Adult Hb binds oxygen more tightly than either fetal Hb or Mb binds. 
D)  Mb has the lowest affinity for oxygen of the 3. 
E)  More than one of these statements is correct.

Question 7

In allosteric interactions

Accepted Answer

A)  proteins that consist of a single polypeptide chain form aggregates. 
B)  disulfide bonds are broken. 
C)  changes that take place in one site of a protein cause changes at a distant site. 
D)  metal ions always bind to the protein. 
A)  proteins that consist of a single polypeptide chain form aggregates. 
B)  disulfide bonds are broken. 
C)  changes that take place in one site of a protein cause changes at a distant site. 
D)  metal ions always bind to the protein.

Question 8

The following bond forces are important in tertiary structure:

Accepted Answer

A)  Disulfide bonds 
B)  Hydrogen bonds 
C)  Hydrophobic attraction 
D)  Both hydrogen bonds and hydrophobic attraction. 
E)  All of these are important in tertiary structure 
A)  Disulfide bonds 
B)  Hydrogen bonds 
C)  Hydrophobic attraction 
D)  Both hydrogen bonds and hydrophobic attraction. 
E)  All of these are important in tertiary structure

Question 9

Exhibit 4A The following question(s) refer to this peptide:
Cys-Ala-Gly-Arg-Gln-Met
Refer to Exhibit 4A. The amino terminal amino acid is:

Accepted Answer

A)  Arg 
B)  Cys 
C)  Gln 
D)  Met 
E)  None of these. 
A)  Arg 
B)  Cys 
C)  Gln 
D)  Met 
E)  None of these.

Question 10

Which of the following best describes a motif?

Accepted Answer

A)  a repetitive supersecondary structure 
B)  a common nonrepetitive irregularity found in antiparallel β -sheets 
C)  a protein conformation with biological activity 
D)  a group of atoms other than an amino acid 
A)  a repetitive supersecondary structure 
B)  a common nonrepetitive irregularity found in antiparallel β -sheets 
C)  a protein conformation with biological activity 
D)  a group of atoms other than an amino acid

Question 11

The following is true about the hydroxyproline in collagen:

Accepted Answer

A)  Hydroxyproline is incorporated into the chain during polymerization of amino acids. 
B)  Vitamin C is necessary for the synthesis of hydroxyproline. 
C)  Hydroxyproline is important in holding the 3 strands of collagen together. 
D)  Hydroxyproline requires Vitamin C for its synthesis and it holds the collagen helix together. 
E)  All of these. 
A)  Hydroxyproline is incorporated into the chain during polymerization of amino acids. 
B)  Vitamin C is necessary for the synthesis of hydroxyproline. 
C)  Hydroxyproline is important in holding the 3 strands of collagen together. 
D)  Hydroxyproline requires Vitamin C for its synthesis and it holds the collagen helix together. 
E)  All of these.

Question 12

_____ are natural glycoproteins found in the cell membranes of nerve tissues and are known to cause spongiform encephalopathy in humans.

Accepted Answer

A)  Viroids 
B)  Actin-binding proteins 
C)  Alpha-fetoproteins 
D)  Prions 
A)  Viroids 
B)  Actin-binding proteins 
C)  Alpha-fetoproteins 
D)  Prions

Question 13

​ Identify the portion of proteins that does not consist of amino acids.

Accepted Answer

A)  Subunit 
B)  Prosthetic group 
C)  Domain 
D)  Motif 
A)  Subunit 
B)  Prosthetic group 
C)  Domain 
D)  Motif

Question 14

The oxygen binding curve of which of the following is the closest to that of myoglobin?

Accepted Answer

A)  hemoglobin at pH 6.8 
B)  hemoglobin that lacks BPG 
C)  maternal hemoglobin 
D)  fetal hemoglobin 
A)  hemoglobin at pH 6.8 
B)  hemoglobin that lacks BPG 
C)  maternal hemoglobin 
D)  fetal hemoglobin

Question 15

Which one is not an example of supersecondary structure?

Accepted Answer

A)  the pyrrole ring 
B)  the Greek key 
C)  the β -meander 
D)  the β -barrel 
A)  the pyrrole ring 
B)  the Greek key 
C)  the β -meander 
D)  the β -barrel

Question 16

The Bohr effect for oxygen binding states that

Accepted Answer

A)  Mb binds oxygen more tightly than Hb. 
B)  Hb will bind oxygen very tightly when the CO2 concentration is high. 
C)  as the pH goes down, Hb binds oxygen less tightly. 
D)  Hb's ability to bind oxygen increases with higher oxygen concentration. 
A)  Mb binds oxygen more tightly than Hb. 
B)  Hb will bind oxygen very tightly when the CO2 concentration is high. 
C)  as the pH goes down, Hb binds oxygen less tightly. 
D)  Hb's ability to bind oxygen increases with higher oxygen concentration.

Question 17

The following bond forces are important in quaternary structure:

Accepted Answer

A)  Disulfide bonds 
B)  Hydrogen bonds 
C)  Hydrophobic attraction 
D)  Both hydrogen bonds and hydrophobic attraction. 
E)  All of these are important in quaternary structure. 
A)  Disulfide bonds 
B)  Hydrogen bonds 
C)  Hydrophobic attraction 
D)  Both hydrogen bonds and hydrophobic attraction. 
E)  All of these are important in quaternary structure.

Question 18

Which of the following statements regarding hydrogen bonding in secondary structures is true ?

Accepted Answer

A)  Both α -helices and β -sheets only use intrachain hydrogen bonds. 
B)  Both α -helices and β -sheets only use interchain hydrogen bonds. 
C)  α -helices only use intrachain hydrogen bonds and β -sheets can use either intrachain or interchain hydrogen bonds. 
D)  α -helices can use either intrachain or interchain hydrogen bonds and β -sheets only use interchain hydrogen bonds. 
A)  Both α -helices and β -sheets only use intrachain hydrogen bonds. 
B)  Both α -helices and β -sheets only use interchain hydrogen bonds. 
C)  α -helices only use intrachain hydrogen bonds and β -sheets can use either intrachain or interchain hydrogen bonds. 
D)  α -helices can use either intrachain or interchain hydrogen bonds and β -sheets only use interchain hydrogen bonds.

Question 19

Which of the following is true?

Accepted Answer

A)  The peptide bonds in the β -sheet are extended. 
B)  The peptide bonds in the α -helix coil back on themselves. 
C)  Both α -helices and β -sheets can be found as part of tertiary structure. 
D)  All of these 
A)  The peptide bonds in the β -sheet are extended. 
B)  The peptide bonds in the α -helix coil back on themselves. 
C)  Both α -helices and β -sheets can be found as part of tertiary structure. 
D)  All of these

Question 20

Exhibit 4A The following question(s) refer to this peptide:
Cys-Ala-Gly-Arg-Gln-Met
Refer to Exhibit 4A. The carboxyl terminal end is:

Accepted Answer

A)  Arg 
B)  Cys 
C)  Gln 
D)  Met 
E)  None of these. 
A)  Arg 
B)  Cys 
C)  Gln 
D)  Met 
E)  None of these.

Exam 4: The Three Dimensional Structure of Proteins

The tertiary structure of a protein is usually a result of which of the following interactions?

Which of the following best defines a domain?

Which of the following statements regarding hemoglobin (Hb) and myoglobin (Mb) is true?

Exhibit 4B Refer to Exhibit 4B. The type of bonding labeled "N" in these figure is:

Which of the following proteins is not homologous with the others?

Under normal circumstances:

In allosteric interactions

The following bond forces are important in tertiary structure:

Exhibit 4A The following question(s) refer to this peptide: Cys-Ala-Gly-Arg-Gln-Met Refer to Exhibit 4A. The amino terminal amino acid is:

Which of the following best describes a motif?

The following is true about the hydroxyproline in collagen:

_____ are natural glycoproteins found in the cell membranes of nerve tissues and are known to cause spongiform encephalopathy in humans.

​ Identify the portion of proteins that does not consist of amino acids.

The oxygen binding curve of which of the following is the closest to that of myoglobin?

Which one is not an example of supersecondary structure?

The Bohr effect for oxygen binding states that

The following bond forces are important in quaternary structure:

Which of the following statements regarding hydrogen bonding in secondary structures is true ?

Which of the following is true?

Exhibit 4A The following question(s) refer to this peptide: Cys-Ala-Gly-Arg-Gln-Met Refer to Exhibit 4A. The carboxyl terminal end is:

Biochemistry and the Organization of Cells

Water the Solvent for Biochemical Reactions

Amino Acids and Peptides

Protein Purification and Characterization Techniques

The Behavior of Proteins Enzymes

The Behavior of Proteins Enzymes Mechanisms and Control

Lipids and Proteins Are Associated in Biological Membranes

Nucleic Acids How Structure Conveys Information

Biosynthesis of Nucleic Acids Replication

Transcription of the Genetic Code the Biosynthesis of Rna

Protein Synthesis Translation of the Genetic Message

Nucleic Acid Biotechnology Techniques

Viruses Cancer and Immunology

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism Cellular Signaling

Filters

Identify the portion of proteins that does not consist of amino acids.