Question 1

Fibroin is a β-sheet protein, with a high proportion of glycine.

Accepted Answer

A) True 
 B)False  True

Question 2

SDS gel electrophoresis can be used to determine:

Accepted Answer

A)  whether subunits in a protein complex are identical or not. 
B)  the molecular mass of a native protein complex. 
C)  the overall charge on a polypeptide. 
D)  the molecular mass of denatured protein subunits. 
E)  none of the above. 
A)  whether subunits in a protein complex are identical or not. 
B)  the molecular mass of a native protein complex. 
C)  the overall charge on a polypeptide. 
D)  the molecular mass of denatured protein subunits. 
E)  none of the above. D

Question 3

The folded conformation of proteins can be stabilized by the binding of a metal ion or cofactor.

Accepted Answer

A) True 
 B)False  True

Question 4

Protein folding is a thermodynamically favorable process under physiological conditions because:

Accepted Answer

A)  there is an increase in entropy associated with protein folding. 
B)  there is a decrease in entropy of the solvent by burying hydrophobic groups within the molecule. 
C)  of the large negative enthalpy change associated with many noncovalent interactions. 
D)  no intermediate stage disulphide bonds form during the folding process. 
E)  all of the above. 
A)  there is an increase in entropy associated with protein folding. 
B)  there is a decrease in entropy of the solvent by burying hydrophobic groups within the molecule. 
C)  of the large negative enthalpy change associated with many noncovalent interactions. 
D)  no intermediate stage disulphide bonds form during the folding process. 
E)  all of the above.

Question 5

In considering protein secondary structure which of the following is INCORRECT?

Accepted Answer

A)  An α helix repeats after 18 residues and has 3.6 residues per turn. 
B)  A network of main-chain hydrogen bonds connect β strands in a β sheet. 
C)  The most common structures are the α helix and the β sheet. 
D)  The 310 helix is right-handed and often contains proline residues. 
E)  The β strands can be in either parallel or antiparallel configuration. 
A)  An α helix repeats after 18 residues and has 3.6 residues per turn. 
B)  A network of main-chain hydrogen bonds connect β strands in a β sheet. 
C)  The most common structures are the α helix and the β sheet. 
D)  The 310 helix is right-handed and often contains proline residues. 
E)  The β strands can be in either parallel or antiparallel configuration.

Question 6

Tropocollagen is a double helix of two left-handed polypeptide chains.

Accepted Answer

A) True 
 B)False

Question 7

The protein that makes up about a third of the total protein mass in animals is:

Accepted Answer

A)  β-keratin. 
B)  collagen. 
C)  hemoglobin. 
D)  myoglobin. 
E)  α-keratin. 
A)  β-keratin. 
B)  collagen. 
C)  hemoglobin. 
D)  myoglobin. 
E)  α-keratin.

Question 8

________ between amide protons and carbonyl oxygens is necessary to stabilize a regular folding of protein secondary structure.

Accepted Answer

The answer of ________ between amide protons and carbonyl oxygens...

Question 9

The interactions that stabilize multisubunit complexes are different to those that stabilize tertiary structure.

Accepted Answer

A) True 
 B)False

Question 10

The cavity in the GroEL-GroES complex from E. coli provides a favorable environment that prevents ________ and mis-folding.

Accepted Answer

The answer of The cavity in the GroEL-GroES complex from...

Question 11

Protein folding is a random process, whereby a vast number of possible conformations are tested to find the desired most stable state.

Accepted Answer

A) True 
 B)False

Question 12

Which of the following statements about α-keratins is FALSE?

Accepted Answer

A)  They include a major class of protein that comprises hair, fingernails and animal skin. 
B)  Individual molecules are α-helical. 
C)  There is a strip of contiguous hydrophobic surface making a shallow spiral around the helix. 
D)  They include a small globular regions covalently linked to the surface. 
E)  Pairs of α-helices twist about each other in a coiled-coil structure held together entirely by hydrophobic interactions. 
A)  They include a major class of protein that comprises hair, fingernails and animal skin. 
B)  Individual molecules are α-helical. 
C)  There is a strip of contiguous hydrophobic surface making a shallow spiral around the helix. 
D)  They include a small globular regions covalently linked to the surface. 
E)  Pairs of α-helices twist about each other in a coiled-coil structure held together entirely by hydrophobic interactions.

Question 13

A ________ plot describes which structures in a polypeptide are sterically possible and which are not based on the angles of rotation about the backbone Namide -Cα and Cα-Ccarbonyl bonds.

Accepted Answer

The answer of A ________ plot describes which structures in...

Question 14

Which of the following is CORRECT when considering the tertiary structure of globular proteins?

Accepted Answer

A)  β sheets are usually twisted or wrapped into barrel structures. 
B)  Hydrophobic residues are normally on the inside and hydrophilic residues are on the outside. 
C)  The amino acid proline never occurs in a region where the polypeptide chain bends or turns. 
D)  All parts of the proteins can be classified as helix, β sheet or turns. 
E)  None of the above. 
A)  β sheets are usually twisted or wrapped into barrel structures. 
B)  Hydrophobic residues are normally on the inside and hydrophilic residues are on the outside. 
C)  The amino acid proline never occurs in a region where the polypeptide chain bends or turns. 
D)  All parts of the proteins can be classified as helix, β sheet or turns. 
E)  None of the above.

Question 15

The functional organization of proteins where specific complexes of two or more polypeptides are formed is called ________ structure.

Accepted Answer

The answer of The functional organization of proteins where specific...

Question 16

Which technique is able to investigate secondary structural features of proteins?

Accepted Answer

A)  Infrared spectroscopy 
B)  Ultraviolet spectroscopy 
C)  Fluorescence spectroscopy 
D)  Circular dichroism 
E)  All of the above 
A)  Infrared spectroscopy 
B)  Ultraviolet spectroscopy 
C)  Fluorescence spectroscopy 
D)  Circular dichroism 
E)  All of the above

Question 17

Bovine spongiform encephalopathy is an infectious disease caused by a prion protein, which undergoes a ________ change to become pathogenic.

Accepted Answer

The answer of Bovine spongiform encephalopathy is an infectious disease...

Question 18

Proteins cannot self-assemble into a functional conformation after they have been denatured.

Accepted Answer

A) True 
 B)False

Question 19

Scurvy results in weakness in collagen fibres because the enzymes that catalyze ________ of proline and lysine residues in collagen require Vitamin C.

Accepted Answer

The answer of Scurvy results in weakness in collagen fibres...

Question 20

________ spectroscopy can be used to study dynamic processes in solution.

Accepted Answer

Nuclear ma

Exam 6: The Three-Dimensional Structure of Proteins

Fibroin is a β-sheet protein, with a high proportion of glycine.

SDS gel electrophoresis can be used to determine:

The folded conformation of proteins can be stabilized by the binding of a metal ion or cofactor.

Protein folding is a thermodynamically favorable process under physiological conditions because:

In considering protein secondary structure which of the following is INCORRECT?

Tropocollagen is a double helix of two left-handed polypeptide chains.

The protein that makes up about a third of the total protein mass in animals is:

________ between amide protons and carbonyl oxygens is necessary to stabilize a regular folding of protein secondary structure.

The interactions that stabilize multisubunit complexes are different to those that stabilize tertiary structure.

The cavity in the GroEL-GroES complex from E. coli provides a favorable environment that prevents ________ and mis-folding.

Protein folding is a random process, whereby a vast number of possible conformations are tested to find the desired most stable state.

Which of the following statements about α-keratins is FALSE?

A ________ plot describes which structures in a polypeptide are sterically possible and which are not based on the angles of rotation about the backbone Namide -Cα and Cα-Ccarbonyl bonds.

Which of the following is CORRECT when considering the tertiary structure of globular proteins?

The functional organization of proteins where specific complexes of two or more polypeptides are formed is called ________ structure.

Which technique is able to investigate secondary structural features of proteins?

Bovine spongiform encephalopathy is an infectious disease caused by a prion protein, which undergoes a ________ change to become pathogenic.

Proteins cannot self-assemble into a functional conformation after they have been denatured.

Scurvy results in weakness in collagen fibres because the enzymes that catalyze ________ of proline and lysine residues in collagen require Vitamin C.

________ spectroscopy can be used to study dynamic processes in solution.

Biochemistry and the Language of Chemistry

The Chemical Foundation of Life: Weak Interactions in an Aqueous Environment

The Energetics of Life

Nucleic Acids

Introduction to Proteins: the Primary Level of Protein Structure

Protein Function and Evolution

Enzymes: Biological Catalysts

Carbohydrates: Sugars, Saccharides, Glycans

Lipids, Membranes, and Cellular Transport

Chemical Logic of Metabolism

Carbohydrate Metabolism: Glycolysis, Gluconeogenesis, Glycogen Metabolism, and the Pentose Phosphate Pathway

The Citric Acid Cycle

Electron Transport, Oxidative Phosphorylation, and Oxygen Metabolism

Photosynthesis

Lipid Metabolism

Interorgan and Intracellular Coordination of Energy Metabolism in Vertebrates

Amino Acid and Nitrogen Metabolism

Nucleotide Metabolism

Mechanisms of Signal Transduction

Genes, Genomes, and Chromosomes

DNA Replication

DNA Repair, Recombination, and Rearrangement

Transcription and Post-Transcriptional Processing

Information Decoding: Translation and Post-Translational Protein Processing

Regulation of Gene Expression

Filters