Question 1

Two dimensional separation methods

Accepted Answer

A)  lead to unreliable results 
B)  are not widely used because of their complexity 
C)  do not improve separation 
D)  consist of two separation methods applied in sequence 
A)  lead to unreliable results 
B)  are not widely used because of their complexity 
C)  do not improve separation 
D)  consist of two separation methods applied in sequence

Question 2

The typical order for the major steps of enzyme isolation would be (from first to last):

Accepted Answer

A)  Homogenization, salt fractionation, electrophoresis, column chromatography. 
B)  Homogenization, column chromatography, salt fractionation, electrophoresis. 
C)  Homogenization, salt fractionation, column chromatography, electrophoresis. 
D)  Salt fractionation, homogenization, electrophoresis, column chromatography. 
E)  Homogenization, electrophoresis, salt fractionation, column chromatography. 
A)  Homogenization, salt fractionation, electrophoresis, column chromatography. 
B)  Homogenization, column chromatography, salt fractionation, electrophoresis. 
C)  Homogenization, salt fractionation, column chromatography, electrophoresis. 
D)  Salt fractionation, homogenization, electrophoresis, column chromatography. 
E)  Homogenization, electrophoresis, salt fractionation, column chromatography.

Question 3

Which would be best to separate proteins of similar size?

Accepted Answer

A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange 
A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange

Question 4

In an ELISA, the compound 4-chloro-1-naphthol is used because

Accepted Answer

A)  it helps the secondary antibody to bind to the protein 
B)  it helps the primary antibody bind to the protein 
C)  it turns color in the presence of an enzyme that is bound to the secondary antibody 
D)  all of the choices 
A)  it helps the secondary antibody to bind to the protein 
B)  it helps the primary antibody bind to the protein 
C)  it turns color in the presence of an enzyme that is bound to the secondary antibody 
D)  all of the choices

Question 5

Studying how proteins interact with other proteins is called

Accepted Answer

A)  expression proteomics 
B)  structural proteomics 
C)  interaction proteomics 
D)  none of the choices 
A)  expression proteomics 
B)  structural proteomics 
C)  interaction proteomics 
D)  none of the choices

Question 6

Differential centrifugation at low speeds (several thousand RPM) is a useful step when

Accepted Answer

A)  organelles have been lysed. 
B)  enzymes of interest have different sizes. 
C)  cell membranes must be left intact. 
D)  ribosomes need to be broken down. 
E)  there are either organelles or debris to separate. 
A)  organelles have been lysed. 
B)  enzymes of interest have different sizes. 
C)  cell membranes must be left intact. 
D)  ribosomes need to be broken down. 
E)  there are either organelles or debris to separate.

Question 7

Which would be best to separate a protein that binds strongly to its substrate?

Accepted Answer

A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange 
A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange

Question 8

In gel filtration chromatography

Accepted Answer

A)  materials are separated based on their size, the smaller ones eluting first. 
B)  materials are separated based on their size, the larger ones eluting first. 
C)  materials are separated based on their hydrophobic nature, the more hydrophobic ones eluting first. 
D)  materials are separated based on their hydrophobic nature, the less hydrophobic ones eluting first. 
A)  materials are separated based on their size, the smaller ones eluting first. 
B)  materials are separated based on their size, the larger ones eluting first. 
C)  materials are separated based on their hydrophobic nature, the more hydrophobic ones eluting first. 
D)  materials are separated based on their hydrophobic nature, the less hydrophobic ones eluting first.

Question 9

If a protein with the sequence FEWPRQVDMARINE is treated with chymotrypsin, what will the products be?

Accepted Answer

A)  F EW PRQVMARINE 
B)  FE WPRQVD MARINE 
C)  FEWPR QVDMAR INE 
D)  FEWPRQVDM ARINE 
A)  F EW PRQVMARINE 
B)  FE WPRQVD MARINE 
C)  FEWPR QVDMAR INE 
D)  FEWPRQVDM ARINE

Question 10

Generally speaking, sequence techniques have become so sensitive that if you are able to isolate the protein on a gel, there is enough of it to get a significant amount of its sequence.

Accepted Answer

A) True 
 B)False

Question 11

Which would be best to separate positively charged proteins?

Accepted Answer

A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange 
A)  Gel filtration 
B)  Affinity chromatography 
C)  Cation exchange 
D)  Anion exchange 
E)  Cation or anion exchange

Question 12

Which of the following is NOT true concerning a western blot?

Accepted Answer

A)  it is usually performed in a 96 well microtiter plate 
B)  it involves the use of primary antibodies 
C)  it involves the use of secondary antibodies 
D)  it involves electrophoresis 
A)  it is usually performed in a 96 well microtiter plate 
B)  it involves the use of primary antibodies 
C)  it involves the use of secondary antibodies 
D)  it involves electrophoresis

Question 13

Exhibit 5A The following diagram shows the anode, cathode, and pH gradient of an isoelectric focusing bed:   Refer to Exhibit 5A. If the amino acid glycine were placed in the bed where the pH is 11, and the current were turned on, it would migrate closest to which of the following positions?

Accepted Answer

A)  pH 4 
B)  pH 6 
C)  pH 8 
D)  pH 10 
A)  pH 4 
B)  pH 6 
C)  pH 8 
D)  pH 10

Question 14

The typical order of differential centrifugation for organelles is (from slowest speed\lowest g to fastest speed\highest g ):

Accepted Answer

A)  nuclei, microsomes, mitochondria & chloroplasts, cytosol, whole cells 
B)  whole cells, nuclei, mitochondria & chloroplasts, microsomes, cytosol 
C)  cytosol, microsomes, nuclei, mitochondria & chloroplasts, whole cells 
D)  nuclei, mitochondria & chloroplasts, whole cells, cytosol, microsomes 
E)  whole cells, cytosol, microsomes, nuclei, mitochondria & chloroplasts 
A)  nuclei, microsomes, mitochondria & chloroplasts, cytosol, whole cells 
B)  whole cells, nuclei, mitochondria & chloroplasts, microsomes, cytosol 
C)  cytosol, microsomes, nuclei, mitochondria & chloroplasts, whole cells 
D)  nuclei, mitochondria & chloroplasts, whole cells, cytosol, microsomes 
E)  whole cells, cytosol, microsomes, nuclei, mitochondria & chloroplasts

Question 15

An amino acid analyzer is an instrument used to determine

Accepted Answer

A)  the sequence of amino acids in a polypeptide chain 
B)  the identity of N-terminal and C-terminal amino acids in a protein 
C)  the presence of modified amino acids in a protein 
D)  the identities and relative amounts of amino acids in a protein 
A)  the sequence of amino acids in a polypeptide chain 
B)  the identity of N-terminal and C-terminal amino acids in a protein 
C)  the presence of modified amino acids in a protein 
D)  the identities and relative amounts of amino acids in a protein

Question 16

In the SDS-PAGE (sodium dodecylsulfate - polyacrylamide gel electrophoresis) method, separation takes place on the basis of

Accepted Answer

A)  charge only, because all particles have different charges, but the same mass. 
B)  the sieving action of the gel, because all particles have the same charge, but different masses. 
C)  the sieving action of the gel, because all particles have approximately the same charge\mass ratio, but different masses. 
D)  the chemical nature of the buffer used as the electrolyte. 
A)  charge only, because all particles have different charges, but the same mass. 
B)  the sieving action of the gel, because all particles have the same charge, but different masses. 
C)  the sieving action of the gel, because all particles have approximately the same charge\mass ratio, but different masses. 
D)  the chemical nature of the buffer used as the electrolyte.

Question 17

Using differential centrifugation it is possible to separate

Accepted Answer

A)  nuclei, mitochondria, and ribosomes into three separate fractions 
B)  organelles from contaminating salts 
C)  proteins that differ in charge 
D)  proteins from membranes 
A)  nuclei, mitochondria, and ribosomes into three separate fractions 
B)  organelles from contaminating salts 
C)  proteins that differ in charge 
D)  proteins from membranes

Question 18

Cyanogen bromide (CNBr) cleaves proteins

Accepted Answer

A)  after positively charged residues, such as K & R. 
B)  after negatively charged residues, such as D & E. 
C)  after aromatic residues, such as Y & W. 
D)  after methionine residues. 
A)  after positively charged residues, such as K & R. 
B)  after negatively charged residues, such as D & E. 
C)  after aromatic residues, such as Y & W. 
D)  after methionine residues.

Question 19

Which of the following is not used in protein structure determination?

Accepted Answer

A)  digestion with proteolytic enzymes 
B)  the Edman method 
C)  treatment with cyanogen bromide 
D)  treatment with alkyl halides 
A)  digestion with proteolytic enzymes 
B)  the Edman method 
C)  treatment with cyanogen bromide 
D)  treatment with alkyl halides

Question 20

The purity of an enzyme at various stages of purification is best measured by

Accepted Answer

A)  total protein. 
B)  total enzyme activity. 
C)  specific activity of the enzyme. 
D)  percent recovery of the protein. 
E)  percent recovery of the enzyme. 
A)  total protein. 
B)  total enzyme activity. 
C)  specific activity of the enzyme. 
D)  percent recovery of the protein. 
E)  percent recovery of the enzyme.

Exam 5: Protein Purification and Characterization Techniques

Two dimensional separation methods

The typical order for the major steps of enzyme isolation would be (from first to last):

Which would be best to separate proteins of similar size?

In an ELISA, the compound 4-chloro-1-naphthol is used because

Studying how proteins interact with other proteins is called

Differential centrifugation at low speeds (several thousand RPM) is a useful step when

Which would be best to separate a protein that binds strongly to its substrate?

In gel filtration chromatography

If a protein with the sequence FEWPRQVDMARINE is treated with chymotrypsin, what will the products be?

Generally speaking, sequence techniques have become so sensitive that if you are able to isolate the protein on a gel, there is enough of it to get a significant amount of its sequence.

Which would be best to separate positively charged proteins?

Which of the following is NOT true concerning a western blot?

Exhibit 5A The following diagram shows the anode, cathode, and pH gradient of an isoelectric focusing bed: Refer to Exhibit 5A. If the amino acid glycine were placed in the bed where the pH is 11, and the current were turned on, it would migrate closest to which of the following positions?

The typical order of differential centrifugation for organelles is (from slowest speed\lowest g to fastest speed\highest g ):

An amino acid analyzer is an instrument used to determine

In the SDS-PAGE (sodium dodecylsulfate - polyacrylamide gel electrophoresis) method, separation takes place on the basis of

Using differential centrifugation it is possible to separate

Cyanogen bromide (CNBr) cleaves proteins

Which of the following is not used in protein structure determination?

The purity of an enzyme at various stages of purification is best measured by

Biochemistry and the Organization of Cells

Water the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three Dimensional Structure of Proteins

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

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