Question 1

Which of the following participates in the reaction at the catalytic site of chymotrypsin?

Accepted Answer

A)  amino ethanol 
B)  urea 
C)  pyridoxal 
D)  serine 
E)  mercaptoethanol 
A)  amino ethanol 
B)  urea 
C)  pyridoxal 
D)  serine 
E)  mercaptoethanol

Question 2

Which of the following results in a shift of the oxyhemoglobin dissociation curve to the right?

Accepted Answer

A)  An increase in 2,3-BPG 
B)  A decrease in temperature 
C)  An increase in pH 
D)  A decrease in PC02 
A)  An increase in 2,3-BPG 
B)  A decrease in temperature 
C)  An increase in pH 
D)  A decrease in PC02

Question 3

Which of the following regarding 2,3-BPG is correct?

Accepted Answer

A)  Increasing 2,3-BPG concentration shifts the oxyhemoglobin dissociation curve to the right. 
B)  It binds to the alpha-chains in the core of the hemoglobin molecule. 
C)  It responds rapidly to hypoxia 
D)  It increases the affinity of hemoglobin for oxygen 
A)  Increasing 2,3-BPG concentration shifts the oxyhemoglobin dissociation curve to the right. 
B)  It binds to the alpha-chains in the core of the hemoglobin molecule. 
C)  It responds rapidly to hypoxia 
D)  It increases the affinity of hemoglobin for oxygen

Question 4

Similarities between hemoglobin and myoglobin include:

Accepted Answer

A)  heme as a prosthetic group. 
B)  the effects of pH on oxygen binding. 
C)  the effects of BPG. 
D)  the shape of the oxygen dissociation curve. 
E)  conversion from tense to relaxed conformation at increased PO2. 
A)  heme as a prosthetic group. 
B)  the effects of pH on oxygen binding. 
C)  the effects of BPG. 
D)  the shape of the oxygen dissociation curve. 
E)  conversion from tense to relaxed conformation at increased PO2.

Question 5

The primary function of an antibody has been fulfilled when it

Accepted Answer

A)  crosses the placenta. 
B)  binds an antigenic determinant. 
C)  attaches to a mast cell. 
D)  activates the kinin system. 
E)  activates complement. 
A)  crosses the placenta. 
B)  binds an antigenic determinant. 
C)  attaches to a mast cell. 
D)  activates the kinin system. 
E)  activates complement.

Question 6

Which basal lamina component binds cations and water to form gels that can withstand compression?

Accepted Answer

A)  Collagen 
B)  Entactin 
C)  Laminin 
D)  Nidogen 
E)  Perlecan 
A)  Collagen 
B)  Entactin 
C)  Laminin 
D)  Nidogen 
E)  Perlecan

Question 7

All of the following statements are true with regard to antibody molecules EXCEPT

Accepted Answer

A)  Fc combines with determinant sites on antigens. 
B)  Fc is part of the heavy chain. 
C)  Fc contains carbohydrate. 
D)  Fc determines physical/chemical characteristics of antibodies. 
E)  Fc usually reacts with complement. 
A)  Fc combines with determinant sites on antigens. 
B)  Fc is part of the heavy chain. 
C)  Fc contains carbohydrate. 
D)  Fc determines physical/chemical characteristics of antibodies. 
E)  Fc usually reacts with complement.

Question 8

How many subunits does laminin have?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 9

Which of the following immunoglobulins is present normally in plasma at the highest concentration?

Accepted Answer

A)  IgA 
B)  IgM 
C)  IgG 
D)  IgD 
E)  IgE 
A)  IgA 
B)  IgM 
C)  IgG 
D)  IgD 
E)  IgE

Question 10

The hemoglobin variant Hb Little Rock exhibits decreased binding of 2,3-bisphosphoglycerate. The most likely consequence of this mutation is

Accepted Answer

A)  altered association - dissociation of subunits. 
B)  decreased stability. 
C)  decreased oxygen affinity. 
D)  increased oxygen affinity. 
E)  increased loss of heme groups. 
A)  altered association - dissociation of subunits. 
B)  decreased stability. 
C)  decreased oxygen affinity. 
D)  increased oxygen affinity. 
E)  increased loss of heme groups.

Question 11

All of the following are correct with respect to human IgE EXCEPT

Accepted Answer

A)  the IgE heavy chain has 5 constant region domains. 
B)  IgE binds tightly to mast cell membranes. 
C)  the serum concentration of IgE is quite low when compared to the other immunoglobulins. 
D)  food-specific IgE is associated with true food allergies. 
E)  the reaction of a food antigen with mast cell membrane-bound IgE leads to the release of histamine and leukotrienes. 
A)  the IgE heavy chain has 5 constant region domains. 
B)  IgE binds tightly to mast cell membranes. 
C)  the serum concentration of IgE is quite low when compared to the other immunoglobulins. 
D)  food-specific IgE is associated with true food allergies. 
E)  the reaction of a food antigen with mast cell membrane-bound IgE leads to the release of histamine and leukotrienes.

Question 12

In considering the active site of serine-proteases, a fair generalization is that

Accepted Answer

A)  nearly all the amino acid side-chains of the protein must directly participate in catalysis. 
B)  all the amino acid residues which are involved in the active site are adjacent because they are located on the same short stretch of the polypeptide backbone. 
C)  the conformation of the active site region does not exist at all until the substrate is bound. 
D)  the amino acid residues which form the active site are in close proximity because of the specific three-dimensional conformation the protein has adopted. 
E)  only one amino acid residue is involved in the active site. 
A)  nearly all the amino acid side-chains of the protein must directly participate in catalysis. 
B)  all the amino acid residues which are involved in the active site are adjacent because they are located on the same short stretch of the polypeptide backbone. 
C)  the conformation of the active site region does not exist at all until the substrate is bound. 
D)  the amino acid residues which form the active site are in close proximity because of the specific three-dimensional conformation the protein has adopted. 
E)  only one amino acid residue is involved in the active site.

Question 13

During vigorous physical activity, the Bohr effect would enhance the delivery of oxygen to the tissues of the body. All of the following are associated with this effect at the tissues EXCEPT

Accepted Answer

A)  a conformational change occurs that alters the pKa and hence the charge on the imidazole groups of the hemoglobin molecules. 
B)  the oxygen-hemoglobin association curve shifts to the right. 
C)  the tense form of hemoglobin is stabilized. 
D)  hydrogen ions are released from the hemoglobin to the tissues. 
E)  there are alterations in the salt linkages of the hemoglobin molecules. 
A)  a conformational change occurs that alters the pKa and hence the charge on the imidazole groups of the hemoglobin molecules. 
B)  the oxygen-hemoglobin association curve shifts to the right. 
C)  the tense form of hemoglobin is stabilized. 
D)  hydrogen ions are released from the hemoglobin to the tissues. 
E)  there are alterations in the salt linkages of the hemoglobin molecules.

Question 14

Similarities among the immunoglobulin domains in the light chains of immunoglobulin G include all of the following EXCEPT

Accepted Answer

A)  a disulfide bond stabilizes the structure. 
B)  amino acid sequences are similar but not identical. 
C)  complementarity determining regions are located between beta?strands. 
D)  each domain folds independently from the others. 
E)  the secondary structure is dominated by beta?sheets. 
A)  a disulfide bond stabilizes the structure. 
B)  amino acid sequences are similar but not identical. 
C)  complementarity determining regions are located between beta?strands. 
D)  each domain folds independently from the others. 
E)  the secondary structure is dominated by beta?sheets.

Question 15

78Fetal hemoglobin has a higher affinity for O2 than adult hemoglobin. This is due to

Accepted Answer

A)  increased number of salt bridges between alpha and beta chains. 
B)  increased ability to bind to 2,3-bisphosphoglycerate (BPG). 
C)  decreased ability to bind to BPG. 
D)  decreased affinity for CO2. 
E)  increased Bohr effect. 
A)  increased number of salt bridges between alpha and beta chains. 
B)  increased ability to bind to 2,3-bisphosphoglycerate (BPG). 
C)  decreased ability to bind to BPG. 
D)  decreased affinity for CO2. 
E)  increased Bohr effect.

Exam 9: Protein II: Structure-Function Relationships in Protein Families

Which of the following participates in the reaction at the catalytic site of chymotrypsin?

Which of the following results in a shift of the oxyhemoglobin dissociation curve to the right?

Which of the following regarding 2,3-BPG is correct?

Similarities between hemoglobin and myoglobin include:

The primary function of an antibody has been fulfilled when it

Which basal lamina component binds cations and water to form gels that can withstand compression?

All of the following statements are true with regard to antibody molecules EXCEPT

How many subunits does laminin have?

Which of the following immunoglobulins is present normally in plasma at the highest concentration?

The hemoglobin variant Hb Little Rock exhibits decreased binding of 2,3-bisphosphoglycerate. The most likely consequence of this mutation is

All of the following are correct with respect to human IgE EXCEPT

In considering the active site of serine-proteases, a fair generalization is that

During vigorous physical activity, the Bohr effect would enhance the delivery of oxygen to the tissues of the body. All of the following are associated with this effect at the tissues EXCEPT

Similarities among the immunoglobulin domains in the light chains of immunoglobulin G include all of the following EXCEPT

78Fetal hemoglobin has a higher affinity for O2 than adult hemoglobin. This is due to

Eukaryotic Cell Structure

DNA and RNA: Composition and Structure

Protein I: 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

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

Filters

78Fetal hemoglobin has a higher affinity for O₂ than adult hemoglobin. This is due to