Question 1

Unlike B cells,T cells do not engage in any of the following processes except

Accepted Answer

A) alternative splicing to produce a secreted form of the T-cell receptor 
B) alternative splicing to produce different isoforms of the T-cell receptor 
C) isotype switching 
D) somatic hypermutation 
E) somatic recombination 
A) alternative splicing to produce a secreted form of the T-cell receptor 
B) alternative splicing to produce different isoforms of the T-cell receptor 
C) isotype switching 
D) somatic hypermutation 
E) somatic recombination E

Question 2

Which of the following is not a characteristic of native antigen recognized by T cells?

Accepted Answer

A) peptides ranging between 8 and 25 amino acids in length 
B) not requiring degradation for recognition 
C) amino acid sequences not found in host proteins 
D) primary,and not secondary,structure of protein 
E) binding to major histocompatibility complex molecules on the surface of antigen-presenting cells. 
A) peptides ranging between 8 and 25 amino acids in length 
B) not requiring degradation for recognition 
C) amino acid sequences not found in host proteins 
D) primary,and not secondary,structure of protein 
E) binding to major histocompatibility complex molecules on the surface of antigen-presenting cells. B

Question 3

Directional selection is best described as

Accepted Answer

A) all polymorphic alleles preserved in a population 
B) T-cell receptor interaction with peptide:MHC complexes directed to a planar interface 
C) a mechanism in T cells that is analogous to affinity maturation of immunoglobulins 
D) selected alleles increase in frequency in a population 
E) selection of most appropriate transplant donor directed at the identification of identical or similar combinations of HLA alleles compared with the transplant recipient. 
A) all polymorphic alleles preserved in a population 
B) T-cell receptor interaction with peptide:MHC complexes directed to a planar interface 
C) a mechanism in T cells that is analogous to affinity maturation of immunoglobulins 
D) selected alleles increase in frequency in a population 
E) selection of most appropriate transplant donor directed at the identification of identical or similar combinations of HLA alleles compared with the transplant recipient. D

Question 4

The immunological consequence of severe combined immunodeficiency disease (SCID)caused by a genetic defect in either RAG-1 or RAG-2 genes is

Accepted Answer

A) lack of somatic recombination in T-cell receptor and immunoglobulin gene loci 
B) lack of somatic recombination in T-cell receptor loci 
C) lack of somatic recombination in immunoglobulin loci 
D) lack of somatic hypermutation in T-cell receptor and immunoglobulin loci 
E) lack of somatic hypermutation in T-cell receptor loci. 
A) lack of somatic recombination in T-cell receptor and immunoglobulin gene loci 
B) lack of somatic recombination in T-cell receptor loci 
C) lack of somatic recombination in immunoglobulin loci 
D) lack of somatic hypermutation in T-cell receptor and immunoglobulin loci 
E) lack of somatic hypermutation in T-cell receptor loci.

Question 5

The antigen-recognition site of T-cell receptors is formed by the association of which of the following domains?

Accepted Answer

A) Vα and Cα 
B) Vβ and Cβ 
C) Cα and Cβ 
D) Vα and Cβ 
E) Vα and Vβ. 
A) Vα and Cα 
B) Vβ and Cβ 
C) Cα and Cβ 
D) Vα and Cβ 
E) Vα and Vβ.

Question 6

Which of the following describes the sequence of events involved in the processing of peptides that will be presented as antigen with MHC class II?

Accepted Answer

A) protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II →endocytosis →plasma membrane 
B) endocytosis →protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II →plasma membrane 
C) removal of CLIP from MHC class II →binding of peptide to MHC class II →protease activity →endocytosis →plasma membrane 
D) binding of peptide to MHC class II →endocytosis →removal of CLIP from MHC class II →protease activity →plasma membrane 
E) plasma membrane →endocytosis →protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II. 
A) protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II →endocytosis →plasma membrane 
B) endocytosis →protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II →plasma membrane 
C) removal of CLIP from MHC class II →binding of peptide to MHC class II →protease activity →endocytosis →plasma membrane 
D) binding of peptide to MHC class II →endocytosis →removal of CLIP from MHC class II →protease activity →plasma membrane 
E) plasma membrane →endocytosis →protease activity →removal of CLIP from MHC class II →binding of peptide to MHC class II.

Question 7

The combination of all HLA class I and class II allotypes that an individual expresses is referred to as their

Accepted Answer

A) haplotype 
B) allotype 
C) isotype 
D) autotype 
E) HLA type. 
A) haplotype 
B) allotype 
C) isotype 
D) autotype 
E) HLA type.

Question 8

5–27	Pathogens that infect the human body replicate either inside cells (such as viruses) or extracellularly, in the blood or in the extracellular spaces in tissues.
A.	Identify (i) the class of T cells that are stimulated by intracellular pathogens, (ii) their co-receptor, (iii) the MHC molecule used for recognition of antigen and (iv) the T-cell effector function.
B.	Repeat this for the classes of T cells that are stimulated by extracellular pathogens. For the purposes of this question, count those pathogens (such as mycobacteria) that can survive and live inside intracellular vesicles after being taken up by macrophages as extracellular pathogens.

Accepted Answer

A. (i)Pathogens that are propagating fre

Question 9

Which of the following describes a ligand for an α:β T-cell receptor?

Accepted Answer

A) carbohydrate:MHC complex 
B) lipid:MHC complex 
C) peptide:MHC complex 
D) all of the above 
E) none of the above. 
A) carbohydrate:MHC complex 
B) lipid:MHC complex 
C) peptide:MHC complex 
D) all of the above 
E) none of the above.

Question 10

Explain the importance of promiscuous binding specificity exhibited by MHC class I and class II molecules.

Accepted Answer

Each MHC molecule can bind to a very lar

Question 11

T-cell receptors structurally resemble

Accepted Answer

A) the Fc portion of immunoglobulins 
B) MHC class I molecules 
C) secreted antibodies 
D) a single Fab of immunoglobulins 
E) CD3 ε chains. 
A) the Fc portion of immunoglobulins 
B) MHC class I molecules 
C) secreted antibodies 
D) a single Fab of immunoglobulins 
E) CD3 ε chains.

Question 12

Which is the most likely reason that HIV-infected people with heterozygous HLA loci have a delayed progression to AIDS compared with patients who are homozygous at one or more HLA loci?

Accepted Answer

A) The greater number of HLA alleles provides a wider variety of HLA molecules for presenting HIV-derived peptides to CD8 T cells even if HIV mutates during the course of infection. 
B) Heterozygotes have more opportunity for interallelic conversion and can therefore express larger numbers of MHC alleles. 
C) Directional selection mechanisms favor heterozygotes and provide selective advantage to pathogen exposure. 
D) As heterozygosity increases,so does the concentration of alloantibodies in the serum,some of which cross-react with and neutralize HIV. 
A) The greater number of HLA alleles provides a wider variety of HLA molecules for presenting HIV-derived peptides to CD8 T cells even if HIV mutates during the course of infection. 
B) Heterozygotes have more opportunity for interallelic conversion and can therefore express larger numbers of MHC alleles. 
C) Directional selection mechanisms favor heterozygotes and provide selective advantage to pathogen exposure. 
D) As heterozygosity increases,so does the concentration of alloantibodies in the serum,some of which cross-react with and neutralize HIV.

Question 13

All of the following are highly polymorphic except

Accepted Answer

A) HLA-A α chain 
B) HLA-DO α chain 
C) HLA-B α chain 
D) HLA-DR β chain 
E) HLA-C α chain. 
A) HLA-A α chain 
B) HLA-DO α chain 
C) HLA-B α chain 
D) HLA-DR β chain 
E) HLA-C α chain.

Question 14

Owing to the location of the δ-chain locus of the T-cell receptor on chromosome 14,if the _______-chain locus rearranges by somatic recombination,then the δ-chain locus is _______:

Accepted Answer

A) α; also rearranged 
B) α; deleted 
C) α; transcribed 
D) β; deleted 
E) γ; also rearranged. 
A) α; also rearranged 
B) α; deleted 
C) α; transcribed 
D) β; deleted 
E) γ; also rearranged.

Question 15

In contrast to immunoglobulins,α:β T-cell receptors recognize epitopes present on _______ antigens:

Accepted Answer

A) carbohydrate 
B) lipid 
C) protein 
D) carbohydrate and lipid 
E) carbohydrate,lipid,and protein. 
A) carbohydrate 
B) lipid 
C) protein 
D) carbohydrate and lipid 
E) carbohydrate,lipid,and protein.

Question 16

The role of the CD3 proteins and ζ chain on the surface of the cell is to

Accepted Answer

A) transduce signals to the interior of the T cell 
B) bind to antigen associated with MHC molecules 
C) bind to MHC molecules 
D) bind to CD4 or CD8 molecules 
E) facilitate antigen processing of antigens that bind to the surface of T cells. 
A) transduce signals to the interior of the T cell 
B) bind to antigen associated with MHC molecules 
C) bind to MHC molecules 
D) bind to CD4 or CD8 molecules 
E) facilitate antigen processing of antigens that bind to the surface of T cells.

Question 17

Which of the following cell types is not considered a professional antigen-presenting cell?

Accepted Answer

A) macrophage 
B) neutrophil 
C) B cell 
D) dendritic cell 
E) all of the above are professional antigen-presenting cells. 
A) macrophage 
B) neutrophil 
C) B cell 
D) dendritic cell 
E) all of the above are professional antigen-presenting cells.

Question 18

Which of the following characteristics is common to both T-cell receptors and immunoglobulins?

Accepted Answer

A) Somatic recombination of V,D,and J segments is responsible for the diversity of antigen-binding sites. 
B) Somatic hypermutation changes the affinity of antigen-binding sites and contributes to further diversification. 
C) Class switching enables a change in effector function. 
D) The antigen receptor is composed of two identical heavy chains and two identical light chains. 
E) Carbohydrate,lipid,and protein antigens are recognized and stimulate a response. 
A) Somatic recombination of V,D,and J segments is responsible for the diversity of antigen-binding sites. 
B) Somatic hypermutation changes the affinity of antigen-binding sites and contributes to further diversification. 
C) Class switching enables a change in effector function. 
D) The antigen receptor is composed of two identical heavy chains and two identical light chains. 
E) Carbohydrate,lipid,and protein antigens are recognized and stimulate a response.

Question 19

Compare the organization of T-cell receptor α and β genes (the TCRα and TCRβ loci)with the organization of immunoglobulin heavy-chain and light-chain genes.

Accepted Answer

The organization of the TCRα locus resem

Question 20

Which of the following accurately completes this statement: "The function of _______ T cells is to make contact with _______ and _______"? (Select all that apply.)

Accepted Answer

A) CD8; virus-infected cells; kill virus-infected cells 
B) CD8; B cells; stimulate B cells to differentiate into plasma cells 
C) CD4; macrophages; enhance microbicidal powers of macrophages 
D) CD4; B cells; stimulate B cells to differentiate into plasma cells 
E) All of the above are accurate. 
A) CD8; virus-infected cells; kill virus-infected cells 
B) CD8; B cells; stimulate B cells to differentiate into plasma cells 
C) CD4; macrophages; enhance microbicidal powers of macrophages 
D) CD4; B cells; stimulate B cells to differentiate into plasma cells 
E) All of the above are accurate.

Unlike B cells,T cells do not engage in any of the following processes except

Which of the following is not a characteristic of native antigen recognized by T cells?

Directional selection is best described as

The immunological consequence of severe combined immunodeficiency disease (SCID)caused by a genetic defect in either RAG-1 or RAG-2 genes is

The antigen-recognition site of T-cell receptors is formed by the association of which of the following domains?

Which of the following describes the sequence of events involved in the processing of peptides that will be presented as antigen with MHC class II?

The combination of all HLA class I and class II allotypes that an individual expresses is referred to as their

Which of the following describes a ligand for an α:β T-cell receptor?

Explain the importance of promiscuous binding specificity exhibited by MHC class I and class II molecules.

T-cell receptors structurally resemble

Which is the most likely reason that HIV-infected people with heterozygous HLA loci have a delayed progression to AIDS compared with patients who are homozygous at one or more HLA loci?

All of the following are highly polymorphic except

Owing to the location of the δ-chain locus of the T-cell receptor on chromosome 14,if the _-chain locus rearranges by somatic recombination,then the δ-chain locus is _:

In contrast to immunoglobulins,α:β T-cell receptors recognize epitopes present on _______ antigens:

The role of the CD3 proteins and ζ chain on the surface of the cell is to

Which of the following cell types is not considered a professional antigen-presenting cell?

Which of the following characteristics is common to both T-cell receptors and immunoglobulins?

Compare the organization of T-cell receptor α and β genes (the TCRα and TCRβ loci)with the organization of immunoglobulin heavy-chain and light-chain genes.

Which of the following accurately completes this statement: "The function of ___ T cells is to make contact with _ and _____"? (Select all that apply.)

Elements of the Immune System and Their Roles in Defense

Innate Immunity: the Immediate Response to Infection

Innate Immunity: the Induced Response to Infection

Antibody Structure and the Generation of B-Cell Diversity

The Development of B Lymphocytes

The Development of T Lymphocytes

T Cell-Mediated Immunity

Immunity Mediated by B Cells and Antibodies

Preventing Infection at Mucosal Surfaces

Immunological Memory and Vaccination

Coevolution of Innate and Adaptive Immunity

Failures of the Bodys Defenses

Ige-Mediated Immunity and Allergy

Transplantation of Tissues and Organs

Disruption of Healthy Tissue by the Adaptive Immune Response

Cancer and Its Interactions With the Immune System

Filters

Exam 5: Antigen Recognition by T Lymphocytes

Unlike B cells,T cells do not engage in any of the following processes except

Which of the following is not a characteristic of native antigen recognized by T cells?

Directional selection is best described as

The immunological consequence of severe combined immunodeficiency disease (SCID)caused by a genetic defect in either RAG-1 or RAG-2 genes is

The antigen-recognition site of T-cell receptors is formed by the association of which of the following domains?

Which of the following describes the sequence of events involved in the processing of peptides that will be presented as antigen with MHC class II?

The combination of all HLA class I and class II allotypes that an individual expresses is referred to as their

Which of the following describes a ligand for an α:β T-cell receptor?

Explain the importance of promiscuous binding specificity exhibited by MHC class I and class II molecules.

T-cell receptors structurally resemble

Which is the most likely reason that HIV-infected people with heterozygous HLA loci have a delayed progression to AIDS compared with patients who are homozygous at one or more HLA loci?

All of the following are highly polymorphic except

Owing to the location of the δ-chain locus of the T-cell receptor on chromosome 14,if the _______-chain locus rearranges by somatic recombination,then the δ-chain locus is _______:

In contrast to immunoglobulins,α:β T-cell receptors recognize epitopes present on _______ antigens:

The role of the CD3 proteins and ζ chain on the surface of the cell is to

Which of the following cell types is not considered a professional antigen-presenting cell?

Which of the following characteristics is common to both T-cell receptors and immunoglobulins?

Compare the organization of T-cell receptor α and β genes (the TCRα and TCRβ loci)with the organization of immunoglobulin heavy-chain and light-chain genes.

Which of the following accurately completes this statement: "The function of _______ T cells is to make contact with _______ and _______"? (Select all that apply.)

Elements of the Immune System and Their Roles in Defense

Innate Immunity: the Immediate Response to Infection

Innate Immunity: the Induced Response to Infection

Antibody Structure and the Generation of B-Cell Diversity

The Development of B Lymphocytes

The Development of T Lymphocytes

T Cell-Mediated Immunity

Immunity Mediated by B Cells and Antibodies

Preventing Infection at Mucosal Surfaces

Immunological Memory and Vaccination

Coevolution of Innate and Adaptive Immunity

Failures of the Bodys Defenses

Ige-Mediated Immunity and Allergy

Transplantation of Tissues and Organs

Disruption of Healthy Tissue by the Adaptive Immune Response

Cancer and Its Interactions With the Immune System

Filters

Owing to the location of the δ-chain locus of the T-cell receptor on chromosome 14,if the _-chain locus rearranges by somatic recombination,then the δ-chain locus is _:

Which of the following accurately completes this statement: "The function of ___ T cells is to make contact with _ and _____"? (Select all that apply.)