HMX Immunology Test 2 Questions with
100% Correct Answers | Latest Version
2024 | Verified
T-cell receptors, when coexpressed with CDS mole cules, are restricted to recognizing and binding
peptide fragments associated with
A. CD3 molecules.
B. CD4 molecules.
C. MHC class I molecules.
D. MHC class II molecules.
E. MHC class Ill molecules. - ✔✔The correct answer is C. cos+ T cells are re stricted to the recognition of
pMHC I complexes. C03 molecules are associated with the TCR
on the T-cell surface and are found on both mature C04+ and cos+ T cells. C04+ T cells are restricted to
the recognition of pMHC class II complexes. MHC class Ill molecules include complement components
C4, Bf, and C2 and are not involved in T-cell recognition.
B lymphocytes synthesize and express immunoglobulin
A. containing multiple epitope specificities.
B. in cytoplasmic phagosomes.
C. in membrane complexes also containing CD3.
D. on their cell membrane surface.
E. only after leaving the bone marrow. - ✔✔The correct answer is D. B cells synthesize and express
immunoglobulin on their cell surfaces. Immunoglobulins within an individual B cell contain specificity for
one epitope,
not several. Cytoplasmic phagosomes are involved in degradation of unwanted materials. Membrane
complexes also containing C03 are T-cell receptors (TCR) on the surfaces of T cells. B cells express surface
lgM before leaving the bone marrow.
The primary lymphoid organs are those in which
A. adaptive immune responses are usually initiated.
B. filtration devices remove foreign matter.
,C. large numbers of circulating leukocytes make contact with one another.
D. lymphocytes undergo their initial differentiation.
E. pattern recognition receptors bind antigens. - ✔✔The correct answer is D. Primary lymphoid or gans
are sites where lymphocytes undergo their initial differentiation. Adaptive immune respons es are
initiated by mature lymphocytes that have migrated out of primary lymphoid organs. Secondary
lymphoid organs contain filtration devices to remove foreign materials. Circulating leukocytes are found
within blood and lymph and secondary lymphoid organs but not within primary lymphoid organs.
Pattern recognition receptors (PRRs) are expressed by cells of the innate immune system (see Chapter 5).
The thymus is the site of initial differentiation for
A. B cells.
B. erythrocytes.
C. hematopoietic stem cells.
D. NK cells.
E. T cells. - ✔✔The correct answer is E. The thymus is the site of initial differentiation of T cells. Eryth
rocytes develop from erythroid precursors in the bone marrow. Hematopoietic stem cells differentiate
along any one of several lineages within the bone marrow. Natural killer (NK) cells develop within the
bone marrow and lack rear ranged TCR.
Lymph nodes have two main regions: the
A. cortex and medulla.
B. lymph and cortex.
C. reticulum and cortex.
D. lymphandmedulla.
E. reticulum and medulla - ✔✔The correct answer is A. Lymph nodes are di vided into the cortex and the
medulla. Lymph is the watery fluid of the lymphatic circulatory sys tem that contains leukocytes and
cellular debris from various organs and tissues. Reticulum referstotheframeworkofalymphnodethatis
composed of phagocytes and specialized kinds of reticular or dendritic cells.
Which of the following molecules is expressed on the
surface of mature CD4+ cells?
A. B-cell receptor
, B. CD1d
C. CD3
D. CDS
E. CD19 - ✔✔The correct answer is C. Mature T cells (both CD4+ and CDS+) express CD3, a molecular
complex associated with the TCR. CD4+ cells are T cells with T helper function and do not express B-cell
receptors. CD1 d is a specialized, nonclassical MHC class I molecule on NKT cells. CDS is a molecule
expressed by T cyto toxic and suppressor cells. CD1 9 is expressed on B cells.
Positive selection refers to
A. the ability of single positive cells to bind both MHC class I and II.
B. cortical thymocytes' acquisition of TCR.
C. migration of stem cells to the thymus to become T cells.
D. programmed cell death of single positive T cells.
E. recognition of MHC by CD4+cDs+ thymocytes. - ✔✔The correct answer is E. Positive selection refers to
recognition of MHC class I (by CDS) or MHC class II (by CD4) by double-positive (CD4+cos+) thymocytes.
Single positive thymocytes (and T cells) are either CD4+ or cos+ and recognize either MHC class II (CD4)
or MHC class I (CDS), but not both. Cortical thymocytes acquire a nascent TCR as well as CD4 and CDS
surface molecules, resulting
in formation of double-positive (CD4+cos+) thymocytes. Precursor T cells migrate or traffic from the
bone marrow to the thymus before acquiring CD4 and CDS, which they will do as cortical thymocytes.
Cells that fail to complete positive selection undergo programmed cell death (apoptosis).
Which of the following is a primary lymphoid organ?
A. Bone marrow
B. Lymph node
C. Peyer's patch
D. Spleen
E. Tonsil - ✔✔The correct answer is D. The white pulp of the spleen is enriched in plasma cells secret ing
immunoglobulin, in addition to B and T lymphocytes. Erythrocytes are found within the red pulp of the
spleen. CD4+cos+ T cells are found in the thymus. Natural killer cells function within peripheral blood.
Precursors of B cells are located in the bone marrow.
T cells recognize epitopes they have never before encountered by
100% Correct Answers | Latest Version
2024 | Verified
T-cell receptors, when coexpressed with CDS mole cules, are restricted to recognizing and binding
peptide fragments associated with
A. CD3 molecules.
B. CD4 molecules.
C. MHC class I molecules.
D. MHC class II molecules.
E. MHC class Ill molecules. - ✔✔The correct answer is C. cos+ T cells are re stricted to the recognition of
pMHC I complexes. C03 molecules are associated with the TCR
on the T-cell surface and are found on both mature C04+ and cos+ T cells. C04+ T cells are restricted to
the recognition of pMHC class II complexes. MHC class Ill molecules include complement components
C4, Bf, and C2 and are not involved in T-cell recognition.
B lymphocytes synthesize and express immunoglobulin
A. containing multiple epitope specificities.
B. in cytoplasmic phagosomes.
C. in membrane complexes also containing CD3.
D. on their cell membrane surface.
E. only after leaving the bone marrow. - ✔✔The correct answer is D. B cells synthesize and express
immunoglobulin on their cell surfaces. Immunoglobulins within an individual B cell contain specificity for
one epitope,
not several. Cytoplasmic phagosomes are involved in degradation of unwanted materials. Membrane
complexes also containing C03 are T-cell receptors (TCR) on the surfaces of T cells. B cells express surface
lgM before leaving the bone marrow.
The primary lymphoid organs are those in which
A. adaptive immune responses are usually initiated.
B. filtration devices remove foreign matter.
,C. large numbers of circulating leukocytes make contact with one another.
D. lymphocytes undergo their initial differentiation.
E. pattern recognition receptors bind antigens. - ✔✔The correct answer is D. Primary lymphoid or gans
are sites where lymphocytes undergo their initial differentiation. Adaptive immune respons es are
initiated by mature lymphocytes that have migrated out of primary lymphoid organs. Secondary
lymphoid organs contain filtration devices to remove foreign materials. Circulating leukocytes are found
within blood and lymph and secondary lymphoid organs but not within primary lymphoid organs.
Pattern recognition receptors (PRRs) are expressed by cells of the innate immune system (see Chapter 5).
The thymus is the site of initial differentiation for
A. B cells.
B. erythrocytes.
C. hematopoietic stem cells.
D. NK cells.
E. T cells. - ✔✔The correct answer is E. The thymus is the site of initial differentiation of T cells. Eryth
rocytes develop from erythroid precursors in the bone marrow. Hematopoietic stem cells differentiate
along any one of several lineages within the bone marrow. Natural killer (NK) cells develop within the
bone marrow and lack rear ranged TCR.
Lymph nodes have two main regions: the
A. cortex and medulla.
B. lymph and cortex.
C. reticulum and cortex.
D. lymphandmedulla.
E. reticulum and medulla - ✔✔The correct answer is A. Lymph nodes are di vided into the cortex and the
medulla. Lymph is the watery fluid of the lymphatic circulatory sys tem that contains leukocytes and
cellular debris from various organs and tissues. Reticulum referstotheframeworkofalymphnodethatis
composed of phagocytes and specialized kinds of reticular or dendritic cells.
Which of the following molecules is expressed on the
surface of mature CD4+ cells?
A. B-cell receptor
, B. CD1d
C. CD3
D. CDS
E. CD19 - ✔✔The correct answer is C. Mature T cells (both CD4+ and CDS+) express CD3, a molecular
complex associated with the TCR. CD4+ cells are T cells with T helper function and do not express B-cell
receptors. CD1 d is a specialized, nonclassical MHC class I molecule on NKT cells. CDS is a molecule
expressed by T cyto toxic and suppressor cells. CD1 9 is expressed on B cells.
Positive selection refers to
A. the ability of single positive cells to bind both MHC class I and II.
B. cortical thymocytes' acquisition of TCR.
C. migration of stem cells to the thymus to become T cells.
D. programmed cell death of single positive T cells.
E. recognition of MHC by CD4+cDs+ thymocytes. - ✔✔The correct answer is E. Positive selection refers to
recognition of MHC class I (by CDS) or MHC class II (by CD4) by double-positive (CD4+cos+) thymocytes.
Single positive thymocytes (and T cells) are either CD4+ or cos+ and recognize either MHC class II (CD4)
or MHC class I (CDS), but not both. Cortical thymocytes acquire a nascent TCR as well as CD4 and CDS
surface molecules, resulting
in formation of double-positive (CD4+cos+) thymocytes. Precursor T cells migrate or traffic from the
bone marrow to the thymus before acquiring CD4 and CDS, which they will do as cortical thymocytes.
Cells that fail to complete positive selection undergo programmed cell death (apoptosis).
Which of the following is a primary lymphoid organ?
A. Bone marrow
B. Lymph node
C. Peyer's patch
D. Spleen
E. Tonsil - ✔✔The correct answer is D. The white pulp of the spleen is enriched in plasma cells secret ing
immunoglobulin, in addition to B and T lymphocytes. Erythrocytes are found within the red pulp of the
spleen. CD4+cos+ T cells are found in the thymus. Natural killer cells function within peripheral blood.
Precursors of B cells are located in the bone marrow.
T cells recognize epitopes they have never before encountered by
