Immunology & Serology Questions
with 100% Correct Answers
*From the following, identify a specific component of the adaptive immune
system that is formed in response to antigenic stimulation:
A. Lysozyme
B. Complement
C. Commensal organisms
D. Immunoglobulin Correct Answer: *D. Immunoglobulin is a specific part of the
adaptive immune system and is formed only in response to a specific antigenic
stimulation. Complement, lysozyme, and commensal organisms all act
nonspecifically as a part of the adaptive immune system. These three
components do not require any type of specific antigenic stimulation.
*Which two organs are considered the primary lymphoid organs in which
immunocompetent cells originate and mature?
A. Thyroid and Peyer's patches B. Thymus and bone marrow
C. Spleen and mucosal-associated lymphoid tissue (MALT)
D. Lymph nodes and thoracic duct Correct Answer: *B. The bone marrow and
thymus are considered primary lymphoid organs because immunocompetent
cells either originate or mature in them. Some immunocompetent cells mature
or reside in the bone marrow (the source of all hematopoietic cells) until
transported to the thymus, spleen, or Peyer's patches, where they process
antigen or manufacture antibody. T lymphocytes, after originating in the bone
marrow, travel to the thymus to mature and differentiate.
,*What type of B cells are formed after antigen stimulation?
A. Plasma cells and memory B cells
B. Mature B cells
C. Antigen-dependent B cells
*A Mature B cells exhibit surface immunoglobulin that may cross link a foreign
antigen, thus forming the activated B cell and leading to capping and
internalization of antigen. The activated B cell gives rise to plasma cells that
produce and secrete immunoglobulins and memory cells that reside in
lymphoid organs.D. Receptor-activated B cells Correct Answer: *A. Mature B
cells exhibit surface immunoglobulin that may cross link a foreign antigen, thus
forming the activated B cell and leading to capping and internalization of
antigen. The activated B cell gives rise to plasma cells that produce and secrete
immunoglobulins and memory cells that reside in lymphoid organs.
*T cells travel from the bone marrow to the thymus for maturation. What is the
correct order of the maturation sequence for T cells in the thymus?
A. Bone marrow to the cortex; after thymic education, released back to
peripheral circulation
B. Maturation and selection occur in the cortex; migration to the medulla;
release of mature T cells to secondary lymphoid organs
C. Storage in either the cortex or medulla; release of T cells into the peripheral
circulation
D. Activation and selection occur in the medulla; mature T cells are stored in the
cortex until activated by antigen Correct Answer: *B. Immature T cells travel
from the bone marrow to the thymus to mature into functional T cells. Once in
,the thymus, T cells undergo a selection and maturation sequence that begins in
the cortex and moves to the medulla of the thymus. Thymic factors such as
thymosin and thymopoietin and cells within the thymus such as macrophages
and dendritic cells assist in this sequence. After completion of the maturation
cycle, T cells are released to secondary lymphoid organs to await antigen
recognition and activation.
*Which cluster of differentiation (CD) marker appears during the first stage of T-
cell development and remains present as an identifying marker for T cells?
A. CD1
B. CD2
C. CD3
D. CD4 or CD8 Correct Answer: *B. The CD2 marker appears during the first
stage of T-cell development and can be used to differentiate T cells from other
lymphocytes. This T-lymphocyte receptor binds sheep red blood cells (RBCs). This
peculiar characteristic was the basis for the classic E rosette test once used to
enumerate T cells in peripheral blood. CD2 is not specific for T cells, however,
and is also found on large granular lymphocytes (LGL or natural killer [NK] cells).
*Which markers are found on mature, peripheral helper T cells? A. CD1, CD2,
CD4
B. CD2, CD3, CD8
C. CD1, CD3, CD4
D. CD2, CD3, CD4 Correct Answer: *D. Mature, peripheral helper T cells have the
CD2 (E rosette), CD3 (mature T cell), and CD4 (helper) markers.
, *Which T cell expresses the CD8 marker and acts specifically to kill tumors or
virally infected cells?
A. Helper T
B. T suppressor
C. T cytotoxic
D. T inducer/suppressor Correct Answer: *C. T cytotoxic cells recognize antigen
in association with major histocompatibility complex (MHC) class I complexes
and act against target cells that express foreign antigens. These include viral
antigens and the human leukocyte antigens (HLA) that are the target of graft
rejection
*How are cytotoxic T cells (TC cells) and natural killer (NK) cells similar?
A. Require antibody to be present B. Effective against virally infected cells
C. Recognize antigen in association with HLA class II markers
D. Do not bind to infected cells Correct Answer: *B. Both TC and NK cells are
effective against virally infected cells, and neither requires antibody to be
present to bind to infected cells. NK cells do not exhibit MHC class restriction,
whereas activation of TC cells requires the presence of MHC class I molecules in
association with the viral antigen.
*What is the name of the process by which phagocytic cells are attracted to a
substance such as a bacterial peptide?
A. Diapedesis
B. Degranulation
with 100% Correct Answers
*From the following, identify a specific component of the adaptive immune
system that is formed in response to antigenic stimulation:
A. Lysozyme
B. Complement
C. Commensal organisms
D. Immunoglobulin Correct Answer: *D. Immunoglobulin is a specific part of the
adaptive immune system and is formed only in response to a specific antigenic
stimulation. Complement, lysozyme, and commensal organisms all act
nonspecifically as a part of the adaptive immune system. These three
components do not require any type of specific antigenic stimulation.
*Which two organs are considered the primary lymphoid organs in which
immunocompetent cells originate and mature?
A. Thyroid and Peyer's patches B. Thymus and bone marrow
C. Spleen and mucosal-associated lymphoid tissue (MALT)
D. Lymph nodes and thoracic duct Correct Answer: *B. The bone marrow and
thymus are considered primary lymphoid organs because immunocompetent
cells either originate or mature in them. Some immunocompetent cells mature
or reside in the bone marrow (the source of all hematopoietic cells) until
transported to the thymus, spleen, or Peyer's patches, where they process
antigen or manufacture antibody. T lymphocytes, after originating in the bone
marrow, travel to the thymus to mature and differentiate.
,*What type of B cells are formed after antigen stimulation?
A. Plasma cells and memory B cells
B. Mature B cells
C. Antigen-dependent B cells
*A Mature B cells exhibit surface immunoglobulin that may cross link a foreign
antigen, thus forming the activated B cell and leading to capping and
internalization of antigen. The activated B cell gives rise to plasma cells that
produce and secrete immunoglobulins and memory cells that reside in
lymphoid organs.D. Receptor-activated B cells Correct Answer: *A. Mature B
cells exhibit surface immunoglobulin that may cross link a foreign antigen, thus
forming the activated B cell and leading to capping and internalization of
antigen. The activated B cell gives rise to plasma cells that produce and secrete
immunoglobulins and memory cells that reside in lymphoid organs.
*T cells travel from the bone marrow to the thymus for maturation. What is the
correct order of the maturation sequence for T cells in the thymus?
A. Bone marrow to the cortex; after thymic education, released back to
peripheral circulation
B. Maturation and selection occur in the cortex; migration to the medulla;
release of mature T cells to secondary lymphoid organs
C. Storage in either the cortex or medulla; release of T cells into the peripheral
circulation
D. Activation and selection occur in the medulla; mature T cells are stored in the
cortex until activated by antigen Correct Answer: *B. Immature T cells travel
from the bone marrow to the thymus to mature into functional T cells. Once in
,the thymus, T cells undergo a selection and maturation sequence that begins in
the cortex and moves to the medulla of the thymus. Thymic factors such as
thymosin and thymopoietin and cells within the thymus such as macrophages
and dendritic cells assist in this sequence. After completion of the maturation
cycle, T cells are released to secondary lymphoid organs to await antigen
recognition and activation.
*Which cluster of differentiation (CD) marker appears during the first stage of T-
cell development and remains present as an identifying marker for T cells?
A. CD1
B. CD2
C. CD3
D. CD4 or CD8 Correct Answer: *B. The CD2 marker appears during the first
stage of T-cell development and can be used to differentiate T cells from other
lymphocytes. This T-lymphocyte receptor binds sheep red blood cells (RBCs). This
peculiar characteristic was the basis for the classic E rosette test once used to
enumerate T cells in peripheral blood. CD2 is not specific for T cells, however,
and is also found on large granular lymphocytes (LGL or natural killer [NK] cells).
*Which markers are found on mature, peripheral helper T cells? A. CD1, CD2,
CD4
B. CD2, CD3, CD8
C. CD1, CD3, CD4
D. CD2, CD3, CD4 Correct Answer: *D. Mature, peripheral helper T cells have the
CD2 (E rosette), CD3 (mature T cell), and CD4 (helper) markers.
, *Which T cell expresses the CD8 marker and acts specifically to kill tumors or
virally infected cells?
A. Helper T
B. T suppressor
C. T cytotoxic
D. T inducer/suppressor Correct Answer: *C. T cytotoxic cells recognize antigen
in association with major histocompatibility complex (MHC) class I complexes
and act against target cells that express foreign antigens. These include viral
antigens and the human leukocyte antigens (HLA) that are the target of graft
rejection
*How are cytotoxic T cells (TC cells) and natural killer (NK) cells similar?
A. Require antibody to be present B. Effective against virally infected cells
C. Recognize antigen in association with HLA class II markers
D. Do not bind to infected cells Correct Answer: *B. Both TC and NK cells are
effective against virally infected cells, and neither requires antibody to be
present to bind to infected cells. NK cells do not exhibit MHC class restriction,
whereas activation of TC cells requires the presence of MHC class I molecules in
association with the viral antigen.
*What is the name of the process by which phagocytic cells are attracted to a
substance such as a bacterial peptide?
A. Diapedesis
B. Degranulation