©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
Unit 3 Study Guide: Chapter 12 Exam
Questions With Verified Answers
Name the branches of adaptive immunity and compare adaptive to innate immunity. -
Answers✔Adaptive immunity includes cellular (T-cell-mediated immunity) and humoral (B-cell
antibody-mediated with some T-cell-mediation) responses. The goal of both branches is the
same: eliminate an antigen and remember it so that next time adaptive responses are faster.
Cellular and humoral responses both progress through four main stages: antigen presentation,
lymphocyte activation, lymphocyte proliferation and differentiation, and antigen elimination and
memory.
Adaptive immunity differs from innate responses because they take longer to mount (few days to
more than a week between detection and response in primary exposure), are specific to a
particular antigen, and exhibit memory (secondary exposure to same antigen is rapid and
effective, frequently will not experience disease symptoms while bodies eliminate pathogen).
Adaptive responses go into action when innate first- and second-line defenses fail to contain a
threat.
Compare and contrast T and B cells. - Answers✔T-cells:
-lymphocytes that are initially produced in bone marrow and mature in thymus
-mature T cells are present at relatively low levels in circulation; reside in lymphatic tissues
-each individual cell has thousands of receptors that can only recognize one epitope
-part of cellular immune response, help coordinate humoral response
-require antigen presenting cells (APCs) to show antigen
-recognize antigens due to gene shuffling mechanisms that randomly give rise to receptors
-undergo screening to select for immune cells with self-tolerance (inability to recognize MHCs
and potential self-reaction leads to apoptosis)
-chemical signals cause clonal expansion and differentiation into effector and memory cells; T
cells can become T cytotoxic cells or T helper cells
-have single-pronged T-cell receptors (TCRs)
1
, ©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
-have MHC I proteins present on cell surface
-not considered antigen presenting cells
B-cells:
-lymphocytes that are produced and mature in bone marrow
-mature B cells are present at relatively low levels in circulation; reside in lymphatic tissues
-each individual cell has thousands of receptors that can only recognize on epitope; antibodies
released can only recognize one epitope
-part of humoral immune response only
-B cells do not require APCs to show them antigens; instead they can directly interact with an
antigen
-recognize antigens due to gene shuffling mechanisms that randomly give rise to receptors
-undergo screening to select for immune cells with self-tolerance (ability to make antibodies
against self-antigens leads to apoptosis)
-chemical signals cause clonal expansion and differentiation into effector and memory cells;
effector B cells are called plasma cells and they make antibodies—secreted form of B cell
receptor that binds to antigen that stimulated the activation event
-have MHC I and II protein
Compare and contrast T helper versus T cytotoxic cells and discuss the various T helper cell
subclasses. - Answers✔We can tell T cell lineages apart by presence of cluster of differentiation
(CD) proteins.
T cytotoxic cells (Tc cells) directly destroy infected or cancerous cells and transplant tissues. TC
cells are only in cell-mediated immunity. TC cells have CD8 proteins. TC cells interact with
MHC I presenting intracellular antigens. Only TC cells that have been trained by APCs to
recognize the given antigen can effectively patrol the body and eliminate cells displaying
suspicious antigens. To train TC cells, APCs obtain viral antigen samples by being infected with
the virus or by phagocytizing an infected host cell; if the APC is directly infected, it loads viral
peptides with MHC I and displays them on the cell surface; if the infected host cell is
phagocytized, viral antigens complex with MHC I for presentation to TC cells.
T helper cells (TH cells) do not directly seek and destroy invaders; TH cells coordinate an
adaptive immune response by stimulating other white blood cells (e.g., B cells, macrophages,
2
ALL RIGHTS RESERVED.
Unit 3 Study Guide: Chapter 12 Exam
Questions With Verified Answers
Name the branches of adaptive immunity and compare adaptive to innate immunity. -
Answers✔Adaptive immunity includes cellular (T-cell-mediated immunity) and humoral (B-cell
antibody-mediated with some T-cell-mediation) responses. The goal of both branches is the
same: eliminate an antigen and remember it so that next time adaptive responses are faster.
Cellular and humoral responses both progress through four main stages: antigen presentation,
lymphocyte activation, lymphocyte proliferation and differentiation, and antigen elimination and
memory.
Adaptive immunity differs from innate responses because they take longer to mount (few days to
more than a week between detection and response in primary exposure), are specific to a
particular antigen, and exhibit memory (secondary exposure to same antigen is rapid and
effective, frequently will not experience disease symptoms while bodies eliminate pathogen).
Adaptive responses go into action when innate first- and second-line defenses fail to contain a
threat.
Compare and contrast T and B cells. - Answers✔T-cells:
-lymphocytes that are initially produced in bone marrow and mature in thymus
-mature T cells are present at relatively low levels in circulation; reside in lymphatic tissues
-each individual cell has thousands of receptors that can only recognize one epitope
-part of cellular immune response, help coordinate humoral response
-require antigen presenting cells (APCs) to show antigen
-recognize antigens due to gene shuffling mechanisms that randomly give rise to receptors
-undergo screening to select for immune cells with self-tolerance (inability to recognize MHCs
and potential self-reaction leads to apoptosis)
-chemical signals cause clonal expansion and differentiation into effector and memory cells; T
cells can become T cytotoxic cells or T helper cells
-have single-pronged T-cell receptors (TCRs)
1
, ©THEBRIGHT EXAM SOLUTIONS 2024/2025
ALL RIGHTS RESERVED.
-have MHC I proteins present on cell surface
-not considered antigen presenting cells
B-cells:
-lymphocytes that are produced and mature in bone marrow
-mature B cells are present at relatively low levels in circulation; reside in lymphatic tissues
-each individual cell has thousands of receptors that can only recognize on epitope; antibodies
released can only recognize one epitope
-part of humoral immune response only
-B cells do not require APCs to show them antigens; instead they can directly interact with an
antigen
-recognize antigens due to gene shuffling mechanisms that randomly give rise to receptors
-undergo screening to select for immune cells with self-tolerance (ability to make antibodies
against self-antigens leads to apoptosis)
-chemical signals cause clonal expansion and differentiation into effector and memory cells;
effector B cells are called plasma cells and they make antibodies—secreted form of B cell
receptor that binds to antigen that stimulated the activation event
-have MHC I and II protein
Compare and contrast T helper versus T cytotoxic cells and discuss the various T helper cell
subclasses. - Answers✔We can tell T cell lineages apart by presence of cluster of differentiation
(CD) proteins.
T cytotoxic cells (Tc cells) directly destroy infected or cancerous cells and transplant tissues. TC
cells are only in cell-mediated immunity. TC cells have CD8 proteins. TC cells interact with
MHC I presenting intracellular antigens. Only TC cells that have been trained by APCs to
recognize the given antigen can effectively patrol the body and eliminate cells displaying
suspicious antigens. To train TC cells, APCs obtain viral antigen samples by being infected with
the virus or by phagocytizing an infected host cell; if the APC is directly infected, it loads viral
peptides with MHC I and displays them on the cell surface; if the infected host cell is
phagocytized, viral antigens complex with MHC I for presentation to TC cells.
T helper cells (TH cells) do not directly seek and destroy invaders; TH cells coordinate an
adaptive immune response by stimulating other white blood cells (e.g., B cells, macrophages,
2
