1
Introduction to Immunity and the
Immune System
Christine Dorresteyn Stevens, edd, MT(ASCP)
LEARNING OUTCOMES
After finishing this chapter, you should be able to:
1. Discuss how immunology as a science began with the
study of immunity.
2. Describe what is meant by an attenuated vaccine.
3. Explain how the controversy over humoral versus cellular
immunity contributed to expanding knowledge in the field of
immunology.
4. Contrast innate and adaptive immunity.
5. Describe the types of white blood cells (wbcs) capable
of phagocytosis.
6. Discuss the roles of macrophages, mast cells, and dendritic
cells in the immune system.
7. Identify the two primary lymphoid organs and discuss the
main functions of each.
8. List four secondary lymphoid organs and discuss their
overall importance to immunity.
9. Describe the function and architecture of a lymph node.
10. Compare a primary and a secondary follicle.
11. Define “cluster of differentiation” (CD).
12. Differentiate the roles of T cells and B cells in the immune response.
13. Discuss how natural killer (NK) cells differ from T lymphocytes.
, Third day, she noticed that the area around one earlobe was red
and slightly swollen.
Questions
a. Are the girl’s symptoms most likely caused by innate
immunity or adaptive immunity?
b. What types of cells would you expect to see in the affected
earlobe tissue?
2. You and a friend are discussing the relative merits of
immunizations. Your friend says that he doesn’t want to get a
tetanus booster shot because he has a good immune system and
his natural defenses will take care of any possible infection. You
have just been studying this subject in your immunology class.
Questions
a. What argument could you make to convince him that a
tetanus booster is a good idea?
b. What would you tell him about the types of cells involved in
the response to a vaccine?
REVIEW QUESTIONS
1. Pasteur’s discovery of attenuated vaccines is based on which of the
following principles?
a. Attenuated vaccines mainly stimulate the innate immune system.
b. Attenuated vaccines usually cause severe disease.
c. Attenuated pathogens are changed to become less virulent.
d. Attenuated pathogens are stronger than unchanged ones.
2. Which WBC is capable of further differentiation in tissues?
a. Neutrophil
b. Eosinophil
c. Basophil
d. Monocyte
,3. The cells that Metchnikoff first observed are associated with
which phenomenon?
a. Innate immunity
b. Adaptive immunity
c. Humoral immunity
d. Specific immunity
4. Where are all undifferentiated lymphocytes made?
a. Bone marrow
b. Spleen
c. Thymus
d. Lymph nodes
5. How do NK cells differ from T cells?
a. NK cells are better at phagocytosis than T cells.
b. NK cells require the thymus for development, and T cells do not.
c. Only NK cells are found in lymph nodes.
d. Only NK cells are able to kill target cells without prior
exposure to them.
6. Which cell is the most potent phagocytic cell in the tissue?
a. Neutrophil
b. Dendritic cell
c. Eosinophil
d. Basophil
7. The ability of an individual to resist infection by means of
normally present body functions is called
a. Innate immunity.
b. Humoral immunity.
c. Adaptive immunity.
d. Cross-immunity.
, 8. A cell characterized by a nucleus with two to five lobes, a
diameter of 10 to 15 µm, and a large number of neutral-
staining granules is identified as a(n)
a. Eosinophil.
b. Monocyte.
c. Basophil.
d. Neutrophil.
9. Which of the following is a primary lymphoid organ?
a. Lymph node
b. Spleen
c. Thymus
d. MALT
10. What type of cells would be found in a primary follicle?
a. Unstimulated B cells
b. Germinal centers
c. Plasma cells
d. Memory cells
11.Which of the following is a distinguishing feature of B cells?
a. Act as helper cells
b. Presence of surface antibody
c. Able to kill target cells without prior exposure
d. Active in phagocytosis
12. Where do lymphocytes mainly come in contact with antigens?
a. Secondary lymphoid organs
b. Bloodstream
c. Bone marrow
d. Thymus
Introduction to Immunity and the
Immune System
Christine Dorresteyn Stevens, edd, MT(ASCP)
LEARNING OUTCOMES
After finishing this chapter, you should be able to:
1. Discuss how immunology as a science began with the
study of immunity.
2. Describe what is meant by an attenuated vaccine.
3. Explain how the controversy over humoral versus cellular
immunity contributed to expanding knowledge in the field of
immunology.
4. Contrast innate and adaptive immunity.
5. Describe the types of white blood cells (wbcs) capable
of phagocytosis.
6. Discuss the roles of macrophages, mast cells, and dendritic
cells in the immune system.
7. Identify the two primary lymphoid organs and discuss the
main functions of each.
8. List four secondary lymphoid organs and discuss their
overall importance to immunity.
9. Describe the function and architecture of a lymph node.
10. Compare a primary and a secondary follicle.
11. Define “cluster of differentiation” (CD).
12. Differentiate the roles of T cells and B cells in the immune response.
13. Discuss how natural killer (NK) cells differ from T lymphocytes.
, Third day, she noticed that the area around one earlobe was red
and slightly swollen.
Questions
a. Are the girl’s symptoms most likely caused by innate
immunity or adaptive immunity?
b. What types of cells would you expect to see in the affected
earlobe tissue?
2. You and a friend are discussing the relative merits of
immunizations. Your friend says that he doesn’t want to get a
tetanus booster shot because he has a good immune system and
his natural defenses will take care of any possible infection. You
have just been studying this subject in your immunology class.
Questions
a. What argument could you make to convince him that a
tetanus booster is a good idea?
b. What would you tell him about the types of cells involved in
the response to a vaccine?
REVIEW QUESTIONS
1. Pasteur’s discovery of attenuated vaccines is based on which of the
following principles?
a. Attenuated vaccines mainly stimulate the innate immune system.
b. Attenuated vaccines usually cause severe disease.
c. Attenuated pathogens are changed to become less virulent.
d. Attenuated pathogens are stronger than unchanged ones.
2. Which WBC is capable of further differentiation in tissues?
a. Neutrophil
b. Eosinophil
c. Basophil
d. Monocyte
,3. The cells that Metchnikoff first observed are associated with
which phenomenon?
a. Innate immunity
b. Adaptive immunity
c. Humoral immunity
d. Specific immunity
4. Where are all undifferentiated lymphocytes made?
a. Bone marrow
b. Spleen
c. Thymus
d. Lymph nodes
5. How do NK cells differ from T cells?
a. NK cells are better at phagocytosis than T cells.
b. NK cells require the thymus for development, and T cells do not.
c. Only NK cells are found in lymph nodes.
d. Only NK cells are able to kill target cells without prior
exposure to them.
6. Which cell is the most potent phagocytic cell in the tissue?
a. Neutrophil
b. Dendritic cell
c. Eosinophil
d. Basophil
7. The ability of an individual to resist infection by means of
normally present body functions is called
a. Innate immunity.
b. Humoral immunity.
c. Adaptive immunity.
d. Cross-immunity.
, 8. A cell characterized by a nucleus with two to five lobes, a
diameter of 10 to 15 µm, and a large number of neutral-
staining granules is identified as a(n)
a. Eosinophil.
b. Monocyte.
c. Basophil.
d. Neutrophil.
9. Which of the following is a primary lymphoid organ?
a. Lymph node
b. Spleen
c. Thymus
d. MALT
10. What type of cells would be found in a primary follicle?
a. Unstimulated B cells
b. Germinal centers
c. Plasma cells
d. Memory cells
11.Which of the following is a distinguishing feature of B cells?
a. Act as helper cells
b. Presence of surface antibody
c. Able to kill target cells without prior exposure
d. Active in phagocytosis
12. Where do lymphocytes mainly come in contact with antigens?
a. Secondary lymphoid organs
b. Bloodstream
c. Bone marrow
d. Thymus
