Host Defense and Innate Immunology

Question 1

2. What characterizes the first line of defense in host immunity? A) Specificity in
   targeting particular microbes B) Reliance on physical barriers only C) Prevention
   of invasion at the portal of entry D) Production of antibodies upon exposure to
   foreign substances

Answer 1

C) Prevention of invasion at the portal of entry

Question 2

1. Which of the following is considered a nonspecific defense mechanism of the
   host? A) Production of antibodies B) Inflammation C) Phagocytosis D) Activation
   of memory cells

Answer 2

B) Inflammation

Question 3

3. What is the primary function of the second line of defense in the immune
   system? A) Production of antibodies B) Phagocytosis and inflammation C)
   Creation of memory cells D) Recognition and differentiation of normal versus
   foreign material

Answer 3

B) Phagocytosis and inflammation

Question 4

4. Which of the following is an example of a physical or anatomical barrier in host
   immunity? A) Hydrochloric acid in the stomach B) Production of antibodies C)
   Activation of T cells D) Release of histamines during allergies

Answer 4

A) Hydrochloric acid in the stomach

Question 5

5. Genetic resistance to infection occurs when: A) Pathogens mutate to evade the
   host’s immune system B) The host lacks receptors necessary for pathogen
   adherence C) Host immune cells recognize and destroy foreign material D)
   Specific antibodies are produced upon exposure to a pathogen

Answer 5

B) The host lacks receptors necessary for pathogen adherence

Question 6

6. What are PAMPs? A) Specific antigens produced by pathogens B) Pathogens
   responsible for genetic resistance C) Molecules shared by microorganisms D)
   Proteins released by host cells during inflammation

Answer 6

C) Molecules shared by microorganisms

Question 7

7. Which type of white blood cell is primarily responsible for phagocytosis and is the first to attack an infection?
   A) Eosinophils B) Basophils C) Neutrophils D)Lymphocytes

Answer 7

C) Neutrophils

Question 8

8. What is the primary function of lymph nodes in the immune system? A) Filtering
   circulating blood to remove pathogens B) Production of antibodies C) Draining
   excess fluid from tissues D) Maturation of T cells

Answer 8

A) Filtering circulating blood to remove pathogens

Question 9

9. Which of the following is NOT an early immune response? A) Inflammation B)
   Fever C) Antibody production D) Phagocytosis

Answer 9

C) Antibody production

Question 10

10. What initiates fever as an adjunct to inflammation? A) Interleukin-1 (IL-1) and
    tumor necrosis factor (TNF) B) Activation of memory cells C) Release of
    histamines D) Migration of dendritic cells to lymph nodes

Answer 10

A) Interleukin-1 (IL-1) and tumor necrosis factor (TNF)

Question 11

11. Which of the following is NOT a benefit of fever in the immune response? A)
    Inhibition of multiplication of temperature-sensitive microorganisms B) Reduction
    of available iron for bacterial nutrition C) Suppression of immune reactions D)
    Stimulation of immune responses and physiological processes

Answer 11

C) Suppression of immune reactions

Question 12

12. What is the primary activity of phagocytes in the second line of defense? A) Production of antibodies B) Surveillance of tissue compartments C) Phagocytosis
    and elimination of foreign materials D) Activation of B cells

Answer 12

C) Phagocytosis and elimination of foreign materials

Question 13

13. Which type of white blood cell is attracted to sites of parasitic infections and
    antigen-antibody reactions? A) Neutrophils B) Eosinophils C) Monocytes D)
    Basophils

Answer 13

B) Eosinophils

Question 14

14. What is the primary role of Toll-like receptors (TLRs) in phagocytosis? A)
    Recognition of self-cells B) Phagosome formation C) Binding to pathogen-
    associated molecular patterns (PAMPs) D) Release of cytokines

Answer 14

C) Binding to pathogen-associated molecular patterns (PAMPs)

Question 15

15. What is the final step in the process of phagocytosis? A) Phagocyte migration to
    inflammation B) Binding of PAMPs to TLRs C) Formation of a phagolysosome D)
    Release of antimicrobial substances

Answer 15

C) Formation of a phagolysosome

Question 16

16. Which of the following is true about interferons? A) They are specific proteins
    produced by bacteria. B) They induce the expression of cancer genes. C) They
    inhibit viral replication. D) They only bind to B cells

Answer 16

C) They inhibit viral replication

Question 17

17. What are the primary functions of a healthy immune system? A) Surveillance of
    the body, recognition of self-cells, and attack against pathogens B) Recognition
    and differentiation of normal versus foreign material C) Production of antibodies
    and activation of memory cells D) Destruction of all foreign material without
    discrimination

Answer 17

B) Recognition and differentiation of normal versus foreign material

Question 18

18. Which of the following is NOT an anatomical barrier in host immunity? A)
    Hydrochloric acid in the stomach B) Acidic pH in the vagina C) Production of
    antibodies D) Intact skin

Answer 18

C) Production of antibodies

Question 19

19. What is the primary role of lymphatic fluid in the immune system? A)
    Transporting nutrients to cells B) Filtering pathogens from the blood C) Providing
    a route for the inflammatory response D) Draining excess fluid from tissues

Answer 19

C) Providing a route for the inflammatory response

Question 20

20. What is the function of dendritic cells in the immune system? A) Release of
    histamines during allergies B) Production of antibodies C) Migration to lymph
    nodes to activate T and B cells D) Phagocytosis and elimination of foreign
    materials

Answer 20

C) Migration to lymph nodes to activate T and B cells

Question 21

21. What is the primary function of the thymus in the immune system? A) Filtering
    circulating blood B) Maturation of T cells C) Production of antibodies D)
    Activation of memory cells

Answer 21

B) Maturation of T cells

Question 22

22. Which of the following is NOT a characteristic of neutrophils? A) They are the
    first to attack an infection. B) They contain lavender granules. C) They are
    primarily responsible for allergic reactions. D) They are phagocytic cells.

Answer 22

C) They are primarily responsible for allergic reactions

Question 23

23. What is the primary role of basophils in host immunity? A) Phagocytosis B)
    Release of chemicals to destroy invaders C) Production of antibodies D)
    Maturation of T cells

Answer 23

B) Release of chemicals to destroy invaders

Question 24

24. Which type of white blood cell is responsible for mediating allergies? A)
    Eosinophils B) Neutrophils C) Basophils D) Lymphocytes

Answer 24

C) Basophils

Question 25

25. What is the function of mast cells during allergies? A) Phagocytosis B) Release
    of histamines C) Production of antibodies D) Maturation of T cells

Answer 25

B) Release of histamines

Question 26

26. What is the primary function of dendritic cells in the immune system? A)
    Phagocytosis and elimination of foreign materials B) Production of antibodies C)
    Migration to lymph nodes to activate T and B cells D) Release of histamines
    during allergies

Answer 26

C) Migration to lymph nodes to activate T and B cells

Question 27

27. Which of the following is NOT an early immune response? A) Phagocytosis B)
    Interferon production C) Antibody production D) Inflammation

Answer 27

C) Antibody production

Question 28

28. What initiates the inflammatory response in tissues? A) Release of antibodies B)
    Activation of T cells C) Chemical signals from damaged cells or invading
    microbes D) Migration of dendritic cells

Answer 28

C) Chemical signals from damaged cells or invading microbes

Question 29

29. What is the purpose of chemotaxis during inflammation? A) Binding of PAMPs to
    TLRs B) Migration of cells out of blood vessels into tissues C) Phagocytosis and
    elimination of foreign materials D) Attracting white blood cells to the site of
    infection

Answer 29

D) Attracting white blood cells to the site of infection

Question 30

30. Which of the following is NOT a benefit of fever in the immune response? A)
    Stimulation of immune reactions B) Inhibition of multiplication of temperature-
    sensitive microorganisms C) Reduction of available iron for bacterial nutrition D)
    Suppression of phagocytosis

Answer 30

D) Suppression of phagocytosis

Question 31

31. What is the primary activity of phagocytes in the second line of defense? A) Production of antibodies B) Surveillance of tissue compartments C) Phagocytosis
    and elimination of foreign materials D) Activation of B cells

Answer 31

C) Phagocytosis and elimination of foreign materials

Question 32

32. What is the final step in the process of phagocytosis? A) Phagocyte migration to
    inflammation B) Binding of PAMPs to TLRs C) Formation of a phagolysosome D)
    Release of antimicrobial substances

Answer 32

C) Formation of a phagolysosome

Question 33

33. Which type of white blood cell is attracted to sites of parasitic infections and
    antigen-antibody reactions? A) Neutrophils B) Eosinophils C) Monocytes D)
    Basophils

Answer 33

B) Eosinophils

Question 34

34. What is the primary role of Toll-like receptors (TLRs) in phagocytosis? A)
    Recognition of self-cells B) Phagosome formation C) Binding to pathogen-
    associated molecular patterns (PAMPs) D) Release of cytokines

Answer 34

C) Binding to pathogen-associated molecular patterns (PAMPs)