Specific acquired immunity

Question 1

1. The initial complement component activated by complement-fixing antibodies is:

A C1q

B C1s

C C3b

D C5a

E C9

Answer 1

A C1q

Question 2

2. Several of the complement components are:

A Glycolipids

B Cell surface molecules of lymphocytes

C Precursors of enzymes

D Hormones

E Antibodies

Answer 2

C Precursors of enzymes

Question 3

3. The classical and alternative pathways meet at complement component:

A C4

B C4b

C Factor D

D C5

E C3

Answer 3

E C3

Question 4

4. Clonal selection occurs when antigen is encountered by:

A Neutrophils

B Mast cells

C T-cells

D Basophils

E Eosinophils

Answer 4

C T-cells

Question 5

5. Which of the following statements is TRUE of plasma cells?

A Plasma cells have a thin layer of cytoplasm

B Plasma cells are derived from T-cells

C Plasma cells develop into B-cells

D Plasma cells secrete large amounts of IFNγ

E Plasma cells have a high RNA content

Answer 5

E Plasma cells have a high RNA content

Question 6

6. Specific antibodies are readily detectable in serum following primary contact with antigen after:

A 10 min

B 1 h

C 5–7 days

D 3–5 weeks

E Only following a second contact with antigen

Answer 6

C 5–7 days

Question 7

7. A single plasma cell secretes:

A Antibody of a single specificity related to that on the surface of the parent B-cell

B Antibody of two antigen specificities

C The antigen it recognizes

D Many different types of antibody

E Lysozyme

Answer 7

A Antibody of a single specificity related to that on the surface of the parent B-cell

Question 8

8. Immunological memory can be transferred experimentally by:

A Antibody

B Complement

C Phagocytes

D Lymphocytes

E Serum

Answer 8

D Lymphocytes

Question 9

9. What is the main reason an experimental animal treated with X-rays can act as a living test tube for lymphocyte transfer experiments?

A It is microbiologically sterile

B Complement components will be inactivated

C The host lymphocytes are destroyed or unable to divide

D Only non-dividing cells are affected

E The requirement for T-cell help is overcome

Answer 9

C The host lymphocytes are destroyed or unable to divide

Question 10

10. What is immunological unresponsiveness to self-antigens called?

A Tolerance

B Tolerogen

C Memory

D Acquired immunity

E Antibody-dependent cellular cytotoxicity (ADCC)

Answer 10

A Tolerance

Question 11

11. Edward Jenner vaccinated against smallpox using:

A Killed smallpox virus

B A recombinant protein derived from smallpox

C An unrelated virus

D Toxoid

E Cowpox

Answer 11

E Cowpox

Question 12

12. Protective antibodies against infectious agents are often:

A Autoantibodies

B Neutralizing

C Toxoids

D Natural killer (NK)

E Non-specific

Answer 12

B Neutralizing

Question 13

13. Intracellular parasites within macrophages are killed more readily in the presence of:

A Antibody

B Kinins

C Properdin

D IFNγ

E Anaphylatoxin

Answer 13

D IFNγ

Question 14

14. T-cell surface receptors for antigen partly recognize:

A Cytokines

B Major histocompatibility complex (MHC)

C ADCC

D Antibody

E IL-2

Answer 14

B Major histocompatibility complex (MHC)

Question 15

15. An immune response against grass pollen often involves:

A Pathogen-associated molecular patterns (PAMPs)

B Breakdown of self-tolerance

C A hypersensitivity reaction

D Reaction against MHC

E Persistent infection by the pollen

Answer 15

C A hypersensitivity reaction

Question 16

16. Why are secondary antibody responses better?

A They provide defense against unrelated antigens

B The antibody can be made by both T- and B-cells

C Complement-fixing antibodies are made

D They do not require T-cell help

E They are stronger and faster

Answer 16

E They are stronger and faster

Question 17

17. Which cell type produces antibodies?

A Macrophages

B T-lymphocytes

C NK

D Plasma cells

E Eosinophils

Answer 17

D Plasma cells

Question 18

18. What is the single best defining description of the classical pathway of complement activation?

A It acts as a cascade

B It produces a C5 convertase

C In generates the membrane attack complex (MAC)

D It results in the splitting of C3 into C3a and C3b

E It utilizes complement component C1r

Answer 18

E It utilizes complement component C1r

Question 19

19. What is the single best defining feature of a lymphocyte?

A A type of leukocyte

B A cell that is specialized to produce cytokines

C Present in the circulation

D Antigen-specific

E Able to undergo cell proliferation

Answer 19

D Antigen-specific

Question 20

20. What is the characteristic that best defines the acquired immune response?

A It exhibits immunological memory

B It involves leukocytes

C It involves cell proliferation

D The cells involved recognize pathogens

E It is not present at birth

Answer 20

A It exhibits immunological memory