Deck 34: Innate and Adaptive Immune Responses to Virus Infection

Question 1

Which of the following is NOT a peripheral or secondary lymphoid organ?

A)Tonsils
B)Thymus
C)Lymph node
D)Spleen
E)Peyer's patches

Answer 1

B

Question 2

What happens when the T cell receptor on a CD8 positive T cell recognizes the peptide displayed in the MHC-I complex on an infected cell?

A)It attracts natural killer cells,which kill the infected cell.
B)It releases interferon $\gamma$ which stimulates macrophages to engulf the cell.
C)It releases IL-4 to stimulate the B cells to release antibodies.
D)It releases proteins that kill the infected cell.
E)It releases IL-12 which stimulates the production of Th1 cells.

Answer 2

It releases proteins that kill the infected cell.

Question 3

Which of the following describes the process of antibody-dependent cellular cytotoxicity?

A)An antibody activates the Fas receptor on the infected cell and causes it to enter apoptosis.
B)An antibody causes the virus to be killed by a cytotoxic T lymphocyte.
C)An antibody binds to a virus particle and it is engulfed by a macrophage.
D)An antibody binds to a virally infected cell and it is attacked by a macrophage.
E)Both "c" and "d" are correct

Answer 3

E

Question 4

Myxoma virus,a rabbit poxvirus,produces a viroceptor that is a homologue of the interferon- $\gamma$ receptor.What purpose does this serve the virus?

A)It sequesters the interferon- $\gamma$ .
B)It stimulates the host cells to divide.
C)It enhances the release of virus particles from the infected cell.
D)It increases virus replication.
E)It prevents the MHC-I protein from displaying viral peptides.

Question 5

Which of the following describes the primary role of Th1 cells in modulating the immune response?

A)They present foreign antigens to B and T cells.
B)They engulf virus particles and present peptides on MHC-II.
C)They release cytokines that stimulate differentiation of cytotoxic T cells.
D)They release cytokines that stimulate a B cell to differentiate into a plasma cell.
E)They recognize and kill virus infected cells.

Question 6

Which of the following statements about MHC class I molecules is FALSE?

A)They are located on the surface of all cells in the body.
B)They are used to identify the cells as belonging to the host (self-identification).
C)They are recognized by natural killer cells.
D)They present cytoplasmic peptides to cytotoxic T lymphocytes.
E)They are recognized by B lymphocytes.

Question 7

Which of the following is NOT a component of the adaptive immune response system?

A)B lymphocytes
B)Helper T lymphocytes
C)Cytotoxic T lymphocytes
D)Complement system
E)Antibodies

Question 8

Pathogen specific B and T lymphocytes are mostly localized in specialized organs of the lymphatic system.

Question 9

Which of the following events causes a naïve T lymphocyte to become activated and differentiate into an effector T cell?

A)The T cell receptor recognizes its epitope on a peptide presented on MHC-I.
B)The T cell receptor recognizes its epitope on a peptide presented on MHC-II
C)A T helper cell releases IL-12 and causes it to differentiate.
D)A macrophage releases IL-4 and causes it to differentiate.
E)The T cell interacts with a B cell that recognizes the same epitope.

Question 10

Which of the following describes the structure of the B-cell receptor?

A)It is a type I trans-membrane protein.
B)It is a type II trans-membrane protein.
C)It is a membrane bound form of an antibody molecule.
D)It is composed of two polypeptides,one of which has a trans-membrane domain.
E)It is composed of two polypeptides,both of which contain trans-membrane domains.

Question 11

Which of the following is NOT an activity associated with interferon $\gamma$ ?

A)Induces the expression of MHC class II proteins.
B)Enhances the processing of viral proteins into peptides.
C)Induces the differentiation of natural killer cells.
D)Stimulates development of Th1 cells.
E)Stimulates activation of macrophages.

Question 12

The binding of an antibody to a virus particle allows it to be phagocytosed by a macrophage.Which of the following describes the mechanism by which this occurs?

A)The antibody makes the virus particle large enough to be detected by the macrophage.
B)The macrophage has a receptor that binds to the constant region of the antibody.
C)The antibody activates the complement system.
D)The antibody causes the virus particle to be lysed in the endosome.
E)The antibody causes the virus particle to bind to MHC-I

Question 13

The complement system is only effective at attacking bacterial infections but has no role in fighting off viral infections.

Question 14

Which of the following is a situation where an NK cell can recognize a virally infected cell and kill it?

A)The plasma membrane contains viral glycoproteins.
B)The NK cell recognizes the MHC-I complex on the surface.
C)The infected cell displays peptides on MHC-I complexes on its surface
D)The infected cell has a reduced amount of MHC proteins on its surface.
E)The NK cell recognizes the virus host cell receptor on the surface of the cell.

Question 15

Which of the following is NOT a component of the innate immune response system?

A)Cytotoxic T lymphocytes
B)Complement system
C)Natural killer cells
D)Polymorphonuclear leukocytes
E)Macrophages

Question 16

Which of the following is the receptor that differentiates a cytotoxic T lymphocyte from a helper T lymphocyte?

A)CD8 receptor
B)CD4 receptor
C)MHC class I
D)T cell receptor
E)B cell receptor

Question 17

Antibodies are produced by CD4 positive T lymphocytes.

Question 18

Which of the following types of immunoglobulin molecules is the first to be made during an immune response to a virus infection?

A)IgA
B)IgD
C)IgE
D)IgG
E)IgM

Question 19

Which of the following is NOT an antigen presenting cell?

A)Cytotoxic T lymphocyte
B)Macrophage
C)Dendritic cell
D)B lymphocyte
E)All of the above are antigen presenting cells.

Question 20

Many viruses reduce the amount of MHC-I complex on the surface of the infected cell.How does the immune system recognize cells that lack MHC-I?

A)Cytotoxic T lymphocytes will recognize the lack of MHC-I on the surface and kill the cell
B)Macrophages will recognize an antibody bound to MHC-I and engulf the cell.
C)Natural killer cells will kill cells that lack MHC-I on their surface.
D)Cells that don't have enough MHC-I on their surface will enter apoptosis and die.
E)Cytotoxic T lymphocytes will recognized the altered MHC-I on the cell surface.

Question 21

Antigenic drift allows viruses to evade both humoral and cellular immune defenses.

Question 22

Explain why it is more difficult for the immune system to detect and destroy viruses than bacteria.Describe the primary mechanism used by the adaptive immune response to overcome this obstacle.

Question 23

A single plasma cell can secrete two different antibodies that recognize different epitopes.

Question 24

Explain how B and T lymphocytes produced a variety of cell surface receptors that can bind a wide variety of epitopes on antigens.How is this related to the clonal selection theory?

Question 25

The constant region of an antibody molecule is only located on the light chain.

Question 26

Antigen presenting cells,like dendritic cells,interact with naïve T and B lymphocytes in the lymph nodes.

Question 27

The IgG molecule is the most abundant immunoglobulin produced during an immune response.