Deck 41: Immune Systems

Question 1

The allergic response is primarily mediated by _____ antibodies.

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

Answer 1

D

Question 2

Class I MHC (major histocompatibility complex)is NOT important in

A)fighting cancer.
B)recognizing infected cells.
C)identifying bacterial pathogens.
D)identifying abnormal cells.
E)presenting antigenic determinants.

Answer 2

C
Explanation: Unlike helper T cells,cytotoxic T cells require class I MHC proteins for activation.This distinction helps explain the major function of cytotoxic T cells-destruction of any of the body's own altered cells that have become cancerous or infected with viruses.The crucial point is that the antigens that complex with class I MHC proteins typically arise within body cells and are thus endogenous antigens.

Question 3

Which of the following statements about antibody-mediated immunity is CORRECT?

A)It primarily defends against viruses that have already infected cells.
B)It is responsible for transplant tissue rejection.
C)It protects the body against cells that become cancerous.
D)It defends against parasites,bacteria,and viruses.
E)It primarily defends against bacteria that have already infected cells.

Answer 3

D

Question 4

Which of the following is true of both T cells and B cells?

A)They produce effector cells against specific pathogens.
B)They are produced from stem cells of the lymphatic system.
C)They can attack and destroy invading pathogens.
D)They typically have a short life span.
E)All of these statements are truE.

Question 5

Your patient becomes sick due to an infection by the influenza virus and now has the flu.The cells which would most directly attack and lyse virally infected host cells in this case are __________.These cells mature in the __________.

A)T cells;bone marrow
B)B cells;thymus
C)T cells;lymph nodes
D)B cells;spleen
E)T cells;thymus

Question 6

During the inflammatory response,dilation of blood vessels is caused by

A)nitric oxide.
B)histamine.
C)cytokines.
D)phagocytes.
E)both histamine and nitric oxidE.

Question 7

A doctor discovers that her patient can produce antibodies against some bacterial pathogens,but he is unable to protect himself against viral infections.The doctor suspects a disorder in her patient's

A)B cells.
B)plasma cells.
C)cytotoxic T cells.
D)suppressor T cells.
E)macrophages.

Question 8

_________ is a characteristic of the early stages of a local inflammation response.

A)Arteriole constriction
B)Fever
C)Attack by cytotoxic T cells
D)Release of histamines
E)Release of CD4

Question 9

Which of the following is TRUE of both T cells and B cells?

A)They are lymphocytes.
B)They recognize specific antigens on the cell surface.
C)When activated,they proliferate to form both effector cells and memory cells.
D)They are involved in the humoral immune response.
E)All of the responses are correct.

Question 10

To infect a cell,HIV must

A)bind both CD4 and a cytokine receptor.
B)bind both CD8 and a cytokine receptor.
C)bind both CD8 and a class I MHC protein.
D)kill cytotoxic T cells and bind CD4.

Question 11

HIV infection and the subsequent destruction of which cell type is most devastating to overall immune system function?

A)cytotoxic T cells
B)memory B cells
C)helper T cells
D)monocytes
E)natural killer cells

Question 12

Generally speaking,vaccinations are effective in combating future infections because they induce the production of

A)helper T cells.
B)neutrophils.
C)prostaglandins.
D)mutations in the host genome.
E)memory cells.

Question 13

In mammalian defenses against invading pathogens,all of these are considered nonspecific defense mechanisms EXCEPT

A)acquired immunity.
B)the skin.
C)mucous membranes.
D)the inflammatory response.
E)antimicrobial proteins (E.g. ,interferon).

Question 14

The protection provided through transfer of antibodies from mother to fetus is an example of

A)active immunity.
B)passive immunity.
C)cell-mediated immunity.
D)clonal selection.
E)autoimmunity.

Question 15

Antigens are

A)non-self proteins.
B)proteins on the surface of B-cell membranes.
C)proteins that consist of two light and two heavy chain polypeptide chains.
D)proteins on the surface of macrophage membranes.
E)proteins on the surface of T-cell membranes.

Question 16

All of the following are components of nonspecific immunity EXCEPT

A)skin.
B)phagocytes.
C)complement.
D)lysozyme.
E)B cells.

Question 17

Which of the following is NOT involved in nonspecific defenses?

A)natural killer cells
B)monocytes
C)neutrophils
D)mast cells
E)B cells

Question 18

It is estimated that humans can produce over 1.5 million different types of antibodies.Which of the following statements regarding this extraordinary variation is INCORRECT?

A)We inherit over 1.5 million different and distinct immunoglobulin genes from our parents at fertilization.
B)V and J domains of antibody light chains are randomly joined.
C)Random segments of DNA can be removed from antibody genes.
D)V and J domains of antibody heavy chains are randomly joineD.
E)Cytosines in the variable regions of antibody genes can be converted to uracils via hypermutation.

Question 19

Most allergy medicines contain antihistamines that block the actions of histamine.These drugs reduce cold symptoms by directly

A)lysing virus-infected cells to prevent further propagation of the pathogen.
B)stimulating components of the immune system through the release of cytokines.
C)reducing the inflammation response.
D)stimulating the production of specific antibodies.
E)recruiting macrophages to the nasal epithelium.

Question 20

The clonal selection theory implies that

A)related people have similar immune responses.
B)antigens activate specific lymphocytes.
C)only certain cells can produce interferon.
D)memory cells are present at birth.
E)the body selects which antigens it will respond to.

Question 21

Which of the following is NOT a part of the lymphatic system?

A)Tonsils
B)Spleen
C)Lymph node
D)Bone marrow
E)Pancreas

Question 22

Breastfeeding confers immunological benefits to the baby.

Question 23

Cytotoxic T cells destroy cancerous cells by

A)forming the membrane attack complex.
B)releasing vesicles containing proteases and perforin.
C)activating natural killer cells.
D)opsonization.
E)secreting cytokines.

Question 24

Helper T cells activate both B cells and cytotoxic T cells.

Question 25

Which option would be the LEAST effective initial line of defense against pathogens?

A)Thin,unkeratinized skin of a salamander
B)Strong stomach acid
C)Thick mucus coating the trachea
D)Lysosomes in the fluid bathing the eye
E)Exoskeleton of a beetle

Question 26

Strategies to fight HIV include

A)inhibition of the reverse transcriptase enzyme.
B)inhibition of virus assembly.
C)prevention of HIV entering healthy cells.
D)prevention of other infections.
E)a combination of all of the abovE.

Question 27

What would the result be if histamine and nitric oxide were NOT secreted during a puncture injury?

A)Helper T cells could not be signaled.
B)The blood vessels would be more permeable.
C)The mast cells constrict.
D)Healing would be slower.
E)Healing would not take place at all.

Question 28

Recall Bruno Lemaitre's experiment on Toll protein in Drosophila.In a similar experiment,you wanted to test a single fruit fly for the presence of the Toll protein,so you prick it with a needle coated in fungal spores.The fly dies a week later.Which of the following statements is TRUE?

A)This is evidence that the Toll protein is present.
B)This is evidence that the Toll protein is not present.
C)The Toll protein is only found in humans.
D)This is inconclusive evidence.

Question 29

Specific immunity in the extracellular fluid is provide by mainly

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

Question 30

Immunoglobulins counteract microbes in all of the following ways EXCEPT which?

A)perforating the microbial cell membrane
B)binding toxins
C)linking microbes to complement proteins
D)linking microbes to phagocytes
E)linking microbes to NK cells

Question 31

The three major types of pathogens are bacteria,viruses,and cancer.

Question 32

Which of the following lifestyle changes would NOT boost the immune system?

A)reducing stress by practicing yoga
B)walking 20 minutes a day
C)getting at least 8 hours of sleep
D)reducing inflammation by using a cortisol supplement
E)All of these actions will boost the immune system

Question 33

You are trying to develop a new anti-inflammatory medication.Which of the following would be a possible approach?

A)suppressing cytokine release
B)blocking vasodilation
C)preventing leukocyte movement through the capillary wall
D)suppressing the release of nitric oxide from endothelial cells
E)All of these approaches would have an anti-inflammatory effect.

Question 34

Which of the following pairs is incorrectly matched?

A)macrophage;class II MHC protein
B)B cell;immunoglobulin
C)B cell;IL-2
D)helper T cell;CD4
E)cytotoxic T cell;CD8

Question 35

Antigen-presenting cells include

A)macrophages.
B)macrophages and B cells.
C)dendritic cells and macrophages.
D)dendritic cells and B cells.
E)macrophages,B cells and dendritic cells.

Question 36

The first stage of a specific immune response is the proliferation of B cells and T cells.

Question 37

Plasma cells

A)produce antibodies.
B)kill infected cells.
C)mature in the thymus.
D)remain present in the body at low levels after an infection.
E)secrete cytokines.

Question 38

Which of the following is NOT an autoimmune disease?

A)multiple sclerosis
B)type I diabetes
C)rheumatoid arthritis
D)HIV
E)All of these conditions are autoimmune diseases.

Question 39

The membrane attack complex is involved in specific immune defense mechanisms.

Question 40

Humoral immunity is mostly the function of

A)cytotoxic T cells.
B)B cells.
C)Class I MHC.
D)complement cells.
E)mast cells.

Question 41

The 1918 influenza pandemic was notable for the number of people who died,particularly young people with healthy immune systems.Scientists believe that the deaths may have been caused by an overreaction of the immune system to infection.An out-of-control positive feedback loop can occur,because helper T cells and macrophages can both respond to and also secrete __________.

A)cytokines
B)immunoglobulins
C)perforin
D)proteases
E)T cell receptors

Question 42

What is part of the body's initial line of defense against pathogens?

A)Phagocytes
B)Mucous membranes
C)B cells
D)Memory T cells
E)Cytokines

Question 43

Most innate immune responses rely on

A)recognition of specific antigens.
B)pathogens being engulfed and destroyed.
C)plasma cells to secrete antibodies.
D)IgM antibodies.
E)clonal selection to replicate specific lymphocytes.

Question 44

HIV is devastating to the immune system because it destroys helper T cells,which are important for both humoral and cell-mediated immunity.If both humoral and cell-mediated immunity are nonfunctional,the body has no remaining defense against pathogens.

Question 45

Phagocytosis is a process in which a cell

A)takes in foreign particles and destroys them.
B)creates molecules and then excretes them.
C)lyses itself.
D)merges with another cell forming antibodies.
E)adheres to another cell.

Question 46

IgA antibodies are involved in innate immunity.

Question 47

Recent research has shown that anti-inflammatory drugs can impair immune response to a vaccination.This makes sense since __________ participate in the inflammation response,and also act as APCs to present antigens to __________ that in turn activate __________ which produce antibodies.

A)macrophages;cytotoxic T cells;helper T cells
B)mast cells;helper T cells;macrophages
C)neutrophils;cytotoxic T cells;B cells
D)macrophages;helper T cells;B cells

Question 48

During inflammation,blood vessels are constricted to prevent leakage.

Question 49

Most bacteria damage the body by infecting cells and multiplying within them.

Question 50

A certain virus has evolved a novel virus coat protein that has never existed before.Which of the following molecules will still be able to bind this novel antigen? (Check all that apply. )
__X__ immunoglobulin
_____ perforin
__X__ T-cell receptor
_____ Toll-like receptor

Question 51

PAMP is an enzyme involved in creating immunoglobulin light chains.