Deck 23: The Immune System

Question 1

In order to be completely functional, a T cell must be activated by

A) the lymph nodes.
B) bone marrow.
C) the parathyroid gland.
D) the thymus gland.
E) the thyroid gland.

Answer 1

D

Question 2

Which of the following is NOT considered a peripheral lymphoid tissue?

A) adenoids
B) appendix
C) tonsils
D) bone marrow
E) spleen

Answer 2

D

Question 3

What type of cell found in the skin and mucosal linings secretes histamine?

A) mast cell
B) basophil
C) macrophage
D) dendritic cell
E) monocyte

Answer 3

A

Question 4

What type of cell, once it enters the tissues, is converted into a macrophage that attacks invaders by phagocytosis?

A) monocyte
B) eosinophil
C) neutrophil
D) lymphocyte
E) basophil

Question 5

At the site of infection, leukocytes are stimulated to express to the endothelial cells before moving into the vessel wall.

A) selectins
B) marginin
C) chemotactic factor
D) attachins
E) integrins

Question 6

Which of the following is NOT one of the body's nonspecific defenses against pathogens?

A) natural killer cell
B) cytotoxic T cell
C) complement system
D) interferons
E) inflammation

Question 7

The increase in blood flow to a site of infection acts to

A) bring more mast cells to the site of infection.
B) facilitate the migration of the leukocytes into the interstitial space.
C) increase oxygen in the region to kill the invading bacteria.
D) wash the invading bacteria from the region of the infection.
E) recruit more leukocytes to the site of infection.

Question 8

What causes the increase in interstitial osmotic pressure that occurs during edema?

A) leukocyte migration
B) stimulation of sensory neurons
C) recruitment of leukocytes
D) increased blood flow
E) increased capillary permeability

Question 9

While is released early in the inflammatory response to inhibit blood clotting, the that have leaked into the interstitial space become active and isolate the region of damage.

A) bradykinin : defensive proteins
B) heparin : clotting factors
C) bradykinin : albumin molecules
D) histamine : clotting factors
E) histamine : defensive proteins

Question 10

Which of the following is NOT one of the four steps involved in phagocytosis?

A) internalization
B) attachment
C) exocytosis
D) degradation
E) interleukin release

Question 11

Which of the following steps initiates an inflammatory response?

A) Macrophages engulf the debris or foreign material.
B) Capillary permeability increases.
C) Leukocytes migrate to the infection.
D) Arterioles dilate.
E) Macrophages secrete cytokines.

Question 12

Most null cells are destined to become what type of cell?

A) mast cells
B) plasma cells
C) natural killer cells (NK cells)
D) dendritic cells
E) effector cells

Question 13

When a B cell contacts a foreign or abnormal antigen, it develops into a .

A) natural killer cell : antibodies
B) plasma cell : histamine
C) plasma cell : antibodies
D) macrophage : histamine
E) macrophage : antibodies

Question 14

What type of cell is important in fighting the early stages of viral infections?

A) natural killer cells (NK cells)
B) effector cells
C) plasma cells
D) dendritic cells
E) mast cells

Question 15

Leukocyte movement from blood to the site of tissue damage or infection involves , leukocyte movement toward the blood vessel wall; _ , the movement of leukocytes between
Endothelial cells of the blood vessel; and injury.

A) diapedesis : margination : chemotaxis
B) chemotaxis : margination : diapedesis
C) margination : diapedesis : chemotaxis
D) margination : chemotaxis : diapedesis
E) chemotaxis : diapedesis : margination

Question 16

What are phagocytic leukocytes that attack parasitic cells by releasing toxic molecules once they have attached themselves to the parasite?

A) neutrophils
B) eosinophils
C) macrophages
D) basophils
E) monocytes

Question 17

The immune system consists of two components:

A) plasma cells : cytotoxic T cells
B) leukocytes : lymphoid tissues
C) leukocytes : lymphocytes
D) lymphocytes : phagocytes
E) antigens : antibodies

Question 18

The increase in interstitial hydrostatic pressure associated with an edema will lead to a(n)

A) sensation of pain.
B) increase in blood flow.
C) increased movement of water out of the capillaries.
D) decrease in the recruitment of leukocytes to the site of infection.
E) release of bradykinin.

Question 19

Which of the following is NOT one of the four classic symptoms of inflammation?

A) heat
B) pain
C) swelling
D) rash
E) redness

Question 20

Mucus secreted by mucous membranes provides protection against infections by

A) forcing the pathogen to die in the struggle to free itself (like a fly strip).
B) trapping and removing pathogens.
C) drowning the pathogen.
D) phagocytosing pathogens by macrophages.
E) destroying pathogens by the complement system.

Question 21

Which of the following is NOT a characteristic of a primary immune response?

A) It requires 10 -17 days to initiate.
B) The response is especially strong.
C) Antigen -selected B or T cells differentiate into effector cells.
D) The response is short -lived.
E) Antigen -selected B or T cells proliferate.

Question 22

What are different recognition sites on the same antigen called?

A) variable regions
B) perforins
C) epitopes
D) antigen
E) alleles

Question 23

Which of the following is NOT an action of interleukins released by phagocytic cells?

A) acting as endogenous pyrogens to increase body temperature
B) stimulation of the release of neutrophils from bone marrow
C) acting as opsonins to facilitate phagocytosis
D) increasing endothelial cell synthesis of adhesion molecules
E) stimulating the production of acute phase proteins from the liver

Question 24

Phagocyte attachment to a pathogen is enhanced by a process known as

A) chemotaxis.
B) diapedesis.
C) leukocytosis.
D) opsonization.
E) margination.

Question 25

Recruited leukocytes that have invaded the vessel wall are directed to the pathogen by the process of

A) chemotaxis.
B) attachment.
C) migration.
D) opsonization.
E) diapedesis.

Question 26

The antigen -binding region of an antibody is formed by the

A) variable region composed of a heavy chain and a light chain.
B) variable region composed of two heavy chains.
C) variable region composed of two light chains.
D) constant region composed of a heavy chain and a light chain.
E) constant region composed of two light chains.

Question 27

Natural killer cells can kill infected or abnormal cells by the release of in the target cell's membrane.

A) perforins
B) complement proteins
C) interferons
D) antibodies
E) fragmentins

Question 28

Each antibody can bind

A) two epitopes of the same kind.
B) three epitopes of the same kind.
C) two epitopes of one kind and one epitope of a different kind.
D) one epitope only.
E) two different types of epitopes.

Question 29

In the end, the complement system destroys invading bacteria by , which form pores

A) forming a membrane attack complex, which causes the cell to fill with fluid and lyse.
B) agglutination.
C) release of lytic enzymes.
D) neutralization.
E) phagocytosis.

Question 30

The complement cascade can be activated by binding to

A) natural killer cells only.
B) antibodies attached to bacterial cells only.
C) carbohydrates present on bacterial cells only.
D) either carbohydrates or antibodies on bacterial cells.
E) either natural killer cells or carbohydrates on bacterial cells.

Question 31

Compared to humoral immunity, cell -mediated immunity is more likely to defend against which of the following?

A) virally infected cells only
B) transplanted tissue only
C) cancer cells only
D) both virally -infected cells and cancer cells
E) virally -infected cells, cancer cells, and transplanted tissue

Question 32

What is/are a component of the complement system that coats the bacterial surface, acting as an opsonin to enhance phagocytosis of bacteria?

A) C3b
B) CD8
C) polysaccharides
D) CD4
E) C2c

Question 33

If bacteria are exposed to a B cell in the spleen, they will initiate a(n)

A) response from the complement system.
B) humoral immune response.
C) nonspecific immune response.
D) inflammatory response.
E) cell -mediated immune response.

Question 34

The pathway is important in early nonspecific responses to infection because it occurs in the absence of antibodies.

A) clonal selection
B) classic
C) humoral
D) cell -mediated
E) alternative

Question 35

The process of clonal selection gives rise to short -lived clones called antigen that stimulated their production.

A) memory cells
B) helper cells
C) effector cells
D) antigens
E) antibodies

Question 36

Why is a secondary immune response stronger?

A) Exposure to a previously encountered antigen gives rise not only to effector cells but also to clones of long -lived memory T cells and memory B cells.
B) Antibodies produced during the primary response are still present circulating in the blood.
C) Body cells develop resistance to the pathogen.
D) Body cells are primed to produce antibodies against the pathogen.
E) Effector cells produced during the primary response are still present circulating in the blood.

Question 37

In order to mount a response, particular B or T cells must express the appropriate that will bind to the _.

A) antigenic determinant : antigen
B) antigen : antigen receptor
C) epitope : antigen
D) antigen : antibody
E) antigen receptor : antigen

Question 38

Which of the following is NOT one of the important properties of the immune system that results from the action of B and T cells?

A) memory
B) specificity
C) self -tolerance
D) diversity
E) redundancy

Question 39

Which statement best describes why an individual's antibodies and T cells do not attack their own cells?

A) B and T cells mature in the bone marrow and thymus; their antigen receptors are, in effect, tested for their potential to recognize and react against self.
B) Opsonins keep leukocytes from binding to the B and T cells
C) B and T cells develop into plasma cells which dissolve automatically into the plasma, thus they are not recognized as foreign.
D) Interferons interfere with antibodies trying to attach to the B and T cells
E) B and T cells have about 100,000 antigen receptors and so they can match anything in the human body.

Question 40

Interferons a and fi are released from

A) T lymphocytes : degrading RNA
B) phagocytotic cells : digesting the virus
C) infected cells : degrading RNA
D) neutrophils : digesting the virus
E) phagocytotic cells : degrading RNA

Question 41

The protein on the cytotoxic T cell binds to the
Major histocompatibility (MHC)
Molecule on the infected cell.

A) CD4 : class II
B) CD8 : class II
C) CD8 : class I
D) CD6 : class I
E) CD4 : class I

Question 42

The development of memory B cells in response to an antigen requires the secretion of from cells.

A) interleukin -2 : helper T cells
B) tumor necrosis factor -a : natural killer cells
C) interleukin -2 : cytotoxic T cells
D) interleukin -6 : helper T cells
E) interferon -y : cytotoxic T cells

Question 43

Once bound by antibodies, an antigen is effectively opsonized and thus rendered more

A) likely to agglutinate.
B) likely to block the activity of a pathogen.
C) to be recognized by natural killer cells.
D) to the complement cascade.
E) susceptible to phagocytosis.

Question 44

Which statement best describes the mechanism of neutralization?

A) Pathogens are bound by antibodies and are more susceptible to phagocytosis.
B) Cells are neutralized by toxins injected by natural killer cells.
C) It causes pathogenic cells to lyse.
D) Antigens clump together and are more susceptible to phagocytosis.
E) An antibody blocks an antigen's activity by binding to it.

Question 45

While some of the daughter helper T cells are secreting the appropriate interleukins, others form into cells.

A) suppressor T
B) cytotoxic T
C) memory B
D) memory T
E) plasma

Question 46

What secretes cytokines that enhance the activity of B cells, cytotoxic T cells, suppressor T cells, and helper T cells?

A) B cells
B) macrophages
C) helper T cells
D) suppressor T cells
E) cytotoxic T cells

Question 47

What cells are also called CD4 cells?

A) helper T cells
B) cytotoxic T cells
C) suppressor T cells
D) plasma cells
E) B cells

Question 48

Polysaccharides on bacterial cells stimulate the production of antibodies by binding to

A) B cells that release interleukin -2 to stimulate plasma cell proliferation.
B) B cells that stimulate plasma cell proliferation.
C) helper T cells that release interleukin -1 to stimulate plasma cell proliferation.
D) B cells that stimulate plasma and memory cell proliferation.
E) helper T cells that directly stimulate plasma and memory cell proliferation.

Question 49

Activation of cytotoxic T cells requires binding to class I MHC molecule complexed with a foreign antigen and the release of

A) interleukin -2 : helper T cells
B) interleukin -10 : macrophages
C) interleukin -1 : helper T cells
D) interleukin -1 : macrophages
E) interleukin -2 : macrophages

Question 50

Cells that leave the thymus with the ability to bind to class I major histocompatibility (MHC) molecules will develop into

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

Question 51

In humans, the major histocompatibility (MHC) molecule is known as the

A) human leukocyte antibody.
B) human lymphoid tissue.
C) human lymphoid antibody.
D) human leukocyte antigen.
E) human leukocyte association.

Question 52

In order to be detected by a T cell, the class I major histocompatibility (MHC) molecule of infected cells must go through the process of

A) antibody binding.
B) antigen presentation.
C) phagocytosis.
D) perforin incorporation.
E) complement activation.

Question 53

In the process of agglutination, IgD antibodies

A) stimulate the release of histamine from mast cells.
B) remove the antigen from the pathogen.
C) block access to the antigenic site.
D) activate the complement system.
E) bind to antigens on two different cells.

Question 54

Receptors on every T cell detect foreign antigens on cells of the body by their association with the on the surface of the infected cells of the body.

A) major histocompatibility (MHC) molecule
B) CD4
C) antibodies
D) CD8
E) membrane attack complex

Question 55

Activation of helper T cell proliferation, once it has bound to its major histocompatibility (MHC) molecule, involves the release of

A) interleukin -10 : macrophages
B) interleukin -2 : B cells
C) interleukin -1 : B cells
D) interleukin -4 : cytotoxic T cells
E) interleukin -2 : macrophages

Question 56

Which of the antibody classes is able to destroy an antigen by activating the nonspecific killing action of the natural killer cells?

A) IgM only
B) IgG only
C) IgE only
D) both IgG and IgM
E) both IgM and IgE

Question 57

Which of the antibody classes is able to cross epithelial cells and is therefore present in breast milk?

A) IgA only
B) IgM only
C) IgG only
D) both IgG and IgM
E) both IgM and IgA

Question 58

A plasma cell secretes approximately days.

A) 10,000 : 4 -7
B) 2000 : 4 -7
C) 10,000 : 7 -10
D) 2000 : 10 -20
E) 2000 : 7 -10

Question 59

Cells that leave the thymus with the ability to bind to class II major histocompatibility (MHC) molecules will develop into

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

Question 60

In order to be detected by a T cell, the class II major histocompatibility (MHC) molecule of infected cells must go through the process of

A) antibody binding
B) phagocytosis
C) perforin incorporation
D) complement activation
E) MHC molecule presentation

Question 61

Hay fever that occurs when people are exposed to pollen involves an excess release of IgE, which binds to _ and causes them to .

A) pollen : stimulate the release of histamine
B) T helper cells : stimulate the proliferation of cytotoxic T cells
C) mast cells : stimulate the proliferation of cytotoxic T cells
D) macrophages : destroy the pollen whose by -products stimulate histamine release
E) mast cells : degranulate, releasing histamine

Question 62

Blood is classified into different types based on the presence or absence of certain surface of a person's red blood cells.

A) IL -2 molecules
B) antibodies
C) MHC molecules
D) antigens
E) HLA molecules

Question 63

Diabetes mellitus can be caused by a form of autoimmune disease that attacks

A) alpha cells of the pancreas, which destroys insulin production.
B) insulin receptors, preventing insulin from acting on cells.
C) the exocrine portion of the pancreas.
D) beta cells of the pancreas, which destroys insulin production.
E) GLUT4 proteins as they insert into the membrane.

Question 64

Vaccines are composed of that stimulate an active immunity to the pathogen.

A) memory T cells that respond to a microorganism
B) the non -pathogenic portion of the microorganism
C) the pathogenic portion of the microorganism
D) antibodies to a microorganism
E) memory B cells that respond to a microorganism

Question 65

Which statement best describes the difference between passive immunity and active immunity?

A) Active immunity depends on injecting antibodies into the body whereas passive immunity includes vaccination or immunization of a safe form of a pathogen.
B) Active immunity refers to T lymphocytes actively destroying pathogens through phagocytosis and passive immunity describes the indirect attack by B lymphocytes through secretion of antibodies.
C) Active immunity depends on the ability of a person's immune system to mount a response to a pathogen and induces immunological memory, whereas in passive immunity only antibodies are introduced to the body allowing only for short -term protection.
D) Active immunity is only active for a short time frame in the body whereas passive immunity has long -lasting immunity in the body.
E) Active immunity fight viruses such as rabies by injecting antibodies collected from that animal whereas passive immunity is injecting antibodies from a safe form of the pathogen.

Question 66

Which statement best describes why packed red blood cells are usually transfused instead of whole blood?

A) Whole blood contains plasma proteins that could cause edema in the patient.
B) Packed red blood cells provide the red blood cells the recipient needs without adding plasma that may change their fluid volume too much.
C) Packed red blood cells are smaller than whole blood cells and therefore enter the bloodstream faster than whole blood.
D) Whole blood contains antibodies that could attack the recipient's antigens on their red blood cells.
E) Whole blood is diluted with plasma so the recipient might not receive the needed number of red blood cells.

Question 67

What antibody is most involved in the allergic response?

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

Question 68

People who have type AB blood are considered

A) universal recipients : have antibodies to A and B
B) universal recipients : have no antibodies to A or B
C) universalists : cannot receive blood transfusions
D) universal donors : have no antibodies to A and B
E) universal donors : have antibodies to A and B

Question 69

The incorporation of perforins into the cell membrane results in the cell's

A) binding of the helper T cell.
B) being marked for degradation by macrophages.
C) being bound by antibodies.
D) shrinkage and subsequent death.
E) swelling and subsequent lysis.

Question 70

A number of tumors and viruses (e.g., Epstein -Barr) are able to escape cytotoxic T cell degradation by inhibiting what?

A) the production of the class I MHC molecule
B) the production of the class II major histocompatibility (MHC) molecule
C) the activation of the complement system
D) helper T cell activation
E) tumor antigen expression

Question 71

The most acute allergic response is anaphylactic shock, which can be deadly due to the histamine -induced

A) increase in peripheral resistance that decreases cardiac output.
B) increase in capillary permeability.
C) decrease in peripheral resistance that decreases mean arterial pressure.
D) local decrease in resistance with little effect on mean arterial pressure.
E) decrease in peripheral resistance that increases cardiac output.

Question 72

Cytotoxic T cells release two proteins to destroy infected cells: , which forms pores in the membrane of the infected cells, and and triggers apoptosis.

A) MHC class I : MHC class II
B) perforins : fragmentins
C) fragmentins : perforins , which enters the infected cell through these pores
D) complement system proteins : perforins
E) complement system proteins : fragmentins

Question 73

People who have type O blood are considered _

A) universalists : cannot receive blood transfusions
B) universal recipients : have no antibodies to A or B
C) universal donors : have no A or B antigens
D) universal recipients : have no A or B antigens
E) universal donors : have no antibodies to A or B

Question 74

Type A blood could donate to which of the following blood types?

A) A and O
B) A and AB
C) A, AB, and O
D) B only
E) A only

Question 75

The primary mechanism whereby cytotoxic T cells are able to destroy infected cells involves

A) enzymatic degradation.
B) incorporation of the major attack complex.
C) activation of the complement system.
D) phagocytosis.
E) the incorporation of perforins into the cell membrane.

Question 76

A natural form of passive immunity involves the transfer of

A) IgG antibodies to an infant through the mother's milk.
B) IgE antibodies by sneezing.
C) IgA antibodies across the placenta.
D) IgA antibodies to an infant through the mother's milk.
E) IgG antibodies by kissing.

Question 77

Tissue transplantation has been made possible by our ability to

A) inhibit interleukin -5.
B) closely match HLA molecules between individuals.
C) alter the expression of the HLA molecules.
D) competitively inhibit HLA molecules.
E) inhibit the binding of helper T cells to the HLA.

Question 78

What hormone, released in times of stress, directly inhibits the function of the immune system?

A) aldosterone
B) corticosteroid
C) epinephrine
D) ADH
E) glucagon

Question 79

Which of the following cells are activated by the release of interleukin -10 from the helper T cells?

A) natural killer cells
B) mast cells
C) macrophages
D) B cells
E) cytotoxic T cells

Question 80

What phagocyte initiates inflammation?

A) cytotoxic T cells
B) natural killer cells
C) mast cells
D) helper T cells
E) macrophages