Deck 18: The Immune System

Question 1

The killing of cancerous cells by the immune system is called:

A) immune oversight.
B) immune surveillance.
C) tissue immunity.
D) phagocytosis.
E) hemostasis.

Answer 1

B

Question 2

Colony-stimulating factors are produced by ________________ and target cells in the _____________________, which results in _______________.

A) macrophages; bone marrow; stimulation of proliferation of neutrophils and monocytes
B) B cells; thymus; conversion of B cells to T cells
C) NK cells; blood vessel walls; vasodilation
D) monocytes; blood vessel walls; vasoconstriction
E) basophils; bone marrow; release of histamine

Answer 2

A

Question 3

Which of the following statements regarding phagocytosis is TRUE?

A) Macrophages are the only phagocytes in the tissues.
B) The microbe engulfed by the phagocyte is killed by lysosomal enzymes and hydrogen peroxide.
C) Phagocytosis is controlled by a negative feedback mechanism whereby phagocytes release chemicals that inhibit further phagocytosis.
D) The microbe engulfed by the phagocyte is killed by the membrane attack complex (MAC).
E) Antibodies found inside lysosomes attack and kill microbes that are engulfed by phagocytosis.

Answer 3

B

Question 4

Which is TRUE regarding the immune system cells?

A) Plasma cells are derived from T cells.
B) Macrophages are derived from basophils.
C) Macrophages are derived from monocytes.
D) The immune cells found within the bloodstream are called erythrocytes.
E) Neutrophils are classified as lymphoid cells.

Question 5

Which of the following statements regarding complement is FALSE?

A) Certain complement proteins are always circulating in the blood in an inactive state.
B) Activated complement can form a membrane attack complex, which forms pores in microbe membranes.
C) Activated complement can stimulate cells to secrete inflammation-mediating chemicals.
D) The complement pathway is always dependent upon activation of the first complement protein, C1.
E) Some activated complement proteins activate other complement proteins.

Question 6

Helper T cells:

A) are activated by antigen presented with MHC II proteins.
B) secrete antibodies that target specific antigens.
C) secrete perforin when activated.
D) convert to plasma cells after they are activated.
E) do not interact with MHC proteins.

Question 7

Which of the following statements about the immune system is TRUE?

A) Neutrophils, basophils, eosinophils, and monocytes originate in bone marrow.
B) Natural killer cells produce specific antibodies that kill bacteria and viruses.
C) Mast cells are derived from monocytes.
D) Plasma cells are derived from T lymphocytes.
E) Macrophages are derived from neutrophils.

Question 8

The immune system destroys or neutralizes:

A) bacteria.
B) viruses.
C) nonmicrobial foreign substances.
D) cancer cells that arise in the body.
E) All of the choices are correct.

Question 9

Which applies to the classical complement pathway, but NOT to the alternative complement pathway?

A) Activation of C3 results in the formation of C3b.
B) There is a cascade of proteins activated, which results in the killing of microbes.
C) Complement proteins serve as opsonins that facilitate phagocyte binding to microbes.
D) Antibodies activate the first complement protein (C1).
E) Complement activation leads to the development of a multiunit protein called the membrane attack complex (MAC).

Question 10

Which is NOT true about viruses?

A) They consist of a nucleic acid surrounded by a carbohydrate shell.
B) They require a host cell in order to reproduce themselves.
C) They may reside in a host cell for years without killing it.
D) They may cause a host cell to become cancerous.
E) They may have genetic information in the form of RNA.

Question 11

Which of the following statements regarding the lymphoid organs is NOT true?

A) The primary lymphoid organs are the bone marrow and thymus.
B) The thymus secretes protein hormones, collectively called thymopoietins.
C) Large numbers of macrophages and lymphocytes are found in the lymph nodes and spleen.
D) The tonsils contain lymphocytes, macrophages, and dendritic cells that respond to microbes in food.
E) Once a lymphocyte reaches a secondary lymphoid organ, it remains there for its lifetime.

Question 12

After initial entry of bacteria into a cut in the skin, vasodilation of local blood vessels and increased capillary permeability occur. Which of the following events is NOT part of the adaptive immune response to the infection?

A) antigen interaction with lymphocytes
B) production of antibodies that bind to antigens
C) B-cell differentiation into plasma cells
D) vasodilation of local blood vessels
E) activation of lymphocytes

Question 13

Which does NOT accurately describe interferons?

A) They are proteins produced by most cells of the body in response to infection by a virus.
B) They interfere with viral replication in cells.
C) They play a role in the killing of tumor cells.
D) They kill bacteria by forming pores in the cell membrane.
E) They bind to surface receptors on cells, and trigger cellular production of antiviral proteins.

Question 14

Cells of the immune system capable of phagocytosis include:

A) macrophages, NK cells, and basophils.
B) B cells, T cells, and macrophages.
C) monocytes, neutrophils, and plasma cells.
D) macrophages, neutrophils, and dendritic cells.
E) macrophages, mast cells, and lymphocytes.

Question 15

Chemotaxis:

A) refers to the chemical attraction of neutrophils to a site of inflammation.
B) is important only for innate immune responses.
C) is important only for adaptive immune responses.
D) refers to the engulfing of microbes and foreign molecules by macrophages.
E) refers to dilation of blood vessels by chemicals released by damaged tissue cells.

Question 16

Which of the following statements regarding the chemical mediators of inflammatory responses is NOT true?

A) They may be secreted by cells residing in the area of injury.
B) They may be secreted by cells that enter the affected area.
C) They may be generated by enzymatic cleavage of proteins in plasma.
D) They are all peptides.
E) They may be chemotaxins.

Question 17

Which of the following statements regarding phagocytes and phagocytosis is true?

A) Macrophages, monocytes, and mast cells are phagocytes.
B) Contact of phagocytes with microbes stimulates the phagocytes to release chemicals that mediate the inflammatory response.
C) Phagocytosis is stimulated by the presence of proteins called rhodopsins.
D) Phagocytosis is the process by which leukocytes exit the bloodstream.
E) Phagocytosis is a process that only occurs within the bloodstream.

Question 18

Which of the following cell types binds to antigens on plasma membranes of target cells and directly destroys the cells?

A) neutrophils
B) NK cells
C) cytotoxic T cells (CD8 cells)
D) helper T cells (CD4 cells)
E) B cells

Question 19

After activation of C3 of the complement system, which of these is a role of its component part, C3b?

A) It acts as an enzyme to convert nitric oxide into hydrogen peroxide.
B) It causes vasodilation of local blood vessels.
C) It acts as a chemotaxin for macrophages.
D) It stimulates the conversion of monocytes to neutrophils.
E) It acts as an opsonin that is recognized by phagocytes targeting the microbe for destruction.

Question 20

Which of the following statements regarding major histocompatibility proteins (MHCs) is TRUE?

A) Class I MHCs are found on all cells of the body except erythrocytes.
B) Class II MHCs are normally found in the cell membranes of bacteria.
C) Cytotoxic T cells require class II MHCs to recognize foreign antigens.
D) All humans have identical sets of MHC proteins.
E) MHC proteins are the same thing as antibodies.

Question 21

What two cell types are mainly responsible for graft rejection?

A) B cells and helper T cells
B) natural killer cells and B cells
C) marcrophages and natural killer cells
D) cytotoxic T cells and helper T cells
E) B cells and plasma cells

Question 22

Which of the following statements regarding blood-type incompatibilities between a mother and her fetus is TRUE?

A) An Rh-negative fetus may be at risk if its mother is Rh-positive.
B) An Rh-positive fetus may be at risk if its mother is Rh-negative.
C) A fetus with type B blood may be at risk if its mother has type O blood.
D) The risk to an Rh-positive fetus of an Rh-negative mother is lessened if she has previously carried an Rh-negative fetus.
E) The greatest risk to a fetus occurs when both mother and fetus are Rh-positive.

Question 23

Antibodies are:

A) secreted by helper T cells.
B) cytokines.
C) immunoglobulins.
D) composed of two polypeptide chains - a heavy chain and a light chain.
E) phagocytes.

Question 24

Natural killer cells:

A) are activated by IL-2 and interferon-gamma.
B) only attack bacteria.
C) cannot interact with antibodies.
D) secrete interferon-gamma to activate helper T-cells.
E) have primary responsibility for mass-manufacturing antibodies against foreign antigens.

Question 25

Which is NOT an example of an autoimmune disease?

A) AIDS
B) multiple sclerosis
C) myasthenia gravis
D) rheumatoid arthritis
E) type 1 diabetes mellitus

Question 26

Which of these correctly describes a systemic response to infection?

A) Appetite generally increases compared to normal.
B) The body's set point temperature is reset so that body temperature is maintained lower than normal.
C) The liver retains iron and zinc so plasma levels are decreased from normal.
D) There is reduced breakdown of triglycerides in adiopse tissue and a decrease in plasma free fatty acids compared to normal.
E) Secretion of cortisol by the adrenal cortex is decreased.

Question 27

Which type of allergy/hypersensitivity occurs independent of antibodies?

A) immune-complex hypersensitivity
B) immediate hypersensitivity
C) cytotoxic hypersensitivity
D) delayed hypersensitivity

Question 28

After phagocytosis of a microbe, vesicles called phagosomes combine with intracellular organelles called ________________, resulting in destruction of the microbe.

A) autosomes
B) ribosomes
C) nucleosomes
D) mitochondria
E) lysosomes

Question 29

Which is NOT true about AIDS?

A) It is caused by a retrovirus.
B) It is caused by a virus that contains RNA.
C) It is transmitted by intimate contact with infected blood, sexual intercourse with an infected partner, or by an infected mother to her fetus or breast-fed infant.
D) Certain unusual cancers such as Kaposi's sarcoma co-occur with relatively high frequency.
E) The HIV virus preferentially enters and disables B cells.

Question 30

Individuals who have been infected by the human immunodeficiency virus (HIV):

A) always manifest symptoms early in the disease process.
B) can be diagnosed only when they develop certain rare forms of cancer.
C) succumb to the disease in a relatively brief period of time after infection due to massive loss of T lymphocytes.
D) generally are diagnosed by detection of anti-HIV antibodies or HIV RNA in their blood.
E) have normal B-cell and cytotoxic T-cell function.

Question 31

Which class of antibodies are commonly called gamma globulin?

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

Question 32

When an antigen is bound to an antibody, it binds to:

A) the heavy immunoglobulin chain only.
B) the light immunoglobulin chain only.
C) a specific antigen-binding site formed by heavy and light chains.
D) a hypervariable region of immunoglobulin DNA.
E) gamma immunoglobulin only.

Question 33

Which of the following statements regarding the secretions of immune system cells is TRUE?

A) Type 2 interferons are only secreted by macrophages.
B) Interleukin 2 is a cytokine secreted by most immune cells.
C) Type 1 interferons are also called interferon-gamma.
D) Colony-stimulating factors are secreted mainly by plasma cells.
E) Antibodies are produced and secreted by macrophages.

Question 34

Which is NOT a function performed by activated macrophages?

A) They perform phagocytosis.
B) They secrete cell-killing chemicals.
C) They present antigens to T-cells.
D) They secrete cytokines involved in inflammation.
E) They produce antibodies that bind to specific antigens.

Question 35

B cells that differentiate during an initial immune response but remain dormant until being activated during a subsequent exposure to an antigen are called:

A) T cells.
B) memory cells.
C) macrophages.
D) monocytes.
E) cytokines.

Question 36

Which of the following is NOT normally a route of transmission of HIV/AIDS?

A) unprotected sexual intercourse with an infected partner
B) kissing or contact with items contaminated by the saliva of an infected individual
C) across the placenta from an infected mother to her fetus during pregnancy or delivery
D) via breast milk during nursing
E) transfer of contaminated blood or blood products from one person to another

Question 37

Which of the following is NOT a systemic effect of IL-1 and other cytokines in response to infection or tissue injury?

A) increased plasma levels of amino acids
B) increased secretion of colony-stimulating factors
C) decreased appetite
D) secretion of acute-phase proteins by the liver
E) stimulation of helper T cells

Question 38

Cytotoxic T cells:

A) secrete perforin, which kills bacteria and viruses by perforating the membrane or coat that surrounds them.
B) are activated by interleukin 1.
C) require Class I MHC proteins to recognize foreign antigens.
D) are converted to plasma cells when activated by MHC proteins.
E) secrete proteins that neutralize bacterial toxins.

Question 39

Which is normally present in a subject with type O blood?

A) erythrocytes carrying type A antigen
B) erythrocytes carrying type B antigen
C) both anti-A and anti-B antibodies in the plasma
D) erythrocytes with both type A antigen and type B antigen
E) plasma that has neither anti-A nor anti-B antibodies

Question 40

Which is NOT true regarding antibodies?

A) They are secreted by plasma cells.
B) They protect against viruses by binding to them and presenting them to phagocytes.
C) They protect against viruses by binding to them and neutralizing them.
D) They activate complement.
E) They are the main mediators of the innate immune response.

Question 41

Antibody-mediated responses and humoral responses are two different categories of adaptive immune responses.

Question 42

Immune surveillance refers to the search for and destruction of bacteria in the blood.

Question 43

Helper T cells bind to antigen complexed with class II MHC proteins, while cytotoxic T cells bind to antigen complexed with class I MHC proteins.

Question 44

In cell-mediated immune responses, immune cells directly kill antigen-bearing cells.

Question 45

A person who receives a vaccine made from killed virus particles will, if the vaccination is successful, acquire passive immunity against that virus.

Question 46

The body's first line of defense against invasion by microbes is a physical and chemical barrier.

Question 47

Unlike cytotoxic T cells, natural killer cells do not require antigen to be complexed with class I MHC proteins in order to bind to the antigen.

Question 48

Histamine is a mediator of inflammatory responses that is generated by enzymatic cleavage of a plasma precursor.

Question 49

HIV preferentially attacks cytotoxic T cells.

Question 50

Adaptive immune responses differ from innate immune responses in that the former are mediated by lymphocytes.

Question 51

A chemical that causes binding of a phagocyte to a microbe is called a chemotaxin.

Question 52

A consequence of inflammation is increased capillary filtration and edema, which causes swelling and pain.

Question 53

The primary difference between active and passive immunity is that in active immunity, antibodies are produced in response to the presence of an antigen, while in passive immunity, pre-formed antibodies are provided from one person to another.

Question 54

Cytotoxic T cells kill body cells by phagocytosis.

Question 55

Bone marrow is the primary site of B lymphocyte maturation.

Question 56

Helper T cells are important only for cell-mediated immune responses.

Question 57

The local response to injury in the body is called infection.

Question 58

T lymphocytes mature primarily in the thymus.

Question 59

The rationale behind the drugs used to treat HIV/AIDS is to reduce the number of viruses present in the body to infect otherwise healthy cells. Which of these is NOT a therapy that acts in this way?

A) inhibition of the reverse transcriptase enzyme
B) interference with the processes involved in expression of viral nucleic acid by the host cell
C) blocking an alpha protease enzyme associated with the assembly of the virus
D) chemical agents directed at interruption of mitosis in host cells for the virus
E) blocking the attachment and fusion of the HIV viruses with T lymphocyte host cells

Question 60

A phagocyte can kill a microbe only after phagocytosis.

Question 61

Drugs that block the production of cytokines, like cyclosporin, may be useful for treating autoimmune disorders.

Question 62

People lacking Rh factor are born with circulating antibodies against it.

Question 63

Treatment of individuals with HIV infection focuses upon early detection by interfering with the processes involved in replication and assembly of the virus by T lymphocytes, rather than attacking infected host cells directly.

Question 64

The appearance of the signs and symptoms of AIDS in an HIV-infected individual generally appear after the virus has had enough time to replicate within host tissue cells and to cause death and destruction of cells critical to mounting a normal immune response.

Question 65

A patient with AIDS would be likely to react to an infection with a greater elevation of plasma cortisol than a person without the disease.

Question 66

The skin constitutes a good barrier for foreign chemicals that are nonpolar.

Question 67

Passive immunization of an Rh-negative woman with anti-Rh factor antibodies within a few hours of giving birth to an Rh-positive baby is helpful in preventing hemolytic disease of the newborn in a subsequent pregnancy.

Question 68

A person with type B blood can generally accept a transfusion of type AB blood.