Deck 48: The Immune System in Animals

Question 1

Mutant fruit flies that do not make Toll protein were tested for survival after fungal infection. The results shown in the accompanying graph support the hypothesis that ________.

A) Toll protein is necessary for protection from death by fungal infection
B) after fungal infection, wild-type flies die more rapidly than mutants lacking the Toll protein
C) flies lacking the Toll protein die within one day of a fungal infection
D) Toll proteins have a delayed affect in killing flies

Answer 1

A

Question 2

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
Inflammatory responses typically include ________.

A) clotting proteins migrating away from the site of infection
B) increased activity of phagocytes in an inflamed area
C) reduced permeability of blood vessels to conserve plasma
D) release of substances to decrease the blood supply to an inflamed area
E) inhibiting the release of white blood cells from bone marrow

Answer 2

B

Question 3

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
A fruit fly, internally infected by a potentially pathogenic fungus, is protected by its ________.

A) plasma cells
B) immunoglobulins
C) antibodies
D) Toll proteins
E) B cells

Answer 3

D

Question 4

What type of immunoglobulin is the most associated with breast feeding?

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

Question 5

Antigens are ________.

A) proteins found in the blood that cause foreign blood cells to clump
B) proteins embedded in B-cell membranes
C) proteins that consist of two light and two heavy polypeptide chains
D) foreign molecules that trigger an immune response
E) proteins released during an inflammatory response

Question 6

The immune response that is rapid but generic is called ________.

A) acquired immune response
B) adaptive immune response
C) individual immune response
D) innate immune response

Question 7

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
Innate immunity ________.

A) is activated immediately upon infection
B) depends on an infected animal's previous exposure to the same pathogen
C) is based on recognition of antigens that are specific to different pathogens
D) is found only in vertebrate animals
E) utilizes highly specific antigen receptors on B cells

Question 8

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
An inflammation-causing signal released by mast cells at the site of an infection is ________.

A) an interferon
B) lymphatic fluid
C) histamine
D) mucus
E) sodium ions

Question 9

How does the immune system of vertebrates utilize a chemical concentration gradient?

A) The immune system produces thousands of histamines that act solely to create a histamine diffusion barrier.
B) The immune system generates a gradient of reactive oxygen intermediates to increase the amount of toxic radicals and peroxides to combat invading pathogens.
C) The immune system releases chemical signals called chemokines, which create a chemical gradient that leukocytes use in migrating toward the infection site.
D) The vertebrate immune system does not use chemical gradients.

Question 10

What major advantage is conveyed by having a system of adaptive immunity?

A) It enables a rapid defense against an antigen that has been previously encountered.
B) It enables an animal to counter most pathogens almost instantly the first time they are encountered.
C) It results in effector cells, each of which has specificity for a large number of antigens.
D) It allows for the destruction of antibodies.

Question 11

What kind of immune responses do insects have?

A) innate immunity only
B) innate and adaptive immunity
C) adaptive immunity only
D) They have innate and adaptive immunity, but the adaptive immune system has fewer cells than that of vertebrates.

Question 12

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
The cells and signaling molecules involved in the initial stages of the inflammatory response are ________.

A) phagocytes and lysozymes
B) macrophages and chemokines
C) dendritic cells and interferons
D) mast cells and histamines
E) lymphocytes and interferons

Question 13

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
Phagocytic cells of innate immunity of vertebrates include ________.
I) neutrophils
II) macrophages
III) platelets
IV) mast cells

A) I and II
B) II and IV
C) I and IV
D) I, II, and III
E) I, II, III, and IV

Question 14

A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. What response is occurring?

A) inflammatory response
B) lytic response
C) adaptive immune response
D) autoimmune response

Question 15

If you were developing artificial B-cell receptors (BCRs) based on the natural version and wanted to change the BCRs' ability to bind certain antigens, which region of the natural receptor would you alter?

A) transmembrane domain
B) the V and J regions of the light-chain and heavy-chain components of the BCR immunoglobulin
C) the C region of the light-chain and heavy-chain components of the BCR immunoglobulin
D) the region projecting into the cytosol of the cell

Question 16

An epitope is ________.

A) part of the interferon molecule that penetrates foreign cells
B) a protein protruding from the surface of B cells
C) two structurally similar antibodies dissolved in the blood plasma
D) the part of an antigen that actually binds to an antibody, BCR or TCR
E) a mirror image of an antigen

Question 17

Lymphocytes mature in the ________.
I) spleen
II) thymus
III) bone marrow

A) only I and III
B) only I and II
C) only II and III
D) I, II, and III

Question 18

Adaptive immunity is based upon ________.

A) traits common to groups of pathogens
B) antigen-specific recognition
C) maternal provision of antibodies to offspring
D) plants being exposed to new pathogens
E) having exhausted all options for innate immunity responses

Question 19

Antigens are ________.

A) immunoglobulins
B) used by the immune system to neutralize foreign objects
C) foreign molecules that can initiate an immune response
D) produced by white blood cells

Question 20

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters.
The most inclusive set of symptoms of inflammation is ________.

A) heat, pain, and redness
B) pain and whitening of the surrounding tissue
C) swelling and pain
D) antibody-producing cells
E) swelling, heat, redness, and pain

Question 21

Differences in the B-cell receptors of two different B cells are due to ________.

A) mutation in the genes of that B cell, induced by exposure to the antigen
B) the rearrangement of C-region genes in that clone of responsive B cells
C) a switch in the kind of antigen-presenting cell that is involved in the immune response
D) a patient's reaction to the first kind of antibody made by the plasma cells
E) the recombination of variable regions of the light-chain and heavy-chain genes

Question 22

Which of the following statements are fundamental to the clonal-selection theory of how the adaptive immune system functions?
I) Each mature lymphocyte has a unique membrane receptor that recognizes one antigen.
II) When the lymphocyte binds an antigen, the lymphocyte is activated and begins dividing to form many identical copies of itself.
III) Cloned lymphocytes have slight differences and are selected by the spleen for removal if they do not bind an antigen.
IV) Cloned cells descend from an activated lymphocyte and persist even after the pathogen is eliminated.

A) only I and III
B) only II and IV
C) only I, II, and IV
D) only II, III, and IV
E) I, II, III, and IV

Question 23

An immunoglobulin molecule has a light chain made up of ________.

A) one C region, one J region, and two V regions
B) one C region, two J regions, and one V region
C) one D region, one J region, and one V region
D) one C region, one J region, and one V region
E) one C region, one D region, and one J region

Question 24

Among the last line of defenses against prolonged exposure to an extracellular pathogen is ________.

A) lysozyme production
B) phagocytosis by neutrophils
C) antibody production by plasma cells
D) histamine release by basophils
E) mast cell activation

Question 25

Arrange in the correct sequence these components of the mammalian immune system as it first responds to a pathogen.
I) Pathogen is destroyed.
II) Lymphocytes secrete antibodies.
III) Antigens from the pathogen bind to receptors on lymphocytes.
IV) Lymphocytes specific to antigens from the pathogen become numerous.
V) Only memory cells remain.

A) I → III → II → IV → V
B) III → II → I → V → IV
C) II → I → IV → III → V
D) IV → II → III → I → V
E) III → IV → II → I → V

Question 26

Clonal selection implies that ________.

A) brothers and sisters have similar immune responses
B) specific lymphocytes divide mitotically when activated by an antigen
C) only certain cells can produce interferon
D) a B cell has multiple types of antigen receptors
E) the body selects which antigens it will respond to

Question 27

Antibodies of the different classes IgM, IgG, IgA, IgD, and IgE differ from each other ________.

A) in the way they are produced
B) in their heavy-chain structure
C) in the type of cell that produces them
D) by the antigenic determinants that they recognize

Question 28

The activation of helper T cells is likely ________.

A) when an antigen is displayed by a dendritic cell
B) when a cytotoxic T cell releases cytokines
C) when natural killer cells come in contact with a tumor cell
D) in the bone marrow during the self-tolerance test
E) when B cells respond to T-independent antigens

Question 29

An epitope associates with which part of an antibody?

A) the disulfide bridge
B) the heavy-chain constant regions only
C) variable regions of a heavy chain and light chain combined
D) the light-chain constant regions only
E) the tail

Question 30

T cells of the immune system include ________.

A) CD4, CD8, and plasma cells
B) cytotoxic and helper cells
C) plasma, antigen-presenting, and memory cells
D) lymphocytes, macrophages, and dendritic cells
E) class I MHC, class II MHC, and memory cells

Question 31

Clonal selection and differentiation of B cells activated by antigen exposure leads to the production of ________.

A) large numbers of neutrophils
B) large quantities of the antigen initially recognized
C) vast numbers of B cells with random antigen-recognition receptors
D) erythrocytes that can later secrete antibodies for the antigen
E) plasma cells that secrete antibodies for the antigen

Question 32

Which statement best describes the difference in responses of effector B cells (or plasma cells) and cytotoxic T cells?

A) Effector B cells confer active immunity; cytotoxic T cells confer passive immunity.
B) Effector B cells kill pathogens directly; cytotoxic T cells kill host cells.
C) Effector B cells secrete antibodies that are specific for a certain pathogen; cytotoxic T cells kill pathogen-infected host cells.
D) Effector B cells carry out the cell-mediated response; cytotoxic T cells carry out the humoral response.
E) Effector B cells respond only the first time a pathogen is present; cytotoxic T cells respond subsequent times.

Question 33

B-cell receptors bind to antigens that are either freely dissolved or present on the surface of invading or foreign cells. T-cell receptors ________.

A) are active only in lymph nodes
B) bind only to antigens present on the surface of the invading or foreign cells
C) bind only to freely dissolved antigens in the plasma
D) bind to antigen fragments presented on major histocompatibility (MHC) complexes by host cells
E) bind to antigens that are either freely dissolved or present on the surface of invading or foreign cells

Question 34

You and a friend were in line for a movie when you noticed the woman in front of you sneezing and coughing. Both of you were equally exposed to the woman's virus, but over the next few days, only your friend acquired flu-like symptoms and was ill for almost a week before recovering. Which one of the following is a logical explanation for this?

A) Your friend had antibodies to that virus.
B) You had an adaptive immunity to that virus.
C) Your friend had an autoimmune disorder.
D) Your friend had allergies.

Question 35

CD4 and CD8 are ________.

A) proteins secreted by antigen-presenting cells
B) receptors present on the surface of natural killer cells
C) T-independent antigens
D) molecules present on the surface of T cells where they interact with major histocompatibility (MHC) molecules
E) molecules on the surface of antigen-presenting cells where they enhance B-cell activity

Question 36

The ability of one person to produce over a million different antibody molecules does not require over a million different genes; rather, this wide range of antibody production is due to ________.

A) alternative splicing of exons after transcription
B) increased rate of mutation in the RNA molecules
C) genetic DNA recombination
D) rearrangements of cytosolic proteins in the thymus cells
E) crossing over between the light and heavy chains of each antibody molecule during meiosis I

Question 37

B cells interacting with helper T cells are stimulated to differentiate when ________.

A) B cells produce IgE antibodies
B) B cells release cytokines
C) cytotoxic T cells present the class II MHC molecule-antigen complex on their surface
D) helper T cells differentiate into cytotoxic T cells
E) helper T cells release cytokines

Question 38

A newborn who is accidentally given a drug that destroys the thymus would most likely ________.

A) lack class I major histocompatability (MHC) molecules on cell surfaces
B) lack innate immunity
C) be unable to genetically rearrange antigen receptors
D) be unable to differentiate and mature T cells
E) have a reduced number of B cells and be unable to form antibodies

Question 39

Select the pathway that would lead to the activation of cytotoxic T cells.

A) B cell contacts antigen → helper T cell is activated → clonal selection occurs
B) body cell becomes infected with a virus → new viral proteins appear → class I MHC molecule-antigen complex displayed on cell surface
C) self-tolerance of immune cells → B cells contact antigen → cytokines released
D) complement is secreted → B cell contacts antigen → helper T cell activated → cytokines released
E) cytotoxic T cells → class II MHC molecule-antigen complex displayed → cytokines released → cell lysis

Question 40

The major histocompatibility (MHC) molecule is important in a T cell's ability to ________.

A) distinguish self from nonself
B) recognize specific parasitic pathogens
C) identify specific bacterial pathogens
D) identify specific viruses
E) recognize differences among types of cancer

Question 41

The cell-mediated immunity that destroys virally infected cells primarily involves ________.

A) cytotoxic T cells
B) inflammation
C) phagocytosis
D) macrophages
E) B cells

Question 42

Use the following information to answer the question(s) below.
An otherwise healthy student in your class is infected with EBV, the virus that causes infectious mononucleosis. The same student had already been infected when she was a child, at which time she had merely experienced a mild sore throat and swollen lymph nodes in her neck. This time, though infected, she does not get sick.
Her immune system's recognition of the second infection involves memory ________.

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

Question 43

A function of antibodies is to ________.

A) inject toxins into living pathogens
B) secrete cytokines that attract macrophages to infection sites
C) release major histocompatibility proteins to disrupt infected cells
D) act as Toll-like receptors
E) mark pathogenic cells for destruction

Question 44

For the successful development of a vaccine to be used against a pathogen, it is necessary that ________.

A) the surface antigens of the pathogen stay the same
B) a rearrangement of the B-cell receptor antibodies takes place
C) all of the surface antigens on the pathogen be identified
D) the pathogen have only one epitope
E) the major histocompatibility (MHC) molecules are heterozygous

Question 45

Which of the following cells are involved in cell-mediated immunity and also respond to class I MHC molecule-antigen complexes?

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

Question 46

Which of the following is a difference between class I and class II major histocompatibility complex (MHC) proteins?

A) Class I MHC proteins can be found on most cell types, whereas both class I and II MHC proteins are found on the antigen-presenting cells of the immune system
B) Class I MHC proteins are added to antigens in the cytoplasm, whereas class II proteins are added to antigens in the Golgi apparatus.
C) Class I MHC proteins signal the immune system to activate the cell displaying the message, whereas class II proteins signal the immune system to destroy a particular cell.
D) Class I and class II MHC proteins have the same basic role, but individuals with particularly strong immune systems will have both types, whereas most individuals have just one or the other.

Question 47

Your sister-in-law never gets sick, while her male neighbor seems to be sick all the time. Although there are several possible explanations for this, one is that they are genetically different. Which of the following hypotheses concerning genetic inheritance of major histocompatibility complex (MHC) molecules is consistent with this observation and your understanding of the immune system?

A) Individuals who are homozygous dominant for MHC genes are healthier than those who are homozygous recessive for MHC genes.
B) In the case of MHC, it is beneficial to have as many different alleles as possible, so individuals heterozygous for the multiple MHC genes are healthier than those who are mainly homozygous for MHC genes.
C) MHC proteins are often closely associated with small antigen particles that have been broken off the main pathogen, so individuals who are recessive for MHC don't normally have many illnesses because they don't produce these MHC-antigen complexes.
D) Some individuals undergo greater levels of somatic hypermutation for the MHC genes.

Question 48

Which of the following is a difference between B cells and T cells?

A) One has a major role in antibody production, while the other has a major role in cytotoxicity.
B) One binds a receptor called BCR (B-cell receptor), while the other recognizes a receptor called TCR (T-cell receptor).
C) B cells are activated by free-floating antigens in the blood or lymph. T cells are activated by plasma cells.
D) T cells are produced in the thymus and B cells are produced in the bone marrow.

Question 49

Phagocytosis of microbes by macrophages is enhanced by ________.
I) the binding of antibodies to the surface of microbes
II) antibody-mediated agglutination of microbes
III) the release of cytokines by activated B cells

A) only I and II
B) only II and III
C) only I and III
D) I, II, and, III

Question 50

Secondary immune responses upon a second exposure to a pathogen are due to the activation of ________.

A) memory cells
B) macrophages
C) stem cells
D) B cells
E) T cells

Question 51

A cell type that interacts with both the humoral and cell-mediated immune pathways is a ________.

A) plasma cell
B) cytotoxic T cell
C) natural killer cell
D) CD8 cell
E) helper T cell

Question 52

Why might humans need yearly vaccination for influenza?

A) There has been an increase in immunodeficiency diseases.
B) Influenza typically causes anaphylactic shock.
C) Memory B cells die out after one year.
D) Influenza virus undergoes rapid mutation that alters the surface proteins in the cells it infects.
E) Influenza initiates autoimmune disorders.

Question 53

Which of the following is crucial to activation of the adaptive immune response?

A) memory cells
B) presentation of MHC (major histocompatibility complex)-antigen complex on a cell surface
C) somatic hypermutation
D) phagocytosis of antibody-antigen complex by macrophages in the blood (the humoral response)

Question 54

A bone marrow transplant may not be appropriate from a given donor (Jane) to a given recipient (Jane's cousin Bob), even though Jane has previously given blood for one of Bob's needed transfusions, because ________.

A) Jane's major histocompatibility (MHC) proteins may not be a match
B) a blood-type match is less stringent than a match required for transplant because blood is more tolerant of change
C) Jane is heterozygous for MHC genes but Bob is not
D) Jane's MHC class II genes are not expressed in bone marrow
E) Bob's immune response is impaired

Question 55

When antibodies bind antigens, the clumping of antigens results from ________.

A) the antibody having at least two binding regions
B) disulfide bridges between the antigens
C) a complement protein that makes the affected cells sticky
D) bonds between class I and class II MHC molecules
E) denaturation of the antibodies

Question 56

Clonal selection is an explanation for how ________.

A) a single type of stem cell can produce both red blood cells and white blood cells
B) V, J, and C gene segments are rearranged
C) an antigen can provoke production of high levels of specific antibodies
D) HIV (human immunodeficiency virus) can disrupt the immune system
E) macrophages can recognize specific T cells and B cells

Question 57

The number of major histocompatibility (MHC) protein isoforms possible in a given human population is enormous. However, each individual has a limited array of MHC molecules because ________.

A) the MHC proteins are made from several different gene regions that are capable of rearranging in a number of ways
B) MHC proteins from one individual can only be of class I or class II
C) each of the MHC genes has a large number of alleles, but each individual inherits only two for each gene
D) once a B cell has matured in the bone marrow, it is limited to two MHC response categories
E) once a T cell has matured in the thymus, it can only respond to two MHC categories

Question 58

Immunological memory accounts for ________.

A) the human body's ability to distinguish self from nonself
B) the observation that some strains of the pathogen that causes dengue fever cause more severe disease than others
C) the ability of a helper T cell to signal B cells via cytokines
D) the ancient observation that someone who had recovered from the plague could safely care for those newly diseased
E) the ability of the immune system to present antigen fragments in association with major histocompatibility (MHC) antigens

Question 59

The primary function of humoral immunity (humoral response) is to ________.

A) defend against fungi and protozoa
B) reject transplanted tissues
C) protect the body against cells that become cancerous
D) protect the body against extracellular pathogens
E) defend against bacteria and viruses that have already infected cells

Question 60

If a patient is missing B and T cells, what would be absent from the immune response?

A) memory
B) lysozymes
C) cytokines
D) defense against bacteria
E) the innate immune response

Question 61

Which of the following is an example of a subunit vaccine?

A) An isolated surface protein of a target virus is used to make the vaccine.
B) The target virus is damaged by exposure to ultraviolet light.
C) The target virus is damaged by exposure to formaldehyde.
D) The target virus is grown in a host other than humans and thus grows more slowly than normal.

Question 62

Vaccination increases the number of ________.

A) different receptors that recognize a pathogen
B) lymphocytes with receptors that can bind to the pathogen
C) epitopes that the immune system can recognize
D) macrophages specific for a pathogen
E) major histocompatibility (MHC) molecules that can present an antigen

Question 63

A patient who has a high level of mast cell activity, dilation of blood vessels, and acute drop in blood pressure is likely suffering from ________.

A) an autoimmune disease
B) a typical skin allergy (contact dermatitis) that can be treated by antihistamines
C) an organ transplant, such as a skin graft
D) the effect of exhaustion on the immune system
E) anaphylactic shock immediately following exposure to an allergen

Question 64

Which of the following is TRUE of the humoral immune response and NOT true of the cell-mediated immune response? Only the humoral immune response ________.

A) involves T cells at some level
B) requires CD8+ cells for activation
C) involves destroying entire cells and not just the pathogen
D) uses antibodies as its main weapon

Question 65

Which of the following is the best definition of autoimmune disease?

A) a condition in which B cells and T cells respond independently to antigens and do not interact correctly
B) a condition in which the adaptive immune system fails to recognize the second infection by the same antigen
C) a condition in which self molecules are treated as nonself
D) a condition in which the immune system creates random antibodies without being triggered by an antigen

Question 66

The EBV antigen fragments will be presented by the virus-infected cells along with ________.

A) a complement
B) antibodies
C) class I MHC molecules
D) class II MHC molecules
E) dendritic cells

Question 67

The receptors on T cells and B cells bind to ________.

A) antibodies
B) antigens
C) natural killer cells
D) double-stranded RNA
E) immunoglobulins

Question 68

Which of the following should be the same in identical twins?

A) the set of antibodies produced
B) the set of major histocompatibility (MHC) molecules produced
C) the set of T-cell antigen receptors produced
D) the susceptibility to a particular virus
E) the set of immune cells eliminated as self-reactive

Question 69

A key part of the humoral immune response is ________.

A) the cytotoxic T-cell attack of infected host cells
B) the production of antibodies by plasma cells
C) perforation of infected host cells by perforin
D) phagocytosis of pathogens
E) the initiation of programmed cell death in infected host cells

Question 70

An invertebrate, such as an insect, has innate immunity activity in its intestine that likely includes ________.

A) memory cells
B) lysozyme
C) allergens
D) neutrophils
E) dendritic cells

Question 71

What is the best description of the hygiene hypothesis?

A) A high level of hygiene prevents autoimmune disorders.
B) A high level of hygiene prevents allergic reactions.
C) Hygienic practices that prevent intestinal worms lead to dysfunction of the immune system.
D) Poor hygiene leads to autoimmune disorders.

Question 72

A certain cell type has existed in the blood and tissue of its vertebrate host's immune system for over 20 years. One day, it recognizes a newly arrived antigen and binds to it, subsequently triggering a secondary immune response in the body. Which of the following cell types most accurately describes this cell?

A) plasma cell
B) thyroid cell
C) memory cell
D) macrophage

Question 73

What causes rejection by the body's immune system after a transplant of an improperly matched organ?
I) nonself proteins in the tissue
II) the presence of foreign major histocompatibility complex (MHC) proteins on the donor tissue
III) antibodies and cytotoxic T lymphocytes (CTLs) responding to foreign tissue

A) only I and III
B) only II and III
C) only I and IIII
D) I, II, and III

Question 74

Which of the following is TRUE of the allergic response?

A) Sufferers produce the IgE class of immunoglobulins in response to allergens.
B) Upon the very first exposure to an allergen, an allergy sufferer will experience anaphylactic shock.
C) It is a normal, healthy, adaptive response to an allergen.
D) Allergies are most common in people also responding to infections of intestinal worms.

Question 75

Which of the following would help a virus avoid triggering an effective adaptive immune response?
I) having frequent mutations in genes for surface proteins
II) building the viral shell from host proteins
III) producing proteins very similar to those of other viruses
IV) infecting and killing helper T cells

A) only I and III
B) only I, II, and IV
C) only II and IV
D) only I, II, and III
E) only II, III, and IV

Question 76

Infection with HIV (human immunodeficiency virus) typically ________.

A) kills macrophages and CD4+ T cells
B) eliminates all T cells initially
C) leads to an immediate decrease in the number of HIV particles in the blood
D) alters mitochondrial but not genomic DNA sequences
E) attacks B cells but not T cells

Question 77

In the human disease known as lupus, there is an immune reaction against a patient's own DNA from broken or dying cells; this categorizes lupus as ________.

A) an allergy
B) an immunodeficiency
C) an autoimmune disease
D) an antigenic variation
E) a cancer