Deck 47: Animal Defenses Against Infection

Question 1

Vertebrate immune cells, which are phagocytic, include which of the following?
I) neutrophils
II) macrophages
III) dendritic cells
IV) natural killer cells

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

Answer 1

D

Question 2

A strain of fruit fly lacks the ability to produce Dicer-2 protein will most likely be susceptible to which of the following types of infections?

A) viral
B) bacterial
C) fungal
D) protozoan

Answer 2

A

Question 3

Mucus occurs in both the respiratory and digestive tracts. Which answer best describes the main immunological function of mucus?

A) to sweep away debris
B) to physically trap pathogens
C) to destroy pathogens (because mucus is acidic)
D) to increase oxygen absorption

Answer 3

B

Question 4

Which statement correctly describes the complement system?

A) a set of proteins involved in innate but not acquired immunity
B) a group of proteins that includes interferons and interleukins
C) a group of proteins that act together in a cascade fashion
D) a set of proteins that act individually to attack and lyse microbes

Question 5

Use the graphs to answer the following question.
Mutant fruit flies that do not make antimicrobial peptides were tested for survival after infection with Neurospora crassa fungi or with Micrococcus luteus bacteria. The mutant flies were also transfected with the genes for antimicrobial peptides (drosomycin or defensin) and tested for survival.

Which of the following hypotheses is best supported using the data?

A) adding the defensin gene to such mutants protects them from death by bacterial infection
B) adding the drosomycin gene to such mutants protects them from death by bacterial infection
C) wild-type flies with the full set of genes for antimicrobial peptides are highly susceptible to both fungal and bacterial pathogens
D) the presence of any single antimicrobial peptide protects against both fungal and bacterial pathogens

Question 6

Benadryl is an antihistamine. Which of the following is most likely to occur if a person that was stung by a bee takes Benadryl?

A) the site of injury will become less red and swollen
B) more antibodies will be produced
C) more histamine will be released
D) the thymus will become enlarged

Question 7

You and your friend were equally exposed to a 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 inflammatory response worked more quickly than your friend's response.
B) You had an immunological memory of that virus.
C) Your friend had an autoimmune disorder.
D) Your friend had allergies.

Question 8

Which of the following protects both the eyes and the respiratory tract against infections?

A) interferons produced by immune cells
B) the secretion of complement proteins
C) the release of slightly alkaline secretions
D) the secretion of lysozyme onto their surfaces

Question 9

Which of the following cells and signaling molecules are involved in the initial stages of the inflammatory response?

A) phagocytes and cytokines
B) dendritic cells and interferons
C) mast cells and histamines
D) lymphocytes and interferons

Question 10

A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. Which type of response is most consistent with these symptoms?

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

Question 11

Within a differentiated B cell, the activity of which molecule results in the rearrangement of DNA sequences between variable regions and joining regions?

A) RNA polymerase
B) reverse transcriptase
C) telomerase
D) recombinase

Question 12

A phagocytic cell has a mutation in a gene for a hydrolytic enzyme that renders the enzyme nonfunctional. What is the most likely effect of the mutation when this phagocytic cell ingests a pathogen?

A) the pseudopodia will not be able to surround the pathogen as well
B) a vacuole will not form
C) the lysosome will not degrade the pathogen effectively
D) pathogen debris will not exit the cell via exocytosis

Question 13

Which of the following can trigger septic shock?

A) certain bacterial infections
B) specific forms of viruses
C) the presence of natural killer cells
D) increased production of neutrophils

Question 14

Acidity in human sweat is part of which type of immune system?

A) cell-mediated immune responses
B) acquired immunity
C) adaptive immunity
D) innate immunity

Question 15

Which statement is true about innate immunity?

A) Innate immunity is the first, and most general, mechanism of protection against pathogens.
B) The extent of an innate immunity response depends on an infected animal's previous exposure to a pathogen
C) Innate immunity is based on recognition of antigens that are specific to a pathogen
D) Only vertebrates use innate immunity

Question 16

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

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

Question 17

Which response is triggered when bacteria enter the body through a small cut in the skin?

A) inactivation of erythrocytes
B) apoptosis of nearby body cells
C) release of interferons
D) activation of a group of proteins called complement

Question 18

Which of the following are molecules on mammalian cells that recognize macromolecules that are present in or on certain groups of pathogens?

A) cytokines
B) toll-like receptors
C) interferons
D) complement proteins

Question 19

Which of the following are typical features of an inflammatory response?

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

Question 20

An organism that lacks their thymus would ________.

A) lack innate immunity
B) be unable to genetically rearrange antigen receptors
C) be unable to differentiate and mature T cells
D) have a reduced number of B cells and be unable to form antibodies

Question 21

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 22

Use the following information to answer the following question.
An otherwise healthy student in your class was infected with Epstein Barr virus (EBV) (the virus that causes infectious mononucleosis) when she was a child, at which time she had merely experienced a mild sore throat and swollen lymph nodes in her neck. When she is exposed to EBV again later in life, she does not get sick or develop any symptoms of mononucleosis.
Which of the following statements explains why your classmate does not exhibit symptoms of EBV infection?

A) She was infected with a weaker strain of EBV during her second exposure.
B) Complement proteins effectively controlled the EBV during the second infection.
C) Memory T cells recognized the virus upon the second exposure and activated cells that destroyed the virally infected cells.
D) Her innate immune response was better at recognizing the EBV antigen during the second infection.

Question 23

Which statement best describes what causes the clumping of antigens when antibodies bind antigens?

A) the antibody has two identical binding sites
B) disulfide bridges form between the antigens
C) bonds form between class I and class II MHC molecules
D) the antibodies denature

Question 24

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

Question 25

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 initiating 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 26

Which of the following statements about epitopes is incorrect?

A) B cell receptors bind to epitopes.
B) T cell receptors bind to epitopes.
C) There can be 10 or more different epitopes on each antigen.
D) There is a one-to-one correspondence between antigen and epitope.

Question 27

Which statement best describes an account of immunological memory?

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 observation that someone who had recovered from the plague could safely care for those newly diseased

Question 28

Which answer describes an advantage of 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 with specificity for a large number of antigens.
D) It allows for the production of only a single type of antibody.

Question 29

Breast feeding confers which type of immunity to an infant?

A) innate immunity
B) active immunity
C) passive immunity
D) cell-mediated immunity

Question 30

Which of the following statements describe a component of the clonal selection theory of how the adaptive immune system functions?
I) Each lymphocyte has a unique membrane receptor that recognizes one antigen.
II) When the lymphocyte binds an antigen, it 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) I, II, and IV
D) II, III, and IV

Question 31

If a T cell antigen receptor was composed of only a single alpha chain, the receptor would ________.

A) bind to a wider variety of antigens
B) not penetrate the cell membrane
C) resemble a B cell receptor
D) not be able to bind to antigens effectively

Question 32

A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable to ________.

A) respond to circulating viral antigens
B) lyse tumor cells
C) stimulate a cytotoxic T cell
D) interact with a class II MHC-antigen complex

Question 33

Which statement correctly describes both CD4 and CD8 proteins?

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

Question 34

Vaccination offers protection against future exposure to pathogens because it ________.

A) stimulates the complement system
B) triggers clonal expansion of lymphocytes
C) promotes inflammation
D) enhances the activity of macrophages

Question 35

Which of the following are similarities between B cells and T cells?
I) Both recognize antigens using immunoglobulin receptors.
II) Both undergo clonal selection after encountering an antigen.
III) Both maintain an immunological memory of previously encountered antigens.

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

Question 36

B cells are stimulated to differentiate under which of the following conditions?

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 release cytokines

Question 37

Which of these is a characteristic of adaptive immunity but not innate immunity?

A) memory
B) inflammation
C) interferons
D) lysozyme

Question 38

Which statement best describes the concept of clonal selection?

A) V, J, and C gene segments are rearranged
B) an antigen can provoke production of high amounts of specific antibodies
C) HIV (human immunodeficiency virus) can disrupt the immune system
D) macrophages can recognize specific T cells and B cells

Question 39

Which of the following components make up a light chain of an immunoglobulin (Ig) molecule, of any class, with regions symbolized as C or V, H or L?

A) one C region and one V region
B) one H region and one L region
C) three H regions and one L region
D) two C regions and two V regions

Question 40

Which option best describes how a viral antigen, like EBV, is recognized by T cells?

A) An antigen fragment is presented within class I MHC to the T cell receptor.
B) Interferon proteins stick to the surface of infected cells.
C) T cells recognize antibodies that have bound to viral particles.
D) The virus is engulfed by T cells using Toll-like receptors.

Question 41

Which option best describes why Jenner's use of cowpox virus as a vaccine against the smallpox virus was successful?

A) the immune system responds nonspecifically to antigens
B) the cowpox virus made antibodies in response to the presence of smallpox
C) there are some epitopes (antigenic determinants) common to both pox viruses
D) cowpox and smallpox are caused by the same virus

Question 42

The number of major histocompatibility (MHC) protein combinations possible in a given population is enormous. However, an individual in the population has a far more 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 only inherits two for each gene
D) once a B cell has matured in the bone marrow, it is limited to two MHC response categories

Question 43

Which of these is not part of insect immunity?

A) enzyme activation of pathogen-killing chemicals
B) activation of natural killer cells
C) phagocytosis by hemocytes
D) production of antimicrobial peptides

Question 44

Which of the following can result in naturally acquired passive immunity?

A) injection of vaccine
B) ingestion of interferon
C) placental transfer of antibodies
D) absorption of pathogens through mucous membranes

Question 45

Which of the following components of the immune system is most likely to be the same in identical twins?

A) the types of antibodies produced
B) the kinds of major histocompatibility (MHC) molecules produced
C) the set of T cell antigen receptors produced
D) the susceptibility to a particular virus

Question 46

The figure shows the progress of an untreated HIV infection. Which curve represents the concentration of helper T cells in the blood?

A) curve A
B) curve B
C) curve C
D) None of the curves show helper T cell concentration.

Question 47

Some people are allergic to dust mites, which are tiny insects that commonly live in house dust. Which of the following is the most immediate outcome if someone who is allergic to dust mites inhales dust years after they are first exposed to dust mites?

A) IgE antibodies are produced and bind to receptors on mast cells
B) IgE antibodies bound to mast cells bind the dust mite allergen
C) IgE antibodies bound to mast cells bind to each other
D) IgE antibodies bound to mast cells trigger the production of histamine

Question 48

Wiskott-Aldrich syndrome is an inherited X-linked recessive disorder characterized by low platelet count and a compromised immune system among other symptoms. Which answer best describes Wiskott-Aldrich syndrome?

A) autoimmune disease
B) inborn immunodeficiency disease
C) acquired immunodeficiency disease
D) allergy

Question 49

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 I, II, and III
D) only II, III, and IV

Question 50

An epitope associates with which part of an antigen receptor or antibody?

A) the tail
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

Question 51

Which of the following best explains why a bone marrow transplant may not be appropriate from a given donor to a given recipient even though they are compatible for blood transfusions?

A) their blood-types may match but 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) there is only one allele for blood-type, but there are many alleles for bone-marrow type
D) the given donor's MHC class II genes are not expressed in bone marrow

Question 52

Which of the following gives the best example for the ability of some viruses to remain inactive (latent) for a period of time?

A) influenza, a particular strain of which returns every 10-20 years
B) herpes simplex viruses (oral or genital) whose reproduction is triggered by physiological or emotional stress in the host
C) Kaposi's sarcoma, which causes a skin cancer in people with AIDS but rarely in those not infected by HIV
D) the virus that causes a form of the common cold, which recurs in patients many times in their lives

Question 53

A patient has a high level of mast cell activity, dilation of blood vessels, and acute drop in blood pressure. Which condition is most consistent with these symptoms?

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) anaphylactic shock immediately following exposure to an allergen

Question 54

Which treatment is most appropriate for an individual complaining of watery, itchy eyes and sneezing after being given a flower bouquet?

A) a vaccine
B) sterile pollen
C) antihistamines
D) monoclonal antibodies

Question 55

Yearly vaccinations for influenza viruses are necessary for humans because ________.

A) of an increase in immunodeficiency diseases
B) the flu can generate anaphylactic shock
C) surviving the flu one year renders the immune system to be nonresponsive the next year
D) rapid mutation in flu viruses alters the surface proteins in infected host cells

Question 56

Which of the following components of the immune system destroys cancer cells by forming holes in plasma membranes and triggering apoptosis?

A) toll-like proteins
B) macrophages
C) plasma cells
D) cytotoxic T cells

Question 57

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) activation of complement proteins
D) phagocytosis of antibody-antigen complex by macrophages in the blood

Question 58

Which of the following enhances phagocytosis of microbes by macrophages?
I) the binding of antibodies to the surface of microbes
II) antibody-mediated opsonization 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 59

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

A) a condition in which B and T cells trigger anaphylactic shock in response to an antigen
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 (loss of self-tolerance)
D) a condition in which the immune system creates random antibodies without being triggered by a specific antigen

Question 60

Which treatment could relieve the symptoms of an individual who has been bitten by a poisonous snake that has a fast-acting toxin?

A) vaccination with a weakened form of the toxin
B) injection of antibodies to the toxin
C) injection of interleukin-1
D) injection of interferon

Question 61

Which of the following statements is not true?

A) An antibody has more than one antigen-binding site.
B) A lymphocyte has receptors for multiple different antigens.
C) An antigen can have different epitopes.
D) A liver or muscle cell makes one class of MHC molecule.

Question 62

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

A) the set of antibodies produced
B) the set of MHC molecules produced
C) the set of T cell antigen receptors produced
D) the set of immune cells eliminated as self-reactive

Question 63

Which of the following would not help a virus avoid triggering an adaptive immune response?

A) having frequent mutations in genes for surface proteins
B) infecting cells that produce very few MHC molecules
C) producing proteins very similar to those of other viruses
D) infecting and killing helper T cells

Question 64

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

A) B cells confer active immunity; cytotoxic T cells confer passive immunity.
B) B cells respond the first time a pathogen is present; cytotoxic T cells respond subsequent times.
C) B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells.
D) B cells carry out the cell-mediated response; cytotoxic T cells carry out the humoral response.

Question 65

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) MHC molecules that can present an antigen