Biol 102 Practice F1
The figure shows B cell antigen receptors and T cell antigen receptors. Each person makes more than 1 million different B cell antigen receptors and more than 10 million different T cell antigen receptors. How is such diversity in antigen receptors generated? A.By combining variable elements, the immune system assembles many different receptors from a much smaller collection of parts. B.A large percentage of the vertebrate genome is devoted to genes for individual antigen-binding sites. C.Genes for individual antigen-binding sites have a very high rate of mutation, generating great diversity.
A.By combining variable elements, the immune system assembles many different receptors from a much smaller collection of parts.
A newborn who is accidentally given a drug that destroys the thymus would most likely _____. A.be unable to differentiate and mature T cells B.lack innate immunity C.have a reduced number of B cells and be unable to form antibodies D.be unable to genetically rearrange antigen receptors
A.be unable to differentiate and mature T cells
Extracellular pathogens such as viruses and bacteria in body fluids are attacked by _____. A.cytotoxic T cells B.antigens C.antibodies from plasma cells D.helper T cells E.complement proteins
C.antibodies from plasma cells
True or False The word "antigen" and "virus" are interchangeable.
Fasle
Which of these cells is responsible for the rapidity of the secondary immune response? A.macrophages B.cytokines C.memory cells D.cytotoxic T cells E.plasma cells
C.memory cells
Select the correct statement about the immune system. A.All antigen receptors produced by a single B cell or T cell are identical and bind to the same epitope. B.Antibodies are secreted by T cells. C.Adaptive immunity is characteristic of invertebrates and vertebrates.
A.All antigen receptors produced by a single B cell or T cell are identical and bind to the same epitope.
What is the role of recombinase in generating lymphocyte diversity? A.Early in B cell development, recombinase links one light-chain V gene segment to one J gene segment. B.Recombinase combines DNA from human and viral origin. C.Recombinase splices RNA to produce variable transcripts.
A.Early in B cell development, recombinase links one light-chain V gene segment to one J gene segment.
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 allows for the destruction of antibodies. C.It enables an animal to counter most pathogens almost instantly the first time they are encountered. D.It results in effector cells with specificity for a large number of antigens.
A.It enables a rapid defense against an antigen that has been previously encountered.
Clonal selection is an explanation for how _____. A.an antigen can provoke production of high levels of specific antibodies B.V, J, and C gene segments are rearranged C.macrophages can recognize specific T cells and B cells D.HIV (human immunodeficiency virus) can disrupt the immune system
A.an antigen can provoke production of high levels of specific antibodies
Which of the following components of the immune system destroys bacteria in a way similar to an antitank weapon destroying armored military tanks by punching holes in the wall of the bacteria? A.complement protein B.major histocompatibility complex proteins C.macrophages D.plasma cells
A.complement protein
Vaccination increases the number of _____. A.lymphocytes with receptors that can bind to the pathogen B.macrophages specific for a pathogen C.epitopes that the immune system can recognize D.major histocompatability (MHC) molecules that can present an antigen
A.lymphocytes with receptors that can bind to the pathogen
If a patient is missing B and T cells, what would be absent from the immune response? A.memory B.cytokines C.defense against bacteria D.lysozymes
A.memory
Lymphocytes mature in the _____. I) spleen II) thymus III) bone marrow A.only II and III B.only I and II C.only I and III D.I, II, and III
A.only II and III
The role of cytotoxic T cells is the secretion of _____, which plays a role in the _____ immune response. A.perforin ... cell-mediated B.antibodies ... humoral C.perforin ... humoral D.interleukin-2 ... humoral E.antibodies ... antibody-mediated
A.perforin ... cell-mediated
Within a differentiated B cell, the rearrangement of DNA sequences between variable regions and joining regions is accomplished by a(n)_____. A.recombinase B.reverse transcriptase C.RNA polymerase D.epitopase
A.recombinase
The fluid with the highest osmolarity is _____. A.seawater in a tidal pool B.distilled water C.plasma in birds D.plasma in mammals
A.seawater in a tidal pool
Which of the following should be the same in identical twins? A.the set of major histocompatability (MHC) molecules produced B.the set of T cell antigen receptors produced C.the susceptibility to a particular virus D.the set of antibodies produced
A.the set of major histocompatability (MHC) molecules produced
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.the major histocompatability (MHC) molecules are heterozygous C.the pathogen has only one epitope D.all of the surface antigens on the pathogen be identified
A.the surface antigens of the pathogen stay the same
Jenner's successful use of cowpox virus as a vaccine against the smallpox virus was due to the fact that _____. A.there are some epitopes (antigenic determinants) common to both pox viruses B.the cowpox virus made antibodies in response to the presence of smallpox C.cowpox and smallpox are caused by the same virus D.the immune system responds nonspecifically to antigens
A.there are some epitopes (antigenic determinants) common to both pox viruses
The body fluids of an osmoconformer would be _____ with its _____ environment A. isoosmotic; freshwater B. isoosmotic; saltwater C. hyperosmotic; saltwater D. hypoosmotic; saltwater
B. isoosmotic; saltwater
Because antigen receptor genes are randomly rearranged, some immature lymphocytes produce receptors specific for epitopes on the organism's own molecules. Why doesn't the immune system attack these molecules on the body's cells and tissues? A.Only a very few lymphocytes produce receptors that attack the body's own molecules, so it's not a problem. B.B and T cells with receptors specific for the body's own molecules are destroyed by apoptosis. C.The body's cells are immune to such attack.
B.B and T cells with receptors specific for the body's own molecules are destroyed by apoptosis.
_____ interact with the antigen-class II MHC complex presented by macrophages. A.Bacterial cells B.Helper T cells C.Epithelial cells D.B cells E.Cytotoxic T cells
B.Helper T cells
Which is a true statement about memory cells? A.They engulf antigens bound by antibodies. B.They have a longer lifespan than plasma cells. C.The first time an antigen is encountered, memory cells become plasma cells. D.They produce antibodies.
B.They have a longer lifespan than plasma cells.
Helper T cells are part of _____. A.a group of phagocytic white blood cells B.cell-mediated immune responses C.innate immunity D.the complement system E.the first cells to bind to antigens
B.cell-mediated immune responses
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. The EBV antigen fragments will be presented by the virus-infected cells along with _____. A.class II MHC molecules B.class I MHC molecules C.a complement D.antibodies
B.class I MHC molecules
Compared to the seawater around them, most marine invertebrates are _____. A.hyperosmotic and isoosmotic B.isoosmotic C.hypoosmotic D.hyperosmotic
B.isoosmotic
Which of the following statements about epitopes are correct? I) B-cell receptors bind to epitopes. II) T-cell receptors bind to epitopes. III) There can be 10 or more different epitopes on each antigen. IV) There is a one-to-one correspondence between antigen and epitope. A.only II and IV B.only I, II, and III C.only II, III, and IV D.only I and III
B.only I, II, and III
B cells that have been stimulated by interleukin-2 develop into _____. A.helper T cells B.plasma cells C.cytotoxic T cells D.antigens E.macrophages
B.plasma cells
Immunological memory accounts for _____. A.the human body's ability to distinguish self from non-self B.the ancient observation that someone who had recovered from the plague could safely care for those newly diseased C.the observation that some strains of the pathogen that causes dengue fever cause more severe disease than others D.the ability of a helper T cell to signal B cells via cytokines
B.the ancient observation that someone who had recovered from the plague could safely care for those newly diseased
The switch of one B cell from producing one class of antibody to another class of antibody that is responsive to the same antigen is due to _____. A.a switch in the kind of antigen-presenting cell that is involved in the immune response B.the rearrangement of immunoglobulin heavy-chain C region DNA C.the rearrangement of V region genes in that clone of responsive B cells D.a patient's reaction to the first kind of antibody made by the plasma cells
B.the rearrangement of immunoglobulin heavy-chain C region DNA
Cell-mediated immunity differs from humoral immunity in that _____. A.a subsequent secondary immune response can occur in humoral immunity B.they respond differently to invaders C.a humoral response is mounted more quickly D.clonal selection occurs only in cell-mediated immunity E.cell-mediated immunity is longer lasting
B.they respond differently to invaders
How does an antihistamine reduce allergy symptoms? A.An antihistamine binds pollen antigens, preventing them from provoking an allergic reaction. B.An antihistamine kills mast cells, blocking an allergic reaction. C.An antihistamine blocks receptors for inflammatory chemicals released from granules within mast cells.
C.An antihistamine blocks receptors for inflammatory chemicals released from granules within mast cells.
What might this mean? A.He was probably exposed sometime within the past two weeks, but we don't have enough information to say more. B.He was probably exposed more than several months ago, antibody production has ceased, and antibodies are no longer detectable. C.He was probably exposed a few days ago and clonal selection has yet to produce plasma cells.
C.He was probably exposed a few days ago and clonal selection has yet to produce plasma cells.
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) Antigenic determinants from pathogen bind to antigen receptors on lymphocytes. IV) Lymphocytes specific to antigenic determinants from pathogen become numerous. V) Only memory cells remain. A.II → I → IV → III → V B.I → III → II → IV → V C.III → IV → II → I → V D.IV → II → III → I → V
C.III → IV → II → I → V
Which of the following is a difference between B cells and T cells? A.T cells are produced in the thymus and B cells are produced in the bone marrow. B.B cells are activated by free-floating antigens in the blood or lymph. T cells are activated by membrane-bound antigens. C.One has a major role in antibody production, while the other has a major role in cytotoxicity. D.One binds a receptor called BCR (B-cell receptor), while the other recognizes a receptor called TCR (T-cell receptor).
C.One has a major role in antibody production, while the other has a major role in cytotoxicity.
The role of active cytotoxic T cells is to attack _____. A.circulating antibodies B.circulating proteins C.body cells that have been infected D.complement proteins E.extracellular viruses and bacteria
C.body cells that have been infected
Osmoregulation and excretion are _____. A.mechanisms for the homeostatic control of body temperature B.ways that animals control their external environment C.mechanisms that maintain volume and composition of body fluids D.mechanisms that require continual water loss E.chemical processes that completely stop during torpor and hibernation
C.mechanisms that maintain volume and composition of body fluids
A certain cell type has existed in the blood and tissue of its vertebrate host's immune system for over twenty 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.macrophage C.memory cell D.thyroid cell
C.memory cell
An immunoglobulin (Ig) molecule, of whatever class, with regions symbolized as C or V, H or L, has a light chain made up of _____. A.three H regions and one L region B.one H region and one L region C.one C region and one V region D.two C regions and two V regions
C.one C region and one V region
Yearly vaccination of humans for influenza viruses is necessary because _____. A.surviving the flu one year exhausts the immune system to nonresponsiveness the second year B.the flu can generate anaphylactic shock C.rapid mutation in flu viruses alters the surface proteins in infected host cells D.of an increase in immunodeficiency diseases
C.rapid mutation in flu viruses alters the surface proteins in infected host cells
Clonal selection and differentiation of B cells activated by antigen exposure leads to the production of _____. A.long-lived erythrocytes that can later secrete antibodies for the antigen B.large quantities of the antigen initially recognized C.short-lived plasma cells that secrete antibodies for the antigen D.vast numbers of B cells with random antigen-recognition receptors
C.short-lived plasma cells that secrete antibodies for the antigen
Clonal selection is the division of _____ that have been stimulated by binding to an antigen, which results in the production of cloned _____. A.helper T cells ... plasma cells B.macrophages ... B cells and T cells C.T cells ... B cells D.B cells ... plasma cells and memory cells E.B cells ... macrophages
D.B cells ... plasma cells and memory cells
Which of the following pairs of proteins shares the most overall similarity in structure? A.T-cell receptors and antibodies B.antibodies and antigens C.B-cell receptors and T-cell receptors D.B-cell receptors and antibodies
D.B-cell receptors and antibodies
An individual who has been bitten by a poisonous snake that has a fast-acting toxin would likely benefit from _____. A.injection of interferon B.injection of interleukin-1 C.vaccination with a weakened form of the toxin D.injection of antibodies to the toxin
D.injection of antibodies to the toxin
A primary reason for needing a new vaccine for influenza each year is that _____. A.the influenza virus might proliferate in different tissues during each subsequent year, and immune memory is limited to those tissues initially infected B.the first infection with influenza weakens the immune system C.influenza is a disease that causes the apoptosis of all memory cells D.mutation in the influenza virus is frequent E.immunity typically disappears one month after recovery from a disease
D.mutation in the influenza virus is frequent
Which of the following statements are fundamental to 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 II and IV B.only II, III, and IV C.only I and III D.only I, II, and IV
D.only I, II, and IV
What type of immunity is associated with breast feeding? A.active immunity B.innate immunity C.cell-mediated immunity D.passive immunity
D.passive immunity
Naturally acquired passive immunity can result from the _____. A.ingestion of interferon B.absorption of pathogens through mucous membranes C.injection of vaccine D.placental transfer of antibodies
D.placental transfer of antibodies
Which of these cells produce and secrete antibodies? A.helper T cells B.bacterial cells C.macrophages D.plasma cells E.cytotoxic T cells
D.plasma cells
The fact that there are about a million different antigen receptors possible in human B cells is based on _____. A.constant changes in the splicing pattern of receptor genes after the differentiation of the B cell B.temporary changes in the ways that RNA is spliced in the B cells C.having one million different immunoglobulin genes D.recombination of the segments of the receptor DNA that make up the functional receptor genes of differentiated B cells E.the capacity of memory cells to produce antibodies
D.recombination of the segments of the receptor DNA that make up the functional receptor genes of differentiated B cells
When antibodies bind antigens, the clumping of antigens results from _____. A.bonds between class I and class II MHC molecules B.disulfide bridges between the antigens C.denaturation of the antibodies D.the antibody having at least two binding regions
D.the antibody having at least two binding regions
The force driving simple diffusion is _____, while the energy source for active transport is _____. A.phosphorylated protein carriers; ATP B.transmembrane pumps; electron transport C.the concentration gradient; ADP D.the concentration gradient; ATP
D.the concentration gradient; ATP
Tissues are immunogically "typed" before an organ transplant to make sure that the donor and recipient match as closely as possible in their _____. A.T cells B.B cells C.histamines D.antibodies E.MHC (major histocompatibility complex) proteins
E.MHC (major histocompatibility complex) proteins
An antigen _____. A.could be an invading bacterium B.induces development of white blood cells in the bone marrow C.is a protein attacked by an invading microorganism D.is a protein molecule that helps defend the body against disease E.is a foreign molecule that evokes a specific response by a lymphocyte
E.is a foreign molecule that evokes a specific response by a lymphocyte
Which of these cells is a phagocytic leukocyte that can engulf a foreign bacterium? A.plasma cell B.helper T cell C.B cell D.cytotoxic T cell E.macrophage
E.macrophage
