Deck 49: The Immune System in Animals

Question 1

Which of the following statements is not fundamental to the clonal-selection theory of how the adaptive immune system functions?

A)Each lymphocyte has a unique membrane receptor that recognizes one antigen.
B)When the lymphocyte binds an antigen,it is activated and begins dividing to form many identical copies of itself.
C)Cloned lymphocytes have slight differences and are selected by the spleen for removal if they do not bind an antigen.
D)Cloned cells descend from an activated lymphocyte and persist even after the pathogen is eliminated.

Answer 1

C

Question 2

Which of the following would put you at increased risk of pathogens entering your body?

A)a mutation that increases the amount of lysozyme you can produce
B)a mutation that increases the amount of wax your ears produce on a daily basis
C)a mutation that causes your mucus secretions to be extremely watery
D)a mutation that decreases the number of cilia present in the respiratory tract

Answer 2

C

Question 3

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)amino terminus of light and heavy chains
C)carboxy terminus of light and heavy chains
D)the region projecting into the cytoplasm of the cell

Answer 3

B

Question 4

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 5

Mucus occurs in both the respiratory and digestive tracts.What is its main immunological function?

A)sweeping away debris
B)physically trapping pathogens
C)destruction of pathogens because it is acidic
D)increasing oxygen absorption

Question 6

You are playing a new video game that is based on the human immune system.The player is inside a human,and you must successfully fend off invading pathogens in a quest to find the "Golden Antibody." At level 1,your arsenal for fighting off pathogens consists only of the innate immunity leukocytes and their various secretions.If the enemy has killed off most of your neutrophils and macrophages,which of the following should you utilize to recruit more of these leukocytes to the battle?

A)histamine
B)platelets
C)reactive oxygen species
D)cytokines
E)bone marrow

Question 7

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)recist tumor response

Question 8

Which of the following statements is not true of epitopes?

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 9

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

A)You have an innate immunity to that virus.
B)You have an adaptive immunity to that virus.
C)Your friend has an autoimmune disorder.
D)Your friend has allergies.

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.
C)It allows for a broad specificity for defense against antigens.
D)It allows for the destruction of antibodies.

Question 11

Lymphocytes are formed in what organ(s)?

A)spleen
B)thymus
C)bone marrow
D)spleen and bone marrow
E)thymus and bone marrow

Question 12

Which of the following is an antigen?

A)Antigens are immunoglobulins.
B)Antigens are used by the immune system to neutralize foreign objects.
C)Antigens are molecules used during an immune response to enhance the binding of antibodies to damaged cells.
D)Antigens are produced by white blood cells.

Question 13

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 uses a receptor called BCR,while the other recognizes a receptor called TCR.
C)B cells are activated by free-floating antigens in the blood or lymph.T cells are activated by membrane-bound antigens.
D)T cells are produced in the thymus and B cells are produced in the bone marrow.

Question 14

What kind of immune responses do insects have?

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

Question 15

You cut your finger,and after putting pressure on the wound for several minutes,you notice that it is still bleeding profusely.What may be the problem?

A)Platelets are not functioning properly,or there are too few to be effective.
B)Mast cells are not releasing their chemical messengers.
C)There are too many antigens to allow clotting.
D)Hemoglobin levels are too high to allow clotting.

Question 16

Which of the following pairs of proteins shares the most overall similarity in structure?

A)B-cell receptors and T-cell receptors
B)B-cell receptors and antibodies
C)T-cell receptors and antibodies
D)antibodies and antigens

Question 17

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 the self molecules are treated as non-self
D)a condition in which the immune system creates random antibodies without being triggered by an antigen

Question 18

If a patient only has neutrophils and macrophages,what would be absent from the immune response?

A)memory
B)lysozymes
C)cytokines
D)defense against bacteria

Question 19

Mast cells can both constrict and dilate blood vessels after injury.Which of the following best explains why both of these events occur shortly after tissue is injured?

A)Different blood vessels respond to the same messenger from mast cells in different ways for example,larger vessels constrict to reduce blood loss while smaller ones dilate to promote blood flow to the injured tissue.
B)Mast cells release different chemical messengers,one that causes constriction in the region of blood loss,and another that causes dilation away from the injury to promote quicker healing.
C)Mast cells release one chemical messenger immediately after injury that constricts vessels to promote clotting;after bleeding has stopped,they release another messenger that causes those same vessels to dilate,which increases blood flow to promote healing.
D)Mast cells release different chemical messengers,one that causes vessels away from the site of the injury to constrict to control blood loss,and another that causes vessels near the injury to dilate to promote quicker healing.

Question 20

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

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

Question 21

Which of the following are effective treatments for some allergic reactions?

A)antihistamines
B)epinephrine
C)corticosteroids
D)antihistamines,epinephrine,and corticosteroids
E)both antihistamines and epinephrine

Question 22

What causes rejection by the body's immune system after a transplant of an improperly matched organ?

A)non-self proteins in the tissue
B)the presence of foreign MHC proteins on the donor tissue
C)antibodies and cytotoxic T lymphocytes (CTLs)responding to foreign tissue
D)non-self proteins in the tissue,the presence of foreign MHC proteins on the donor tissue,and antibodies and cytotoxic T lymphocytes (CTLs)responding to foreign tissue
E)Both non-self proteins in the tissue and antibodies and cytotoxic T lymphocytes (CTLs)responding to foreign tissue can cause an organ to be rejected.

Question 23

Use the following information when answering the corresponding question(s).
Oysters live attached to substrate in estuaries and can experience low oxygen and elevated carbon dioxide conditions,especially in midsummer.Oysters also suffer high mortality in the summer.Researchers wanted to find out if the low-oxygen or elevated carbon dioxide conditions compromised the immune system of oysters.The immune system of oysters includes cells called hemocytes that phagocytose foreign particles and remove them from tissues.These phagocytic hemocytes also initiate the production and release of reactive oxygen intermediates (ROIs),including HOCl,O₂⁻,and H₂O₂.ROIs attack and kill invading cells.The researchers maintained oysters at normal oxygen conditions and low-oxygen conditions at a level commonly found in estuaries in the summer.While varying oxygen levels,they kept carbon dioxide concentrations constant.They also examined the effect of different carbon dioxide concentrations when oxygen levels were kept constant.They found that production of ROIs under low-oxygen conditions was only 33% of ROI production in normal oxygen conditions.There was no detectable effect of carbon dioxide levels on ROI production.Other researchers have found that the amount of phagocytosis is not affected by oxygen conditions.(J.N.Boyd and L.E.Burnett.1999.Reactive oxygen intermediate production by oyster hemocytes exposed to hypoxia.Journal of Experimental Biology 202:3135-43. )
Refer to the paragraph on the effects of low oxygen and elevated carbon dioxide on oysters.Why did the researchers keep carbon dioxide levels constant while they varied oxygen levels and then keep oxygen levels constant while they varied carbon dioxide levels?

A)It is technically easier to vary the level in the water of one gas at a time.
B)They could only measure the level of one gas in the water at a time.
C)The effects of oxygen and carbon dioxide levels could interact.
D)Only one gas at a time varies in estuaries in the summer.

Question 24

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

A)The surface protein of a virus is used to make the vaccine.
B)The virus is exposed to ultraviolet light.
C)The virus is exposed to formaldehyde.
D)The virus is grown in a host other than humans and thus grow more slowly than normal.

Question 25

Use the following information when answering the corresponding question(s).
Oysters live attached to substrate in estuaries and can experience low oxygen and elevated carbon dioxide conditions,especially in midsummer.Oysters also suffer high mortality in the summer.Researchers wanted to find out if the low-oxygen or elevated carbon dioxide conditions compromised the immune system of oysters.The immune system of oysters includes cells called hemocytes that phagocytose foreign particles and remove them from tissues.These phagocytic hemocytes also initiate the production and release of reactive oxygen intermediates (ROIs),including HOCl,O₂⁻,and H₂O₂.ROIs attack and kill invading cells.The researchers maintained oysters at normal oxygen conditions and low-oxygen conditions at a level commonly found in estuaries in the summer.While varying oxygen levels,they kept carbon dioxide concentrations constant.They also examined the effect of different carbon dioxide concentrations when oxygen levels were kept constant.They found that production of ROIs under low-oxygen conditions was only 33% of ROI production in normal oxygen conditions.There was no detectable effect of carbon dioxide levels on ROI production.Other researchers have found that the amount of phagocytosis is not affected by oxygen conditions.(J.N.Boyd and L.E.Burnett.1999.Reactive oxygen intermediate production by oyster hemocytes exposed to hypoxia.Journal of Experimental Biology 202:3135-43. )
Based on the information on the effects of low oxygen and elevated carbon dioxide on oysters,which of the following is the most likely explanation for the effect of oxygen levels on production of reactive oxygen intermediates (ROIs)?

A)Carbon dioxide buildup prevents formation of ROIs under low-oxygen conditions.
B)Under low-oxygen conditions,there is not enough oxygen to produce as many ROIs.
C)Phagocytic hemocytes are not as active when oxygen levels are low,so they cannot produce as many ROIs.
D)ROIs are less effective at killing cells under low-oxygen conditions,so phagocytic hemocytes do not produce as many.

Question 26

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 and signals that this cell has been compromised,while Class II proteins are found on cells of the immune system and are designed to activate immune responses.
B)Class I MHC proteins are added to antigens in the cytoplasm,while 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,while 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 while most individuals have just one or the other.

Question 27

Which lymphocytes act indirectly to produce antibodies?

A)macrophage
B)CD4+ T cell
C)CD8+ T cell
D)B cell
E)all of the above

Question 28

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)macrophages
C)plasma cells
D)major histocompatibility complex proteins

Question 29

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)B cell
B)T cell
C)memory cell
D)macrophage

Question 30

Which of the following is true of the allergic response?

A)Sufferers produce the IgE class of gamma globulins in response to allergens.
B)Upon the very first exposure to an allergen,an allergy sufferer will probably experience a runny nose,watery eyes,and mild wheezing.
C)It is a normal,healthy,adaptive response to an allergen.
D)All of the above answers are true.

Question 31

Which of the following is true of the humoral immune response and not true of the cell-mediated immune response?

A)involves T cells at some level
B)require CD8+ cells for activation
C)involves destroying entire cells and not just the pathogen
D)uses antibodies as its main weapon
E)All of these answers are true of the humoral immune response and not true of the cell-mediated immune response.

Question 32

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

A)MHC inheritance works like normal Mendelian genetics in the sense that there are dominant traits and recessive traits,and in the case of MHC,those with the dominant trait (including both those who are heterozygous and homozygous dominant)produce more normal MHC proteins and are healthier than those with the recessive trait (homozygous recessive).
B)In the case of MHC,it is beneficial to have as many different alleles as possible,so heterozygous individuals are healthier than homozygous dominant or recessive individuals.
C)MHC proteins are often closely associated with small antigen particles that have been broken off the main pathogen,so that individuals who are recessive for MHC don't normally have many illnesses because they don't produce these MHC-antigen complexes.
D)MHC inheritance is X-linked and thus males will have a higher percentage of weak immune systems than females do.