Deck 49: The Immune System in Animals

Question 1

Which of the following statements about epitopes is false?

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.

Answer 1

D

Question 2

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 acquired immune system fails to recognize the second infection by the same antigen
C)a condition in which a molecule belonging to the host is treated like an antigen and triggers an immune response
D)a condition in which the immune system creates random antibodies without being triggered by an antigen

Answer 2

C

Question 3

Which of the following statements is not fundamental to the clonal-selection theory of how the acquired 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 3

C

Question 4

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 acquired immunity to that virus.
C)Your friend does not have the ability to fight off that particular virus.
D)Answers B and C are both correct.

Question 5

Lymphocytes are formed in what organ(s)?

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

Question 6

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

Question 7

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

A)a mutation preventing you from making lysozyme
B)cleaning the wax out of your ears on a daily basis
C)a mutation that causes your mucus secretions to be extremely watery
D)all of the above
E)A and C only

Question 8

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 9

Which of the following best describes what an antigen is?

A)a molecule,such as a polypeptide or carbohydrate,that initiates a response from the immune system
B)a protein in the immune system that is used to identify potential pathogens
C)a molecule that is used during an immune response to enhance the binding of antibodies to damaged cells
D)all of the above

Question 10

A small child falls down and cuts his knee.A few days later a scab forms over the wound.After a few weeks,the wound does not appear to be healing,but it is not infected.Which of the following could explain this?

A)The child has a neutrophile deficiency.
B)The child has a platelet deficiency.
C)The child has a cytokine deficiency.
D)The child has a mast cell deficiency.
E)Answers C or D are possible.

Question 11

It is commonly know that breast milk provides many benefits to a newborn baby because it provides immune benefits.Which of the following immunoglobulins play a role in this?

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

Question 12

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 13

In previous chapters,you learned about osmotic and diffusion gradients that aid in maintaining water and ion balance and in developing resting potentials in cells,among other important biological features.How does the immune system of vertebrates exploit a chemical 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 14

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)Answers A and B are both correct.
E)Answers B and C are both correct.

Question 15

What kind of immune responses do insects have?

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

Question 16

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)innate immune response
B)acquired immune response
C)inflammation
D)both A and C
E)both B and C

Question 17

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 18

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 19

What do neutrophils and macrophages have in common?

A)Both ingest and kill bacteria.
B)Both arrive simultaneously at a wound site.
C)Both secrete cytokines.
D)Both secrete lysozymes.

Question 20

What major advantage is conveyed by having a system of acquired 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 extremely precise specificity for defense against antigens.
D)All of the above answers are correct.
E)Answers A and C are both correct.

Question 21

What would be the consequence(s)of a mutation that did not allow for selection against self-responding lymphocytes (those that respond against self)?

A)The immune system would fail and the individual would catch many illnesses.
B)This would likely be a fatal condition as the lymphocytes would attack all self cells.
C)The lymphocytes would be more likely to recognize antigens they had previously been exposed to.

Question 22

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

A)antihistamines
B)epinephrine
C)corticosteroids
D)all of the above
E)both A and B

Question 23

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 24

What is the difference between a secondary immune response occurring without a vaccine compared to the same response occurring after a vaccine?

A)A person who has received a vaccine does not have a secondary response,while someone without a vaccine does.
B)A person who has received a vaccine may have a secondary immune response on the first exposure to the normal,living pathogen.
C)Even with a vaccine,someone must still go through development of memory cells before they can have a secondary response.
D)All of the above answers apply.
E)Only answers B and C apply.

Question 25

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 26

Home blood typing kits reveal an individual's blood type by interpreting how blood reacts when exposed to antibodies.Which of the following is studied to interpret the results using these types of kits?

A)complementation
B)agglutination
C)hypersensitivity
D)autoimmunity

Question 27

Based on the above information,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 28

Which of the following is a difference between a primary and a secondary immune response?

A)The secondary response comes immediately after the primary response.
B)The secondary response involves memory cells,the primary does not.
C)The primary response involves immunological memory whereas the secondary response does not.
D)The primary response generates an allergy,which the body uses in the secondary response.

Question 29

Your sister-in-law never gets sick,while her male neighbour 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.

Question 30

In an ELISA test (enzyme-linked immunosorbent assay)what is the reason alkaline phosphatase is linked to the secondary antibody?

A)It ensures that contaminates from the medium are removed.
B)It can cause a color change to occur,indicating the presence of the specified antigen.
C)This enzyme is necessary to recognize the MHC found on infected cells.
D)All of the above answers apply.
E)Answers A and B both apply.

Question 31

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)all of the above
E)A and C only

Question 32

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)secondary cell

Question 33

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 34

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)One is activated by membrane bound antigens,while the other is activated by free-floating antigens in blood or lymph.
D)All of the above are differences.
E)Only A and B are differences.

Question 35

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 36

All of the following are differences between a B-cell receptor and an antibody produced by a B-cell except that

A)B-cell receptors belong to the immunoglobulin protein family while antibodies produced by B-cells do not.
B)B-cell receptors are inserted into the plasma membrane while antibodies produced by B-cells are secreted.
C)B-cells receptors have transmembrane domains while antibodies produced by B-cells do not.

Question 37

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 38

Which of the following is crucial to activation of the acquired 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)