Question 1

In which situation would helper T cells be activated?

Accepted Answer

A) when an antigen is displayed by a dendritic cell 
B) when a cytotoxic T cell releases cytokines 
C) when natural killer (NK)cells come in contact with a tumor cell 
D) when B cells respond to T-independent antigens 
A) when an antigen is displayed by a dendritic cell 
B) when a cytotoxic T cell releases cytokines 
C) when natural killer (NK)cells come in contact with a tumor cell 
D) when B cells respond to T-independent antigens

Question 2

A patient complaining of watery,itchy eyes and sneezing after being given a flower bouquet as a birthday gift should first be treated with

Accepted Answer

A) a vaccine. 
B) complement. 
C) antihistamines. 
D) monoclonal antibodies. 
A) a vaccine. 
B) complement. 
C) antihistamines. 
D) monoclonal antibodies.

Question 3

Juan is a 5-year-old boy and recently recovered from the chickenpox.He returned to kindergarten and found out that his friend Tram had chickenpox too.Normally chickenpox is very infectious,but Juan did not acquire it again.Why was Juan protected from a second exposure to chickenpox?

Accepted Answer

A) because his immune system now has immunological memory 
B) because his innate immune system was strengthened 
C) because his inflammatory response was conditioned for chickenpox 
D) because his immune system underwent antigenic variation 
A) because his immune system now has immunological memory 
B) because his innate immune system was strengthened 
C) because his inflammatory response was conditioned for chickenpox 
D) because his immune system underwent antigenic variation

Question 4

An epitope is

Accepted Answer

A) part of the interferons that penetrate foreign cells. 
B) a protein protruding from the surface of B cells. 
C) an antibody that is dissolved in blood plasma. 
D) the part of an antigen that binds to an antigen receptor. 
A) part of the interferons that penetrate foreign cells. 
B) a protein protruding from the surface of B cells. 
C) an antibody that is dissolved in blood plasma. 
D) the part of an antigen that binds to an antigen receptor.

Question 5

An inflammation-causing signal released by mast cells at the site of an infection is (are)

Accepted Answer

A) interferons. 
B) lymph. 
C) histamine. 
D) mucus. 
E) antibodies. 
A) interferons. 
B) lymph. 
C) histamine. 
D) mucus. 
E) antibodies.

Question 6

Fruit flies normally produce two types of antimicrobial peptides (defensin and drosomycin).Mutant fruit flies were generated that produced no antimicrobial peptides,defensin only,or drosomycin only.Wild-type flies and the mutant flies were then tested for survival after infection with Neurospora crassa fungi.What statement about these data is true?

Accepted Answer

A) No wild-type fruit flies die after being infected by the fungi. 
B) Drosomycin protects fruit flies from N.crassi infections to a higher degree than does defensin. 
C) Defensin is effective at preventing fruit fly infection by all fungal species. 
D) After two days,approximately 65% of mutant + defensin fruit flies are dead. 
A) No wild-type fruit flies die after being infected by the fungi. 
B) Drosomycin protects fruit flies from N.crassi infections to a higher degree than does defensin. 
C) Defensin is effective at preventing fruit fly infection by all fungal species. 
D) After two days,approximately 65% of mutant + defensin fruit flies are dead.

Question 7

The complement system is a

Accepted Answer

A) set of proteins involved in innate but not acquired immunity. 
B) set of proteins secreted by cytotoxic T cells and other CD8 cells. 
C) group of proteins that includes interferons. 
D) group of antimicrobial proteins that act together in a cascading manner. 
E) set of proteins that act individually to attack and lyse microbes. 
A) set of proteins involved in innate but not acquired immunity. 
B) set of proteins secreted by cytotoxic T cells and other CD8 cells. 
C) group of proteins that includes interferons. 
D) group of antimicrobial proteins that act together in a cascading manner. 
E) set of proteins that act individually to attack and lyse microbes.

Question 8

Cave art by early humans recognized the existence of the major signs of inflammation.The most inclusive set of symptoms of inflammation that might appear in such early human art is

Accepted Answer

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. 
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 9

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

Accepted Answer

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. 
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 10

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

Accepted Answer

A) lysozyme production. 
B) phagocytosis by neutrophils. 
C) antibody production by plasma cells. 
D) histamine release by basophils. 
E) conversion of helper T cells to memory helper T cells. 
A) lysozyme production. 
B) phagocytosis by neutrophils. 
C) antibody production by plasma cells. 
D) histamine release by basophils. 
E) conversion of helper T cells to memory helper T cells.

Question 11

Arrange these components of the mammalian immune system as it first responds to a pathogen in the correct sequence.
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.

Accepted Answer

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 
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 12

Mammals have Toll-like receptors (TLRs)that can recognize a kind of macromolecule that is absent from vertebrates but present in/on certain groups of pathogens,including viral

Accepted Answer

A) lipopolysaccharides. 
B) double-stranded DNA. 
C) double-stranded RNA. 
D) glycoproteins. 
E) phospholipids. 
A) lipopolysaccharides. 
B) double-stranded DNA. 
C) double-stranded RNA. 
D) glycoproteins. 
E) phospholipids.

Question 13

Which of these is not part of insect immunity?

Accepted Answer

A) antibacterial digestive enzymes 
B) activation of natural killer cells 
C) phagocytosis by hemocytes 
D) production of antimicrobial peptides 
A) antibacterial digestive enzymes 
B) activation of natural killer cells 
C) phagocytosis by hemocytes 
D) production of antimicrobial peptides

Question 14

Normal immune responses can be described as polyclonal because

Accepted Answer

A) blood contains many different antibodies and antigens. 
B) multiple immunoglobulins are produced from descendants of a single B cell. 
C) diverse antibodies are produced for different epitopes of a specific antigen. 
D) macrophages,T cells,and B cells all are involved in a normal immune response. 
A) blood contains many different antibodies and antigens. 
B) multiple immunoglobulins are produced from descendants of a single B cell. 
C) diverse antibodies are produced for different epitopes of a specific antigen. 
D) macrophages,T cells,and B cells all are involved in a normal immune response.

Question 15

A mutation in the gene for CD4 leads to the production of nonfunctioning CD4 proteins in the plasma membrane of a helper T cell.What role would the helper T cell be unable to perform?

Accepted Answer

A) response to T-independent antigens 
B) lysing tumor cells 
C) stimulating a cytotoxic T cell 
D) interacting with a class I MHC-antigen complex 
E) interacting with a class II MHC-antigen complex 
A) response to T-independent antigens 
B) lysing tumor cells 
C) stimulating a cytotoxic T cell 
D) interacting with a class I MHC-antigen complex 
E) interacting with a class II MHC-antigen complex

Question 16

Through the evolution of antigenic variation,pathogens are able to

Accepted Answer

A) change the epitopes they express to elude a secondary immune response. 
B) change their genome to elude a secondary immune response. 
C) change the types of RNAs they express to elude a secondary immune response. 
D) change their size to elude a secondary immune response. 
A) change the epitopes they express to elude a secondary immune response. 
B) change their genome to elude a secondary immune response. 
C) change the types of RNAs they express to elude a secondary immune response. 
D) change their size to elude a secondary immune response.

Exam 35: The Immune System

In which situation would helper T cells be activated?

A patient complaining of watery,itchy eyes and sneezing after being given a flower bouquet as a birthday gift should first be treated with

Juan is a 5-year-old boy and recently recovered from the chickenpox.He returned to kindergarten and found out that his friend Tram had chickenpox too.Normally chickenpox is very infectious,but Juan did not acquire it again.Why was Juan protected from a second exposure to chickenpox?

An epitope is

An inflammation-causing signal released by mast cells at the site of an infection is (are)

The complement system is a

Cave art by early humans recognized the existence of the major signs of inflammation.The most inclusive set of symptoms of inflammation that might appear in such early human art is

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

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

Mammals have Toll-like receptors (TLRs)that can recognize a kind of macromolecule that is absent from vertebrates but present in/on certain groups of pathogens,including viral

Which of these is not part of insect immunity?

Normal immune responses can be described as polyclonal because

A mutation in the gene for CD4 leads to the production of nonfunctioning CD4 proteins in the plasma membrane of a helper T cell.What role would the helper T cell be unable to perform?

Through the evolution of antigenic variation,pathogens are able to

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Carbon and the Molecular Diversity of Life

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Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development,stem Cells,and Cancer

Viruses

Genomes and Their Evolution

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