Deck 1: Elements of the Immune System and Their Roles in Defense

Question 1

_____ cells persist long after an individual has been vaccinated.

A)Neutrophil
B)Plasma
C)Memory
D)M
E)Mast.

Answer 1

C

Question 2

Which of the following pairs is mismatched?

A)innate immunity: highly specialized defenses
B)secondary immune response: immunological memory
C)hematopoiesis: bone marrow
D)phagocytosis: uptake and killing of microbes
E)lymphocyte recirculation: continuous transport between blood and lymph.

Answer 2

A

Question 3

Name the parts of the body where epithelia act as barriers to infection.
B.Describe the three main ways in which epithelia carry out this barrier function,giving details of the mechanisms employed.

Answer 3

A.Skin; mucosal epithelium of the gastrointestinal tract; mucosal epithelium of the respiratory tract; mucosal epithelium of the urinogenital tract. B. (i)Mechanical (physical)barriers.Tight junctions between the epithelial cells prevent the penetration of pathogens between the cells to underlying tissues.In addition,there is a flow of air and fluid over epithelial surfaces,which oxygenates and flushes the surface,preventing anaerobic bacterial growth and transient adhesion.On ciliated epithelial surfaces,such as those of the respiratory tract,the formation of a layer of mucus that is kept in continual movement by the beating cilia inhibits colonization and invasion by microorganisms. (ii)Chemical barriers.The epithelium produces a variety of chemical substances that interfere with the adherence of microorganisms to epithelium and with their replication.The skin produces fatty acids in sebaceous glands,which helps to create an acid environment inhibitory to the growth of many bacteria.Lysozyme,an enzyme that inhibits cell-wall formation in bacteria,is secreted in tears,saliva,and sweat.The stomach produces strong hydrochloric acid,creating a highly acidic and formidable environment,which when combined with the stomach enzyme pepsin (an acid protease)poses one of the most inhospitable environments for microbial growth in our bodies.Defensins are antimicrobial peptides secreted by all the protective epithelia. (iii)Microbiological barriers.A microbiota of non-pathogenic commensal microorganisms colonizes many epithelial surfaces and provides an additional barrier to infection.They compete with pathogenic microbes for space and nutrients,and sometimes produce antibacterial proteins that further inhibit attachment to epithelium.For example,Escherichia coli in the large intestine produce colicins,which prevent colonization by other bacteria.

Question 4

first line of defense against microorganisms that infect the body is referred to as _____.

A)opportunistic immunity
B)innate immunity
C)adaptive immunity
D)primary immunity
E)central immunity.

Question 5

bacterium that causes a common disease in a population that has been previously exposed to it is called _____.

A)opportunistic
B)resistant
C)commensal
D)endemic
E)attenuated.

Question 6

_____ act as cellular messengers by delivering degraded pathogens to lymphoid organs.

A)Plasma cells
B)Dendritic cells
C)Large granular lymphocytes
D)Mast cells
E)Basophils.

Question 7

can antibiotics upset the barrier function of intestinal epithelia? Give a specific example.

Question 8

most cases,adaptive immune responses rely on the initial activation of _____ in secondary lymphoid tissue:

A)macrophages
B)T cells
C)B cells
D)dendritic cells
E)epithelium.

Question 9

Another name for a large granular lymphocyte is a _____.

A)plasma cell
B)helper T cell
C)monocyte
D)natural killer cell
E)eosinophil.

Question 10

Identify the incorrect statement regarding hematopoiesis.

A)Hematopoiesis is a continuous process that occurs throughout one's lifetime.
B)The location for hematopoiesis differs with age.
C)Self renewal is necessary to replenish the supply of hematopoietic stem cells.
D)Most hematopoiesis occurs in the bone marrow after birth.
E)Leukocytes,but not erythrocytes,must go through hematopoiesis in order to develop.

Question 11

thin layer of cells that makes up the interior lining of the blood vessels is called the _____.

A)mucosa
B)epithelium
C)endothelium
D)connective tissue
E)lymphoid tissue.

Question 12

of the following statements are characteristic of secondary immune responses except _____.

A)Secondary immune responses are activated when primary immune responses fail to completely eradicate an infection.
B)Secondary immune responses are restricted to adaptive immune responses.
C)Memory cells are activated rapidly during secondary immune responses.
D)Secondary immune responses are orders of magnitude greater than primary immune responses.
E)During a secondary immune response to a booster vaccine,it is possible to experience a primary immune response to an unrelated vaccine component encountered for the first time.

Question 13

_____ is (are)the lymphoid organ(s)that filter(s)the blood.

A)spleen
B)tonsils
C)Peyer's patches
D)appendix
E)adenoids.

Question 14

example of an antimicrobial peptide that protects epithelial surfaces from pathogens is _____.

A)glycoprotein
B)defensin
C)proteoglycan
D)lysozyme
E)sebum.

Question 15

Spherical regions in lymph nodes containing areas that are packed densely with proliferating B cells are called _____.

A)efferent vessels
B)germinal centers
C)red pulp zones
D)periarterial lymphoid sheaths
E)medullary sinuses.

Question 16

During an infection,_____ are mobilized in large numbers from the bone marrow.

A)dendritic cells
B)memory cells
C)macrophages
D)neutrophils
E)B cells.

Question 17

effector lymphocytes secrete _____,an inflammatory response ensues.

A)lysozyme
B)defensins
C)lymph
D)sebum
E)cytokines.

Question 18

last cases of smallpox were reported in the _____.

A)1950s
B)1960s
C)1970s
D)1980s
E)1990s.

Question 19

Identify the four classes of pathogens that provoke immune responses in our bodies and give an example of each.

Question 20

of the following are examples of chemical barriers of innate immunity except _____.

A)lactic acid
B)normal microbiota
C)lysozyme
D)fatty acids
E)proteases.

Question 21

Which of the following pairs is mismatched?

A)monocyte progenitor: macrophage
B)erythroid progenitor: megakaryocyte
C)myeloid progenitor: neutrophil
D)lymphoid progenitor: natural killer cell.
E)None of the above is mismatched.

Question 22

Examples of granulocytes include all of the following except:

A)neutrophil
B)monocyte
C)basophil
D)eosinophil.
E)All of the above are examples of granulocytes.

Question 23

term generally used to describe all white blood cells is _____.

A)hematopoietic cells
B)myeloid progenitor
C)dendritic cells
D)monocytes
E)leukocytes.

Question 24

Examples of pathogens that cause human disease include:

A)bacteria
B)viruses
C)fungi
D)parasites (protozoans and worms).
E)All of the above are examples of pathogens that cause human disease.

Question 25

Which of the following statements regarding neutrophils is false?

A)Neutrophils are mobilized from the bone marrow to sites of infection when needed.
B)Neutrophils are active only in aerobic conditions.
C)Neutrophils are phagocytic.
D)Neutrophils form pus,which comprises dead neutrophils.
E)Dead neutrophils are cleared from sites of infection by macrophages.

Question 26

Which of the following is not associated with mucosal surfaces?

A)mucus-secreting goblet cells
B)lysozyme
C)M cells
D)white pulp
E)beating cilia.

Question 27

Describe the characteristics commonly associated with inflammation and what causes them.

Question 28

Which of the following are characteristics of innate immunity:

A)inflammation
B)improvement in recognition of the pathogen during the response
C)fast response
D)highly specific for a particular pathogen
E)cytokine production.

Question 29

most abundant type of leukocyte in human peripheral blood is the _____.

A)eosinophil
B)basophil
C)neutrophil
D)monocyte
E)lymphocyte.

Question 30

Which of the following pairs is mismatched?

A)lymphocytes: innate immune response
B)natural killer cell: kills virus-infected cells
C)macrophage: phagocytosis and killing of microorganisms
D)erythrocyte: oxygen transport
E)eosinophil: defense against parasites.

Question 31

are clonal selection and clonal expansion in the context of an adaptive immune response? Describe how they shape the adaptive immune response.

Question 32

Phagocytosis of either microbes or microbial constituents by macrophages is followed by the activation of macrophages and the secretion of cytokines.What are the main effects of these molecules?

Question 33

Identify the two major progenitor subsets of leukocytes.
B.Where do they originate in adults?
C.Name the white blood cells that differentiate from these two progenitor lineages.

Question 34

Which of the following pairs of associations is mismatched?

A)large granular lymphocyte: T cell
B)megakaryocyte: platelet
C)B cell: plasma cell
C)monocyte: macrophage
D)myeloid progenitor: neutrophil.

Question 35

Which of the following statements are correct?

A)Macrophages are granulocytes.
B)Macrophages derive from monocytes.
C)Macrophages are non-phagocytic.
D)Macrophages reside in the tissues.
E)All of the above statements are false.

Question 36

Identify the different anatomical locations where hematopoiesis occurs in embryonic,fetal,and adult life.

Question 37

are the main differences between innate immunity and adaptive immunity?

Question 38

Primary lymphoid tissues are the sites where lymphocytes _______,whereas secondary lymphoid tissues are the sites where lymphocytes _______.

A)are stimulated; develop and mature
B)encounter pathogens; undergo apoptosis
C)develop and mature; become stimulated
D)undergo clonal selection; differentiate from hematopoietic stem cells
E)die; are phagocytosed after death.

Question 39

would be the consequence of a bioterrorist attack that released smallpox virus into a city?

Question 40

spleen differs from other secondary lymphoid organs in which of the following ways?

A)It does not contain T cells.
B)It filters blood as well as lymph.
C)It is populated by specialized cells called M cells.
D)It receives pathogens via afferent lymphatic vessels.
E)It has no connection with the lymphatics.

Question 41

Which of the following describes the flow of lymph through a lymph node draining an infected tissue?

A)efferent lymphatic vessel \rightarrow lymph node \rightarrow afferent lymphatic vessel
B)venule \rightarrow lymph node \rightarrow efferent lymphatic vessel
C)afferent lymphatic vessel \rightarrow lymph node \rightarrow efferent lymphatic vessel
D)artery \rightarrow lymph node \rightarrow efferent lymphatic vessel
E)afferent lymphatic vessel \rightarrow lymph node \rightarrow artery.

Question 42

Describe three distinct mechanisms by which antibodies eradicate infection.

Question 43

Which of the following is the predominant route by which pathogens are brought from a site of infection into a lymph node?

A)efferent lymphatics
B)artery
C)vein
D)afferent lymphatics
E)high endothelial venule.

Question 44

Vaccination is best described as prevention of severe disease by _______.

A)the deliberate introduction of a virulent strain of an infectious agent
B)prior exposure to an infectious agent in an attenuated or weakened form
C)prophylactic treatment with antibiotics
D)stimulating effective innate immune responses
E)using effective public-health isolation regimens such as quarantine.

Question 45

Which of the following statements is false?

A)During human development,hematopoiesis takes place at different anatomical locations.
B)The hematopoietic stem cell gives rise to white blood cells,but a different stem cell is the progenitor of red blood cells.
C)Hematopoietic stem cells are self-renewing.
D)Platelets participate in clotting reactions to prevent blood loss.
E)Megakaryocytes do not circulate and reside only in the bone marrow.

Question 46

does it take approximately a week after infection for the benefits of an adaptive immune response to start to be felt?

Question 47

Which of the following explains why immunity to influenza may appear to be relatively short-lived?

A)Effective immunological memory fails to develop.
B)Immune responses to influenza involve innate immune mechanisms only.
C)The primary and secondary immune responses are equivalent.
D)Influenza virus targets memory cells.
E)New influenza variants able to escape previous immunity appear regularly.
ANSWERS

Question 48

Immune cells within the lymphatic circulation are directly deposited into which of the following anatomical sites so that the cells may reenter the bloodstream?

A)right aorta
B)left subclavian vein
C)left carotid artery
D)high endothelial venule
E)hepatic vein.