KIN 224 Ch. 22

smaller; nucleic acid within a protein capsid.

A virus is ______ than a bacterial cell, and a virus is composed of a _________________.

b

Malaria is a disease caused by a

a: multicellular parasite.

b: protozoan.

c: fungus.

d: virus.

e: bacterium.

a

Fungi are

a: eukaryotic cells with a cell wall.

b: prokaryotic cells.

c: multicellular parasites that reside within a host.

d: protozoans lacking a cell wall.

e: viruses that are fragments of infectious proteins.

c

"Mad cow disease" (variant Creutzfeldt-Jakob disease) is caused by a

a: fungus.

b: protozoan.

c: prion.

d: virus.

e: bacterium.

b

Consuming meat that has been infected with a prion can lead to the disease

a: trichomoniasis.

b: bovine spongiform encephalopathy.

c: clostridium tetani.

d: histoplasmosis.

d

Dendritic cells of the skin are derived from

a: macrophages.

b: B-lymphocytes.

c: T-lymphocytes.

d: monocytes.

e: neutrophils.

mast cells

Which cells resemble basophils and are found in connective tissue, close to small blood vessels?

proteins; chemical messengers

In terms of their chemical structure, cytokines are _; their function is to serve as ___.

d

Cytokines have a _____ half-life and exert influence on ________________.

a: long; immune cells only.

b: long; immune and non-immune cells.

c: short; immune cells only.

d: short; immune and non-immune cells.

a

When a chemical messenger has a short half-life, it means that

a: it will not have an extremely prolonged effect on target cells.

b: it will not be eliminated quickly from the blood.

b

Interferons are one of the classes of

a: interleukins.

b: cytokines.

c: colony-stimulating factors.

d: tumor necrosis factors.

b

Which class of chemical messenger facilitates white blood cell formation in bone marrow?

a: Interleukins

b: Colony-stimulating factors

c: Tumor necrosis factors

d: Interferons

a

A delayed response to a specific antigen is provided by

a: adaptive immunity.

b: innate immunity.

c: inflammation.

b

Nonspecific immunity is another name for

a: adaptive immunity.

b: innate immunity.

c: cell-mediated immunity.

d: acquired immunity.

d

Defensins and lysosomes are both part of ________ immunity and function as ___________.

a: adaptive; physical barriers to pathogen entry

b: adaptive; attackers of pathogenic cells

c: innate; physical barriers to pathogen entry

d: innate; attackers of pathogenic cells

b

Which of the following lists the body's first, second, and third lines of defense in order?

a: Adaptive immunity, external innate immunity, internal immunity

b: External innate immunity, internal innate immunity, adaptive immunity

c: External innate immunity, adaptive immunity, internal innate immunity

d: External adaptive immunity, internal adaptive immunity, innate immunity

e: Innate immunity, internal adaptive immunity, internal innate immunity

c

If someone had a cut in their skin through which a bacterium entered, but that bacterium was then destroyed by a neutrophil, this would be an example of

a: failed external adaptive immunity, but successful innate immunity.

b: failed innate immunity, but successful adaptive immunity.

c: failed external innate immunity, but successful internal innate immunity.

d: failed external immunity, but successful internal acquired immunity.

b

Which type of cell is the most effective to attack multicellular parasites such as tapeworms?

a: Basophils

b: Eosinophils

c: Macrophages

d: Neutrophils

natural killer cells

Which type of cell attacks a variety of unwanted cells and causes those cells to undergo apoptosis?

interferon

Often a virus-infected cell will release _________ to prevent spread of the infection.

c

Which is not an action of interferon?

a: It stimulates macrophages and NK cells to destroy virus-infected cells.

b: It triggers synthesis of enzymes that destroy viral nucleic acids.

c: It signals the immune system that the secreting cell is part of the body and so should not be attacked.

d: It binds to receptors of neighboring cells preventing them from being infected.

c

"Complement" refers to a group of

a: white blood cells.

b: antibodies.

c: plasma proteins.

d: molecules on the surface of pathogenic microbes.

b

In the classical pathway of complement activation,

a: complement is activated within liver cells and released into the blood.

b: complement binds to an antibody that is bound to a foreign substance.

c: complement binds with polysaccharides on a microbial cell wall.

d: complement inhibits inflammation and binds to opsonins.

b

A membrane attack complex is a protein grouping that

a: triggers phagocytosis of a target cell by a nearby macrophage or neutrophil.

b: forms a channel in the target cell membrane that causes cytolysis.

c: links a pathogen to a red blood cell so that it is carried to the liver or spleen.

d: stimulates basophils to attack a multicellular parasite in the body.

d

Inflammation is a(n)

a: antigen-specific process that occurs in avascular tissue.

b: antigen-specific process that occurs in vascularized tissue.

c: nonspecific process that occurs in avascular tissue.

d: nonspecific process that occurs in vascularized tissue.

b

Chemotaxis is the process by which

a: CAMs on leukocytes adhere to CAMs on endothelial cells of capillaries within injured tissues.

b: cells migrate along chemical gradients.

c: cells exit the blood by squeezing out between cells in the blood vessel wall.

d: chemical messengers are secreted that stimulate the sensation of pain that accompanies inflammation.

d

Exudate is

a: blood that escapes capillaries, passes beyond the skin and leaves the body.

b: increased perfusion of capillary beds within the region of an injury.

c: lymph that flows away from the heart and toward the site of an injury.

d: fluid that leaves capillaries to "wash" the interstitial space of an injured tissue.

e: clotting proteins that wall off microbes and prevent them from spreading through the bloodstream.

d

Which is not one of the cardinal signs of inflammation?

a: Heat

b: Redness

c: Loss of function

d: Numbness

e: Swelling

a

Inflamed tissue feels warm due to

a: increased blood flow and increased metabolic activity.

b: the margination of white blood cells.

c: chemotaxis and defervescence.

d: activation of complement by binding of C-reactive protein to bacterial carbohydrates.

c

Interleukin 1 and interferons act as

a: defervescents and trigger an elevation of body temperature.

b: defervescents and trigger a decrease of body temperature.

c: pyrogens and trigger an elevation of body temperature.

d: pyrogens and trigger a decrease of body temperature.

c

Pyrogens act on the __________ of the brain where they cause release of ________.

a: hippocampus; PGE2

b: hippocampus; exudate

c: hypothalamus; PGE2

d: hypothalamus; exudate

inhibits, increases

A fever _(inhibits/increases) reproduction of bacteria and __ (increases/inhibits) CAMs on the endothelium of capillaries of lymph nodes.

b

Antigens are

a: something made by a white blood cell to destroy a pathogen.

b: something that an antibody or T-lymphocyte binds to.

c: disorders involving overactive immune systems.

d: membrane receptors on B-lymphocytes.

c

Which type of antigen would have the greatest immunogenicity?

a: One that is small, simple, familiar, and abundant

b: One that is small but complex and rare

c: One that is large, complex, foreign, and abundant

d: One that is large but simple and familiar

d

Poison ivy contains a toxin that acts as a hapten by

a: raising the body's sensitivity to a wide variety of chemicals such as penicillin.

b: cutting plasma protein antibodies in half.

c: preventing effective immune responses by blocking release of bradykinin.

d: combining with a body protein and then triggering an immune response.

c

Helper T-lymphocytes are also known as

a: cytotoxic T-lymphocytes.

b: CD8+ cells.

c: CD4+ cells.

d: T8 cells.

e: memory T-lymphocytes.

a

Which type of lymphocyte has coreceptors that assist in the interaction of the lymphocyte with a cell presenting antigen?

a: T-lymphocyte

b: B-lymphocyte

d

Antigen presentation involves the display of an antigen

a: inside the cytoplasm of a B-lymphocyte.

b: on the surface of a cell so that a B-lymphocyte can be exposed to it.

c: inside the cytoplasm of a T-lymphocyte.

d: on the surface of a cell so that a T-lymphocyte can be exposed to it.

b

Antigen-presenting cells are _, and they display antigens to both _ and ______________.

a: immune cells; B-lymphocytes; T-lymphocytes

b: immune cells; helper T-lymphocytes; cytotoxic T-lymphocytes

c: any nucleated cell; B-lymphocytes; T-lymphocytes

d: any anucleate cell; helper T-lymphocytes; cytotoxic T-lymphocytes

e: any blood cell; helper B-lymphocytes; cytotoxic B-lymphocytes

b

Which class of major histocompatibility molecules is specific to antigen-presenting cells?

a: MHC class I

b: MHC class II

b

MHC class I molecules are

a: glycolipid synthesized on the smooth endoplasmic reticulum.

b: glycoproteins synthesized on the rough endoplasmic reticulum.

c: small peptides synthesized on free ribosomes.

d: phospholipids synthesized in secretory vesicles.

d

MHC class I molecules present peptide fragments that are either "self" or "nonself"; in either case, the fragment becomes bound to the molecule while

a: in the Golgi apparatus.

b: in the cytosol.

c: in a secretory vesicle.

d: in the rough endoplasmic reticulum.

b

MHC class I molecules on a cell allow it to interact with

a: natural killer cells.

b: cytotoxic T-lymphocytes.

c: helper T-lymphocytes.

d: CD8+ B-lymphocytes.

b

Activation of lymphocytes occurs in

a: primary lymphatic structures.

b: secondary lymphatic structures.

c: tertiary lymphatic structures.

d: effectors such as muscles and glands.

b

The site of infection is the location at which lymphocytes

a: are formed.

b: provide an effector response.

c: are activated.

d: become able to recognize one specific foreign antigen.

c

When they leave the red marrow, pre-T-lymphocytes have

a: only the CD4 protein.

b: only the CD8 protein.

c: both the CD4 and CD8 proteins.

d: neither the CD4 nor CD8 protein.

e: either the CD4 or CD8 protein.

b

In positive selection of T-lymphocytes, those cells that

a: bind self antigens are eliminated.

b: can bind MHC survive.

c: bind to self antigens survive.

d: bind to MHC class II are eliminated.

a

If T-lymphocytes that failed the negative selection test were not destroyed, the immune system would likely

a: cause autoimmune disorders.

b: exhibit very delayed activity.

c: be unable to recognize a particular class of pathogen.

d: exhibit more negative membrane potentials.

b

As T-lymphocytes leave the thymus, they are

a: naive and not yet competent.

b: naive and immunocompetent.

c: activated but not yet competent.

d: activated and immunocompetent.

d

The first signal during helper T-lymphocyte activation involves

a: BCR of the helper T-cell binding with free antigen and engulfing it.

b: CD8 of the helper T-cell binding with MHC class III of the antigen-presenting cell.

c: CD4 of the helper T-cell binding with MHC class I part of the antigen fragment.

d: CD4 of the helper T-cell binding with MHC class II of the antigen-presenting cell.

c

Upon activation, a T-lymphocyte

a: ceases dividing and becomes a plasma cell.

b: ceases dividing and becomes a memory cytotoxic helper cell.

c: proliferates to form clones and memory cells.

d: proliferates to form B cells and plasma cells.

b

The second signal during B-lymphocyte activation involves stimulation from

a: IL-2 released by cytotoxic T-lymphocytes.

b: IL-4 released by helper T-lymphocytes.

c: bradykinin released by antigen-presenting cells.

d: antibodies released by antigens.

c

Most activated B-lymphocytes differentiate into

a: memory helper T-lymphocytes.

b: macrophages.

c: plasma cells.

d: antigen-presenting cells.

c

Cytotoxic T-lymphocytes destroy infected cells by releasing

a: antibodies.

b: bradykinin and histamine.

c: perforin and granzymes.

d: CD4+.

a

Cytotoxic T-lymphocytes destroy infected cells by

a: increasing the permeability of infected cells and inducing apoptosis.

b: increasing the permeability of infected cells and preventing apoptosis.

c: decreasing the permeability of infected cells and inducing apoptosis.

d: decreasing the permeability of infected cells and preventing apoptosis.

b

Why are functions of T-lymphocytes referred to as "cell-mediated" immunity?

a: Because T-lymphocytes are cells and not just plasma proteins

b: Because T-lymphocytes work against antigens associated with cells

c: Because T-lymphocytes work only against single-celled infectious agents

d: Because T-lymphocytes must activate other classes of cells in order to have any effect

c

What are considered the effectors of humoral immunity?

a: Helper T-lymphocytes

b: Cytotoxic T-lymphocytes

c: Antibodies

d: Macrophages

e: Natural killer cells

b

Plasma cells have a life span of about _, which is mainly spent in the _.

a: 5 days; blood

b: 5 days; lymph nodes

c: 130 days; blood

d: 130 days; lymph nodes

b

An immunoglobulin is a(n)

a: antibody, which is a white blood cell.

b: antibody, which is a protein molecule.

c: lymphocyte, which is a white blood cell.

d: lymphocyte, which is a protein molecule.

e: antigen, which is a cell receptor.

d

Which part of an antibody attaches to an antigen?

a: The hinge region

b: The constant region

c: The heavy chain

d: The variable region

a

The clumping of foreign cells that occurs when antibodies cross-link their antigens is known as

a: agglutination.

b: neutralization.

c: precipitation.

d: opsonization.

e: fixation.

b

Opsonization involves

a: cross-linking several antigens together so that they are no longer soluble, and it is facilitated by the Fc region of the antibody.

b: marking a target for phagocytosis, and it is facilitated by interaction of the Fc region of the antibody with a phagocyte.

c: activation of NK cells, and it is a function of the antigen-binding site of the antibody.

d: fixation of antibodies in the IgG and IgM classes, and it involves the antigen-binding site of the antibody.

e

What are the five main classes of immunoglobulins found in humans?

a: IgA, IgC, IgE, IgG, IgI

b: IgD, IgE, IgG, IgM, IgS

c: IgB, IgD, IgE, IgG, IgM

d: IgA, IgB, IgC, IgD, IgE

e: IgA, IgD, IgE, IgG, IgM

IgG

The most prevalent antibody in blood and lymph is

IgE

Which type of antibody is formed in response to parasitic infections and allergies, and has the effect of activating mast cells and basophils?

b

IgA is primarily found

a: in blood.

b: in external secretions such as tears, saliva, and mucus.

c: in lymph.

d: on the surface of B-lymphocytes.

e: in the thymus, spleen, and lymph nodes.

d

Agglutination of mismatched blood is a function of

a: IgD, which is a dimer.

b: IgD, which is a pentamer.

c: IgM, which is a dimer.

d: IgM, which is a pentamer.

b

The secondary response of the immune system to an infectious agent involves

a: fewer cells than the antigen challenge, as the response has become more specific.

b: more cells than the antigen challenge, due to the proliferation of memory cells.

c: amnesia of past exposures, so that a perfectly adapted response can be generated to the new pathogen.

c

Vaccines are effective because they

a: immediately stimulate cellular immunity to eliminate all of the pathogen in the body.

b: inhibit antibodies from having secondary responses.

c: stimulate the development of immunologic memory.

d: increase the number of natural killer cells while decreasing the numbers of T and B cells.

shorter

A secondary response to an infectious agent has a _______ latent phase than a primary response has.

a

When compared to a primary response, the antibody levels in a secondary response

a: rise more rapidly and with a greater proportion of IgG antibodies.

b: rise more rapidly and with a smaller proportion of IgG antibodies.

c: rise more gradually and with a greater proportion of IgG antibodies.

d: rise more gradually and with a smaller proportion of IgG antibodies.

active

The immunity that occurs as a result of a vaccination is _________ immunity.

b

Immunity can be transferred from mother to child. When the child's immunity is acquired

a: through the placenta, it is passive immunity, but through breastmilk it is active immunity.

b: through the placenta or through breastmilk, it is passive immunity.

c: through the placenta or through breastmilk, it is active immunity.

d: through the placenta, it is active immunity, but through the breastmilk it is passive immunity.

b

Active immunity requires

a: the transfer of antibodies from another individual.

b: direct encounter with the antigen.

c: that an active virus be used in a vaccine.

d: that all immune responses to the pathogen result in symptoms of illness.

b

Passive immunity lasts

a: from days to weeks, and involves development of memory cells.

b: from days to weeks, and does not involve development of memory cells.

c: from years to a lifetime, and involves the development of memory cells.

d: from years to a lifetime, and does not involve development of memory cells.

a

The function of helper T-lymphocytes is to

a: initiate and oversee the immune response.

b: turn off the immune response once it has been activated.

c: secrete toxins to kill or disable pathogens.

d:trigger cell death by disrupting metabolic activities.

e: All choices are correct.

e

Once a helper T-lymphocyte recognizes an antigen, it begins the immune response by secreting chemical signals called

a: antibodies.

b: immunoglobulins.

c: memory B-lymphocytes.

d: memory T-lymphocytes.

e: cytokines.

c

A variety of lymphatic cells are involved in the immune response. Which is not part of the process?

a: Production of antibodies

b: Direct attack and destruction of foreign or abnormal agents

c: Replication of antigens

d: Formation of memory cells

c

Which type of cell responds to multiple antigens?

a: Memory B-lymphocyte

b: Memory T-lymphocyte

c: Natural killer cell

d: Plasma cell

e: Cytotoxic T-lymphocyte

d

Which type of cell produces and secretes antibodies?

a: Memory B-lymphocyte

b: Memory T-lymphocyte

c: Natural killer cell

d: Plasma cell

e: Cytotoxic T-lymphocyte

e

Cytotoxic T-lymphocytes that have killed a foreign cell may transform into

a: memory B-lymphocytes.

b: natural killer cells.

c: plasma cells.

d: helper T-lymphocytes.

e: None of the choices is correct.

c

Which cell type is targeted by the human immunodeficiency virus (HIV)?

a: Cytotoxic T-lymphocyte

b: Memory B-lymphocyte

c: Helper T-lymphocyte

d: Natural killer cell

e: Plasma cell

a

The primary goal of the immune response is

a: destruction or inactivation of pathogens and foreign material.

b: maintenance of the proper ionic balance between lymph and blood.

c: stimulation of mitotic activity in order to replace cells damaged by infection.

d: reduction of the number of circulating memory lymphocytes.

e: removal of antibodies from lymph and lymphatic organs.