Chapter 21 Mastering Questions

Which of the following is not a chemical barrier that helps prevent infections? A. Urine B. Mucus C. Tears D. The pH of the blood

Which of the following provides a first line of defense against pathogens? A. Antimicrobial proteins B. Inflammation C. Complement D. Intact skin and mucous membranes

With what does our immune system coat pathogens to facilitate their capture and accelerate phagocytosis? A. Mucin B. Opsonins C. Histamine D. Defensins

What type of immune system cell performs the most phagocytosis in the body? A. B lymphocytes B. Natural killer, or NK, cells C. Neutrophils D. Machrophages

Which of the following inflammatory chemicals is/are released by mast cells? A. Complement B. Prostaglandins C. Kinins D. Histamine

Which of the following is not one of the effects produced by the release of inflammatory chemicals? A. Vasoconstriction B. Attraction of neutrophils C. Increased access of clotting chemicals D. Redness

When do neutrophils enter the blood from the red bone marrow in response to leukocytosis-inducing factors? A. During chemotaxis B. During margination C. During leukocytosis D. During diapedesis

What characterizes the chemotaxis phase of phagocyte mobilization? A. Neutrophils actively ingest bacteria B. Neutrophils flatten to squeeze between the endothelial cells of the capillary walls C. Neutrophils cling to the inner walls of capillaries and postcapillary venules D. Neutrophils and other WBCs migrate up the gradient of chemotactic agents to the site of injury

What characterizes the diapedesis phase of phagocyte mobilization? A. Chemotaxis B. Margination C. Leukocytosis D. Neutrophils flatten to squeeze between the endothelial cells of the capillary walls

What protein can be released by infected cells to help protect cells that have not yet been infected? A. Complement B. Pyrogens C. Interferon D. Opsonins

(T/F) Discharge is one of the cardinal signs of inflammation

Which type of chemical induces fever? A. Complement B. Interferon C. Antibodies D. Pyrogens

Which of the following is an effect on complement activation? A. Tissue repair B. T cell activation C. Opsonization D. Fever

Which cells secrete histamines that trigger inflammatory pathways? A. Macrophages B. NK cells C. Mast cells D. Neutrophils

When the white blood cell count is depressed, the classic signs of infection such as redness, local heat, and swelling are not manifested. In this case, should the nurse avoid administering aspirin? A. No, aspirin can be used because the infection is still occurring even if the signs are not showing B. No, aspirin can still be used to treat the pain C. Yes, aspirin should be avoided because aspirin would disguise a fever that would indicate infection D. Yes, aspirin should be avoided because it would prevent the remaining white blood cells from responding to the infection

Which of the following does not describe actions of interferon (IFN)? A. IFN will attract macrophages to the secreting cell to be removed by phagocytosis? B. Virally infected cells can release interferon which attracts NK cells to attach and kill the IFN secreting cell. C. IFN can penetrate the viral capsid and destroy the virus D. IFN binds to normal, uninfected cells stimulating the activation of genes that produce anti-viral proteins

Membrane attack complex (MAC) kills by A. Disrupting the selectively permeability of a bacteria's plasma membrane B. Penetrating the capsule of the bacteria giving antibiotic drugs access to bacterial cells C. Allowing the organelles to spill free from the bacteria D. Providing a passage for antibodies to enter into the bacterial cytosol

All but one of the following occur during the inflammatory response. Select the example below that does not describe the process of inflammation A. Vasoconstriction will prevent excessive blood loss due to injury B. Chemotaxis draws leukocytes to the site of injury C. Increases capillary permeability D. Release of prostaglandins resulting in pain

Interferons A. Are virus-specific, so that an interferon produced against one virus could not protect cells against another virus B. Interfere with viral replication within cells C. Are routinely used in nasal sprays for the common cold D. Act by increasing the rate of cell division

Activated T cell and macrophages release (?) to mobilize immune cells and attract other leukocytes into the area A. Perforins B. Cytokines C. Interleukin 2 proteins D. Interleukin 1 proteins

Which of the following is a part of the second line of defense against microorganisms? A. Phagocytes B. Gastric juice C. Keratin D. Cilia

Cancer cells and virus-infected body cells can be killed before activation of adaptive immunity by A. T lymphocytes B. Natural killer cells C. Pinocytosis D. B lymphocytes

Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed A. Diapedesis B. Opsonization C. Agglutination D. Chemotaxis

Innate immune system defenses include A. Phagocytosis B. B cells C. Plasma cells D. T cells

Fever A. Decreases the metabolic rate of the body to conserve energy B. Causes the liver to release large amounts of iron, which seems to inhibit bacterial replication C. Is a higher-than-normal body temperature that is always dangerous D. Production is regulated by chemicals that reset the body's thermostat to a higher setting

What is the role of interferon in defense against disease? A. Activates the inflammatory process B. Activates the complement mechanism C. To kill the bacteria D. Protects cells that have not yet been infected by viruses

(T/F) Dendritic cells and macrophages kill by ingestion and destruction of particulate matter in a process called phagocytosis

(T/F) The directional movement of cells in response to chemicals is called chemotaxis

Slows or stops the immune response A. Regulatory T cell B. Memory cell C. Cytotoxic T cell D. B cell E. Helper T cell

Enables quick and efficient response to secondary exposure to antigen A. Regulatory T cell B. Memory cell C. Cytotoxic T cell D. B cell E. Helper T cell

Kills cancer cells and virus infected body cells A. Regulatory T cell B. Memory cell C. Cytotoxic T cell D. B cell E. Helper T cell

Forms antibody producing cells A. Regulatory T cell B. Memory cell C. Cytotoxic T cell D. B cell E. Helper T cell

Absence results in no immune response A. Regulatory T cell B. Memory cell C. Cytotoxic T cell D. B cell E. Helper T cell

(T/F) Some immunocompetent cells will never encounter an antigen to which they can bind and therefore will never be called to service in our lifetime

Which of the areas seen the figure must be occupied by T lymphocytes, at least for a while, but is NOT required for the production of B lymphocytes? A. The bone marrow B. The general circulation C. The thymus D. Lymph nodes

Proliferation of lymphocytes occurs immediately after A. Entering the circulation B. Activation C. Seeding of secondary lymphoid organs D. Release from the bone marrow

Without the positive selection process in lymphocyte maturation A. NK cells would be non-functional B. T-cells would not be able to properly bind to APC's and therefore not be activated by them C. Autoimmune diseases would be likely to result D. Monocytes would not be able to migrate into infected tissue and differentiate into macrophages

B lymphocytes develop immunocompetence in the A. Bone marrow B. Thymus C. Lymph nodes D. Spleen

Which of the following cells engulf antigens and present fragments on them on their own surfaces for recognition? A. T lymphocytes B. Plasma cells C. Dendritic cells D. NK cells

(T/F) The nucleotide sequence within the genes that produce B cell receptor and antibodies are reshuffled by a process called somatic recombination. This produces the huge variability in antibody types.

The antivenom used to treat venomous snake bites is an antibody produced in an animal such as a horse. Suppose these antibodies are injected into a patient who has been bitten by a venomous snake--how would you classify the resulting humoral immunity? A. Passive immunity, naturally acquired B. Passive immunity, artificially acquired C. Active immunity, naturally acquired D. Active immunity, artificially acquired

Which of the following best illustrates artificially acquired active humoral immunity? A. Antibodies received in breast milk B. Antivenoms C. Infection D. Vaccines

Which of the following occurs when antibodies block specific sites on viruses or bacterial exotoxins? A. Agglutination B. Complement fixation and activation C. Precipitation D. Neutralization

Which mechanism(s) of antibody action result(s) in cell lysis? A. Complement fixation and activation B. Agglutination C. Precipitation D. Neutralization

Which of the following statements regarding the primary versus the secondary immune response is true? A. The antibodies produced in a primary response bind to antigens more efficiently than the antibodies produced in a secondary immune response B. A primary response occurs faster than a secondary response C. A primary response results when naive lymphocytes are activated, while a secondary response is a result of activating memory cells D. A primary response leads to higher levels of antibodies than does a secondary response

Vaccines provide what type of immunity? A. Artificial passive B. Natural active C. Artificial active D. Natural passive

A vaccine is effective because A. The vaccine contains the antibodies necessary to fight infection B. B-lymphocytes are unable to mount an immune response the first time they are exposed to a new pathogen C. The secondary response of the adaptive immunity is faster and more efficient the primary response D. The vaccine contains the lymphocytes necessary to fight infection

A flu vaccine is needed seasonally to be effective but a polio vaccine is only needed once. The best explanation of this is A. Exposure to flu vaccine produces no memory cells from proliferating B-lymphocytes B. The polio virus is substantially weaker than the flu virus C. The flu vaccine is substantially weaker than the polio vaccine D. The flu has several strains that changes seasonally

In clonal selection of B cells, which substance is responsible for determining which cells will eventually become cloned? A. Complement B. Antibody C. Antigen D. Interferon

The primary immune response A. Has a lag period while B cells proliferate and differentiate into plasma cells B. Occurs more rapidly and is stronger than the secondary response C. Occurs when memory cells are stimulated D. Is another name for immunological memory

Antibody function include all of the following except A. Linking soluble antigens together so that they fall out of solution B. Binding and inactivating chemical toxins released by bacteria or other microorganisms C. Cross-linking cell-bound antigens on red blood cells when blood types are properly matched D. Targeting foreign cells so that complement proteins can cause cellular lysis

Why are children given vaccinations? A. So that they will develop a mild case of a disease in order to prevent a more serious case of the disease later on B. In order to activate the cell-mediated defense against pathogens C. In order to see whether the immune system is capable of defense against disease D. So that they will develop antibodies against various disease

Which of the following statements does not describe the adaptive immune response? A. It is systemic B. It is specific C. It occurs immediately after the body is challenged by foreign material D. It has memory

Health workers working with diphtheria commonly receive a serum with antibodies against the pathogen. What type of immunity would this be? A. Active, natural immunity B. Passive, artificial immunity C. Passive, natural immunity D. Active, artificial immunity

(T/F) Antibodies mostly act against extracellular targets in body fluids and are therefore considered part of the humoral branch of adaptive immunity

What type of cell is the precursor to the helper T cell? A. CD8 cell B. CD4 cell C. Regulatory T cell D. Memory T cell

Where does most exogenous antigen presentation take place? A. In blood plasma B. In the bone marrow C. In lymphoid tissue and organs D. In the thymus

Which of the following activate CD8 cells? A. Antigens on class II MHC proteins B. Peptides containing 14-17 amino acids C. Antigen fragments on class I MHC proteins D. Exogenous antigens

What type of T cell can directly attack and kill other cells, such as virus-infected cells? A. Helper T (Th) cells B. Cytotoxic T (Tc) cells C. APC D. Regulatory T (Treg) cells

Which of these mechanisms do cytotoxic T (Tc) cells use to destroy a target that is, deliver a lethal hit? A. Perforation of the membrane B. Opsonization C. Agglutination of target cells D. The seeking of cells lacking class I MHC proteins

T cells achieve self-tolerance in the A. Tonsils B. Thymus C. Bone marrow D. Lymph nodes

Which of the following are not appropriately matched? A. Helper T cells: destroy infected cells B. Cytotoxic T cells : destroy virally infected cells C. Macrophages: antigen-presenting cells D. B cells: produce free antibodies

Activated CD8 cells become A. Helper T cells B. Cytotoxic T cells C. B cells D. NK cells

An advantage to adaptive immunity is A. Its need for several cells to be activated over several days on first exposure B. The ability of its individual cells to respond to many different pathogens C. Its memory cells that provide quicker, larger and more efficient immune response upon second exposure to an antigen D. The use of antibodies that cause cell lysis and kill invading cells

Which of the following is not a type of T cell? A. Cytotoxic B. Helper C. Regulatory D. Antigenic

Regulatory T cells A. Decrease their activity as antigenic stimulus decreases B. Release cytokines that increase the activity of cytotoxic T cells and activated B cells C. Aid B cells in antibody production D. May function in preventing autoimmune reactions

Which of the following statements is incorrect or false? A. Class I MHC molecules are built into the plasma membranes of almost all body cells B. Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens C. MHC proteins are the cell's identify markers D. Haptens lack immunogenicity unless attached to protein carriers

Cytotoxic T cells A. Function mainly to stimulate the proliferation of other T cell populations B. Self-destruct once the antigen has been neutralized C. Require the double recognition signal of class I MHC plus class II MHC on the target cell in order to function D. Can directly attack and kill other cells of the body

Helper T cells A. Often function to decrease the immune response B. Release B7 proteins C. Bind tightly to target cells and release a lymphotoxin called perforin D. Function in the adaptive immune system activation

Which of the following cells has the largest role and most widespread effect on immunity? A. Helper T cell B. APC C. Cytotoxic T cell D. B cell

A class I MHC protein presents an antigen. What type of cell is likely presenting and to what type of cell would it be presented? A. An antigen-presenting cell would be presented to a T helper cell. B. Any nucleated cell would be presented to a CD4 cell C. An antigen-presenting cell would be presented to a CD4 cell D. Any nucleated cell would be presented to a CD8 cell

What types of antigen do T cells not recognize? A. Processed fragments of protein antigens displayed on surfaces of body cells B. Self-antigens C. Bacterial antigens D. Cancer antigens

(T/F) B cells must accomplish double recognition. They must simultaneously recognize self and nonself to be activated.

Which of the following examples below describes an autoimmune disease? A. Infection and death of T-helper cells by a virus, resulting in a loss o adaptive immunity B. Antibody binding to acetylcholine receptors of the motor end plate resulting in muscle weakness C. Release of bacterial endotoxins that block acetylcholine release result in muscle paralysis D. Uncontrolled cell division resulting in cell surface abnormalities recognized by NK cells

Allergens differ from antigens because A. Allergens do not involve leukocytes, they simply stimulate the inflammatory response B. Allergens produce an abnormally large immune response to what is an otherwise harmless particle C. Allergens are primarily plant derived while antigens are bacterial or viral in nature D. Allergens are only active seasonally and are generally harmless to the body