Ch 8 Adaptive Immunity, Ch 9 Alterations in Immunity and Inflammation, Chapter 10: Infection, Ch 11 Stress and Disease

Histamine release leads to which of the following? (Select all that apply.) a. Bronchial smooth muscle contraction b. Bronchoconstriction c. Decreased vascular permeability d. Vasoconstriction e. Edema

A,B,E Histamine contracts bronchial smooth muscle, which causes bronchoconstriction. Vascular permeability, edema, and vasodilation also increase.

Which are stages in the development of the general adaptation syndrome? (Select all that apply.) a. Alarm b. Exposure c. Resistance d. Exhaustion

A,C,D The three successive stages in the development of the general adaptation syndrome are alarm, resistance, and exhaustion.

30. Which cell has a role in developing cell-mediated immunity? a. Th1 b. CD4 c. CD8 d. Th2

ANS: A Only Th1 cells help develop cellular immunity.

14. Graves disease (hyperthyroidism) is an example of which type II hypersensitivity reaction? a. Modulation b. Antibody-dependent cell-mediated cytotoxicity c. Neutrophil-mediated damage d. Complement-mediated lysis

ANS: A The antibody reacts with the receptors on the target cell surface and modulates the function of the receptor by preventing interactions with their normal ligands, replacing the ligand and inappropriately stimulating the receptor or destroying the receptor. For example, in the hyperthyroidism (excessive thyroid activity) of Graves disease, autoantibody binds to and activates receptors for thyroid-stimulating hormone (TSH) (a pituitary hormone that controls the production of the hormone thyroxine by the thyroid). Graves disease is not a result of cell-mediated cytotoxicity, neutrophil-mediated damage, or complement-mediated lysis.

What is the first stage in the infectious process? a. Invasion b. Colonization c. Spread d. Multiplication

ANS: B From the perspective of the microorganisms that cause disease, the infectious process undergoes four separate stages of progression: (1) colonization, (2) invasion, (3) multiplication, and (4) spread.

12. Which antibody initially indicates a typical primary immune response? a. IgG b. IgM c. IgA d. IgE

ANS: B Typically, IgM is produced first (primary immune response), followed by IgG against the same antigen. IgA and IgE are not involved in the typical primary immune response.

10. Where are antibodies produced? a. Helper T lymphocytes b. Thymus gland c. Plasma cells d. Bone marrow

ANS: C An antibody or immunoglobulin is a serum glycoprotein produced only by plasma cells in response to a challenge by an immunogen. Antibodies are not produced by the thymus gland, bone marrow, or by helper T lymphocytes.

28. How many months does it take for the newborn to be sufficiently protected by antibodies produced by its own B cells? a. 1 to 2 b. 4 to 5 c. 6 to 8 d. 10 to 12

ANS: C By 6 to 8 months, the newborn should be efficiently protected by antibodies produced by its own B cells.

1. Exhaustion occurs if stress continues when which stage of the general adaptation syndrome is not successful? a. Flight or fight b. Alarm c. Adaptation d. Arousal

ANS: C Exhaustion occurs if stress continues and adaptation is not successful, ultimately causing impairment of the immune response, heart failure, and kidney failure, leading to death. The other stages occur before the adaptation stage.

Which statement about vaccines is true? a. Most bacterial vaccines contain attenuated organisms. b. Most viral vaccines are made by using dead organisms. c. Vaccines require booster injections to maintain life-long protection. d. Vaccines provide effective protection against most infections.

ANS: C In general, vaccine-induced protection does not persist as long as infection-induced immunity, thus booster injections may be necessary to maintain protection throughout life. The other options are not true of vaccines.

5. During an IgE-mediated hypersensitivity reaction, which leukocyte is activated? a. Neutrophils b. Monocytes c. Eosinophils d. T lymphocytes

ANS: C Of the options provided, only eosinophils are activated during IgE-mediated hypersensitivity reactions.

What is a significant cause of morbidity and mortality worldwide? a. Starvation b. Traumatic injury c. Cardiovascular disease d. Infectious disease

ANS: D Despite the wide-scale implementation of progressive public health and immunization policies, infectious disease remains a significant cause of morbidity and mortality. The other options are not significant causes.

34. Cytokines are vital to a cell's ability to do which function? a. Excrete b. Reproduce c. Metabolize d. Communicate

ANS: D During their interactions, cells must communicate with each other through soluble cytokines. The other options are not so rigidly related to cytokines.

25. Which class of immunoglobulins forms isohemagglutinins? a. IgA b. IgE c. IgG d. IgM

ANS: D Naturally occurring antibodies, called isohemagglutinins, are immunoglobulins of only the IgM class.

23. Which blood cell carries the carbohydrate antigens for blood type? a. Platelets b. Neutrophils c. Lymphocytes d. Erythrocytes

ANS: D The reaction that causes a blood transfusion recipient's red blood cells to clump together is related to the ABO antigens located on the surface of only erythrocytes.

Which antigen is too small to initiate an immune response? a. Carrier b. Allergen c. Hapten d. Self-antigen

C A hapten is a molecule that is foreign but too small to induce an immune response alone. However, when it binds to a larger carrier molecule, it is able to induce an immune response. An allergen is an antigen that can induce an allergic response. A self-antigen is not foreign but has the three other criteria to be an immunogen.

What antibody binds to a mast cell? a. Cytotropic b. Allergen c. Antigen d. Fc

A A cytotropic antibody (also called a reagin) is the antibody that binds to the mast cell. An allergen is an environmental antigen that induces an allergic response. An antigen stimulates the immune response and antibody to bind to the mast cell. The Fc is the portion of the mast cell where IgE binds.

Which statement is true regarding hypersensitivity reactions? a. They require sensitization against a particular antigen. b. They occur after the primary immune response. c. Reactions are always delayed. d. The most delayed reaction is anaphylaxis.

A A hypersensitivity reaction requires sensitivity to an antigen and occurs after an adequate secondary immune response. These reactions may then be immediate or delayed. The most immediate reaction is anaphylaxis.

Which definition is true? a. Allergy means the deleterious effects of hypersensitivity. b. Immunity means an altered immunologic response. c. Hypersensitivity means the protective response to an antigen. d. Autoimmunity means the normal response to foreign antigens.

A Allergy means the deleterious effects of hypersensitivity to environmental antigens. Immunity is an organism's ability to resist disease. Hypersensitivity is an altered immunologic response to an antigen that results in disease or damage to the host. Autoimmunity is a disturbance in the immunologic tolerance of self-antigens.

Which statement regarding corticotropin-releasing hormone (CRH) and its influence on the immune system is true? a. CRH is also released from peripheral inflammatory sites. b. CRH causes vasoconstriction. c. CRH causes decreased vascular permeability. d. Red blood cells are the peripheral targets.

A CRH is released from the hypothalamus and from peripheral inflammatory sites. Because this hormone is proinflammatory, it causes vasodilation and increased vascular permeability. The primary target of peripheral CRH is the mast cell.

Which statement is true of serum sickness? a. Immune complexes are formed and deposited in target issues. b. Immune complexes are formed and deposited in the blood vessels. c. It is considered a Type II hypersensivity response. d. Cytotoxic T lymphocytes are responsible for the condition.

A Serum sickness reactions are caused by the formation of immune complexes in the blood and their deposition in target tissues. An Arthus reaction deposits complexes into the walls of blood vessels. Serum sickness is a Type III hypersensitivity reaction. Type IV mechanisms occur through either cytotoxic T lymphocytes or lymphokine-producing T-helper (Th) 1 cells.

A stress response results in the stimulation of which sympathetic nervous system receptors? a. α-Adrenergic receptors b. Anterior pituitary receptors c. Adrenocorticotropic hormone (ACTH) d. Growth hormone (GH)

A The alpha receptors of the sympathetic nervous system are stimulated during the stress response and promote the release of catecholamines. The anterior pituitary receptors when stimulated result in ACTH and growth hormone production.

Which term describes the type of immunity that occurs when preformed antibodies are transferred from a donor to a recipient? a. Passive b. Active c. Memory d. Cellular

A The two types of adaptive immunity are active and passive. Passive immunity occurs when preformed antibodies are transferred from a donor to a recipient. An example of passive immunity is the passage of maternal antibodies across the placenta to the fetus. Active immunity is produced by an individual after either a natural exposure or an immunization. Memory cells are formed through cellular and humoral immunity; they remember the antigen.

Which criteria influence the degree of immunogenicity? (Select all that apply.) a. Foreignness to the host b. Appropriate size c. Appropriate quantity d Chemical simplicity e. Chemical complexity

A, B, C, E The four criteria that influence the degree of immunogenicity are foreignness to the host, appropriate size, appropriate quantity, and chemical complexity.

Where does the perception of stress initiate? (Select all that apply.) a. Peripheral nervous system b. Exocrine system c. Parasympathetic nervous system d. Central nervous system

A,D The perception of stress is initiated in the central nervous and peripheral nervous systems.

18. A reduction in an individual's number of natural killer (NK) cells appears to correlate with an increased risk for the development of what? a. Depression b. Type 1 diabetes c. Obsessive compulsive disorder (OCD) d. Gastroesophageal reflux disorder (GERD)

ANS: A A meta-analysis of studies shows a relationship between depression and the reduction in lymphocyte proliferation and natural killer cell activity. Currently, no research supports correlations between the number of NK cells and type 1 diabetes, OCD, or GERD.

21. Which statement is believed to be true concerning Th2 cells? a. Th2 cells are induced by antigens derived from allergens. b. They are induced by antigens derived from cancer cells. c. Th2 cells produce IL-2, TNF-ß, and IFN-γ. d. They assist in the development of cell-mediated immunity.

ANS: A Antigens derived from multicellular parasites and allergens are hypothesized to be involved in the production of more Th2 cells. Th1 cells are induced by antigens derived from cancer cells. Th2 cells produce IL-4, IL-5, IL-6, and IL-13.

24. The healthcare professional working with older adults teaches general infection-prevention measures as a priority for this age group due to which change in lymphocyte function? a. Increased production of antibodies against self-antigens b. Decreased number of circulating T cells c. Decreased production of autoantibodies d. Increased production of helper T cells

ANS: A B-cell function is altered with age as shown by decreases in specific antibody production in response to antigenic challenge, with concomitant increases in circulating immune complexes and in circulating autoantibodies (antibodies against self-antigens). Aging does not play a role in either decreasing T cells circulation or increasing helper T cells production.

35. A person with type O blood is considered to be the universal blood donor because type O blood contains which of these? a. No antigens b. No antibodies c. Both A and B antigens d. Both A and B antibodies

ANS: A Because individuals with type O blood lack both types of antigens, they are considered universal donors, meaning that anyone can accept their red blood cells. Type O individuals, who have neither A or B antigen but have both anti-A and anti-B antibodies, cannot accept blood from any of the other three types.

10. What effect of increased secretions of epinephrine, glucagon, and growth hormone would the healthcare professional assess for? a. Hyperglycemia b. Hypertension c. Bronchodilation d. Pupil dilation

ANS: A Cortisol enhances the elevation of blood glucose promoted by other hormones, such as epinephrine, glucagon, and growth hormone. Increases in glucagon and growth hormone do not lead to increases in blood pressure, bronchodilation, or pupil dilation although epinephrine does.

10. When mismatched blood is administered causing an ABO incompatibility, how are the erythrocytes destroyed? a. Complement-mediated cell lysis b. Phagocytosis by macrophages c. Phagocytosis in the spleen d. Natural killer cells

ANS: A Erythrocytes are destroyed by complement-mediated lysis in individuals with autoimmune hemolytic anemia or as a result of an alloimmune reaction to ABO-mismatched transfused blood cells. Erythrocytes are not destroyed by phagocytosis or natural killer cells.

34. Which statement is true regarding immunodeficiency? a. Immunodeficiency is generally not present in other family members. b. Immunodeficiency is never acquired; rather, it is congenital. c. Immunodeficiency is almost immediately symptomatic. d. Immunodeficiency is a result of a postnatal mutation.

ANS: A Generally, the genetic mutations that cause immunodeficiency are sporadic and not inherited; a family history exists in only approximately 25% of individuals. The sporadic mutations occur before birth, but the onset of symptoms may be early or later, depending on the particular syndrome. The immunodeficiency can be either congenital or acquired.

15. The generation of clonal diversity occurs primarily during which phase of life? a. Fetal b. Neonatal c. Infancy d. Puberty

ANS: A Generation of clonal diversity primarily occurs in the fetus and probably continues to a low degree throughout most of adult life

What area in the body may act as a reservoir in which HIV can be relatively protected from antiviral drugs? a. Central nervous system b. Bone marrow c. Thymus gland d. Lungs

ANS: A HIV may persist in regions where the antiviral drugs are not as effective, such as the central nervous system (CNS). The other options are not as protected from antiviral drugs.

7. A patient is having an IgE-mediated hypersensitivity reaction. What action by the healthcare professional is best? a. Give the patient an antihistamine. b. Prepare to give the patient a blood transfusion. c. Ask the patient is he/she is having pain at the site. d. Apply warm, moist heat to the affected area.

ANS: A Histamine is the most potent mediator in an IgE-mediated hypersensitivity reaction (Type 1). Histamine bound to H2 results in the degranulation of mast cells with the release of histamine. Blocking histamine receptors with antihistamines can control some type I responses. The healthcare professional would not need to give the patient blood; warm; moist heat; or ask about pain.

36. Immunoglobulin E (IgE) is associated with which type of hypersensitivity reaction? a. I b. II c. III d. IV

ANS: A Hypersensitivity reactions have been divided into four distinct types: type I (IgE-mediated) hypersensitivity reactions, type II (tissue-specific) hypersensitivity reactions, type III (immune complex-mediated) hypersensitivity reactions, and type IV (cell-mediated) hypersensitivity reactions.

11. Which immunoglobulin is present in blood, saliva, breast milk, and respiratory secretions? a. IgA b. IgE c. IgG d. IgM

ANS: A IgA can be divided into two subclasses, IgA1 and IgA2. IgA1 molecules are predominantly found in the blood, whereas IgA2 is the predominant class of antibody found in normal body secretions.

The ability of the pathogen to invade and multiply in the host is referred to as: a. Infectivity b. Toxigenicity c. Pathogenicity d. Virulence

ANS: A Infectivity is the ability of the pathogen to invade and multiply in the host. The other options do not accurately denote the pathogen's ability to invade and multiply in the host.

Phagocytosis involves neutrophils actively attacking, engulfing, and destroying which microorganisms? a. Bacteria b. Fungi c. Viruses d. Yeasts

ANS: A Invasion is the direct confrontation with an individual's primary defense mechanisms against only bacteria, which include the complement system, antibodies, and phagocytes, such as neutrophils and macrophages.

Considering the hypothalamus, a fever is produced by: a. Endogenous pyrogens acting directly on the hypothalamus. b. Exogenous pyrogens acting directly on the hypothalamus. c. Immune complexes acting indirectly on the hypothalamus. d. Cytokines acting indirectly on the hypothalamus.

ANS: A Little evidence suggests that exogenous pyrogens directly cause fever. Such pyrogens indirectly affect the hypothalamus through endogenous pyrogens released by cells of the host. Neither immune complexes nor cytokines are involved in the process.

9. The functions of the major histocompatibility complex (MHC) and CD1 molecules are alike because both do what? a. Are antigen-presenting molecules b. Bind antigens to antibodies c. Secrete interleukins during the immune process d. Are capable of activating cytotoxic T lymphocytes

ANS: A MHC and CD1 molecules are both antigen presenting molecules (APCs). Antigen binding fragments bind antigens to antibodies. Interleukins have many sources, but they are not secreted by MHCs and CD1 molecules. Activating cytotoxic T lymphocytes requires the presence of antigen presentation and effector Th cells.

5. What type of immunity is produced when an immunoglobulin crosses the placenta? a. Passive-acquired immunity b. Active-acquired immunity c. Passive-innate immunity d. Active-innate immunity

ANS: A Passive-acquired immunity (passive immunity) does not involve the host's immune response at all. Rather, passive immunity occurs when preformed antibodies or T lymphocytes are transferred from a donor to the recipient. This transfer can occur naturally, as in the passage of maternal antibodies across the placenta to the fetus, or artificially, as in a clinic using immunotherapy for a specific disease. The remaining options do not produce immunity via immunoglobulin transfer across the placenta.

18. A healthcare professional is teaching a patient about Raynaud phenomenon and instructs the patient to avoid cold. What is the best explanation of how cold impacts the manifestations of this disease? a. Immune complexes that are deposited in capillary beds, blocking circulation b. Mast cells that are bound to specific endothelial receptors, causing them to degranulate and creating a localized inflammatory reaction that occludes capillary circulation c. Cytotoxic T cells that attack and destroy the capillaries so that they are unable to perfuse local tissues d. Antibodies that detect the capillaries as foreign protein and destroy them using lysosomal enzymes and toxic oxygen species

ANS: A Raynaud phenomenon is a condition (type III hypersensitivity reaction) caused by the temperature-dependent deposition of immune complexes in the capillary beds of the peripheral circulation. The healthcare professional should teach the patient to avoid cold or to wear gloves to mitigate the cold. None of the other options are involved in causing this condition.

3. What is the term for the process during which lymphoid stem cells migrate and change into either immunocompetent T cells or immunocompetent B cells? a. Clonal diversity b. Clonal differentiation c. Clonal selection d. Clonal competence

ANS: A The process is called the generation of clonal diversity and occurs in specialized (primary) lymphoid organs—the thymus gland for T cells and the bone marrow for B cells. Clonal differentiation, selection, and competence do not describe this process.

22. A patient asks the healthcare professional why tissue damage occurs in acute rejection after organ transplantation. What response by the professional is best? a. Th1 cells release cytokines that activate infiltrating macrophages, and cytotoxic T cells directly attack the endothelial cells of the transplanted tissue. b. Circulating immune complexes are deposited in the endothelial cells of transplanted tissue, where the complement cascade lyses tissue. c. Receptors on natural killer cells recognize antigens on the cell surface of transplanted tissue, which releases lysosomal enzymes that destroy tissue. d. Antibodies coat the surface of transplanted tissue to which mast cells bind and liberate preformed chemical mediators that destroy tissue.

ANS: A The recipient's lymphocytes interacting with the donor's dendritic cells within the transplanted tissue usually initiate sensitization, resulting in the induction of recipient Th1 and Tc cells against the donor's antigens. The Th1 cells release cytokines that activate infiltrating macrophages, and the Tc cells directly attack the endothelial cells in the transplanted tissue. The other options do not accurately describe how acute rejection after organ transplantation results in tissue damage.

4. Which hormone prompts increased anxiety, vigilance, and arousal during a stress response? a. Norepinephrine b. Epinephrine c. Cortisol d. Adrenocorticotropic hormone (ACTH)

ANS: A The release of norepinephrine promotes arousal, increased vigilance, increased anxiety, and other protective emotional responses. Epinephrine's effects are primarily on the cardiovascular system. Cortisol's chief effects involve metabolic processes. By inhibiting the use of metabolic substances while promoting their formation, cortisol mobilizes glucose, amino acids, lipids, and fatty acids and delivers them to the bloodstream. ACTH binds with specific receptors on the adrenal glands which causes the release of the glucocorticoids.

27. A child in the clinic has an absence of a parathyroid gland, structural heart defects, and a shortened structure of the upper lip. What immune dysfunction does the healthcare professional suspect? a. Partial-to-complete absence of T-cell immunity b. X-linked recessive microcephaly c. An autoimmune disease like systemic lupus erythematosus d. Adenosine deaminase deficiency

ANS: A This child has the clinical features of DiGeorge disease, which is caused by a partial-to-complete absence of T-cell immunity.

32. Which statement is true regarding maternal antibodies provided to the neonate? a. The antibodies enter into the fetal circulation by means of active transport. b. The antibodies are transferred to the fetus via the lymphatic system. c. The antibodies are directly related to the mother's nutritional intake. d. The antibodies reach protective levels after approximately 6 months of age.

ANS: A To protect the child against infectious agents both in utero and during the first few postnatal months, a system of active transport facilitates the passage of maternal antibodies into the fetal circulation. The antibodies are transmitted via the placenta and are related to the mother's immune system. The infant's own IgG-related antibodies reach protective levels by 6 months of age. The antibodies are not transferred via the lymphatic system, are not directly related to maternal nutrition, or reach protective levels after 6 months of age.

3. The common hay fever allergy is expressed through a reaction that is mediated by which class of immunoglobulins? a. IgE b. IgG c. IgM d. T cells

ANS: A Type I reactions are mediated by antigen-specific IgE and the products of tissue mast cells. The most common allergies (e.g., pollen allergies) are type I reactions. In addition, most type I reactions occur against environmental antigens and are therefore allergic. Hay fever allergy is not mediated by IgG, IgM, or T cells.

28. Which statement is true concerning IgM? a. IgM is the first antibody produced during the initial response to an antigen. b. IgM mediates many common allergic responses. c. IgM is the most abundant class of immunoglobulins. d. IgM is capable of crossing the human placenta.

ANS: A Typically, IgM is produced first (primary immune response), followed by IgG against the same antigen. IgE mediates allergic responses and is active in the defense against parasitic infections. IgG is the most abundant immunoglobulin class and can cross the human placenta to enter into fetal circulation.

40. Which disorders are considered autoimmune? (Select all that apply.) a. Crohn disease b. Addison disease c. Rheumatoid arthritis d. Systemic lupus erythematosus e. Type 2 diabetes

ANS: A, B, C, D Crohn disease, Addison disease, rheumatoid arthritis, and systemic lupus erythematosus are all diseases that result from autoimmune pathologic conditions. Insulin-dependent diabetes is also an autoimmune disorder, but type 2 diabetes is not.

CD4 is a characteristic surface marker and a result of which of these? (Select all that apply.) a. Activity in the primary lymphoid organs b. Process of cellular differentiation c. Alterations to T cells d. Changes to B cells e. Clonal selection

ANS: A, B, C, D Differentiation of B cells and T cells in the primary lymphoid organs results in the expression of several characteristic surface markers, such as CD4 on helper T cells, CD8 on cytotoxic T cells, and CD21 and CD40 on B cells. Clonal selection is the process during which antigens select those lymphocytes with complementary T-cell receptors (TCRs) or BCRs.

21. Which statements are true regarding lymphocytes? (Select all that apply.) a. Lymphocytes are involved in the production of the human growth hormone. b. Elevated catecholamine levels influence lymphocytes. c. Lymphocytes are synthesized in the anterior pituitary gland. d. Lymphocytes have receptors for the hormone prolactin. e. Lymphocytes produce endorphins in large amounts.

ANS: A, B, D GH is synthesized from the anterior pituitary gland and is produced by lymphocytes and mononuclear phagocytic cells. Several classes of lymphocytes have receptors for prolactin, suggesting a direct effect of prolactin on immune function. Although the effects of acute elevation of catecholamines on the alteration of lymphocyte function are real, they are short-lived, lasting only approximately 2 hours. Lymphocytes are not synthesized in the anterior pituitary gland or produce endorphins in large amounts.

39. Exposure to which of these could result in a type IV hypersensitivity reaction? (Select all that apply.) a. Poison ivy b. Neomycin c. Dairy products d. Nickel e. Detergents

ANS: A, B, D, E Allergens that primarily elicit type IV allergic hypersensitivities include plant resins (e.g., poison ivy, poison oak); metals (e.g., nickel, chromium); acetylates and chemicals in rubber, cosmetics, detergents; and topical antibiotics (e.g., neomycin). Food products typically result in type I hypersensitivity reactions.

41. Which statements best define acute rejection? (Select all that apply.) a. Acute rejection is a cell-mediated immune response. b. Acute rejection is usually a type III rejection. c. Immunosuppressive drugs delay or lessen the intensity of an acute rejection. d. Acute rejection is associated with the body's response to an organ transplant. e. Acute rejection is a response against unmatched human leukocyte antigens (HLAs).

ANS: A, C, D, E Acute rejection is primarily a cell-mediated immune response that occurs within days to months after transplantation. This type of rejection occurs when the recipient develops an immune response against unmatched HLAs after transplantation. A biopsy of the rejected organ usually shows an infiltration of lymphocytes and macrophages characteristic of a type IV reaction. Immunosuppressive drugs may delay or lessen the intensity of an acute rejection.

What are the necessary components of an adaptive immune response? (Select all that apply.) a. Antigen b. Gamma IgG c. Lymphocyte surface receptors d. Crystalline fragment e. Antibody

ANS: A, C, E Antigens are the molecules that can react with components of the adaptive immune system, including antibodies and lymphocyte surface receptors. Gamma IgG and crystalline fragment are not necessary components of an adaptive immune response.

22. Which cytokines initiate the production of corticotropin-releasing hormone (CRH)? (Select all that apply.) a. IL-1 b. IL-6 c. TNF-ß d. IFN e. IL-12

ANS: A,B Although a number of stress factors initiate the production of CRH, of the options available, only high levels of IL-1 and IL-6 initiate such a response.

19. The effect epinephrine has on the immune system during the stress response is to increase which cells? (Select all that apply.) a. NK cells b. Immunoglobulins c. Cytokines d. T cells e. Th cells

ANS: A,D The injection of epinephrine into healthy human beings is associated with a transient increase of the number of lymphocytes (e.g., T cells, natural killer (NK) cells) in the peripheral blood. This association is not true of the other options.

4. What are blood transfusion reactions an example of? a. Autoimmunity b. Alloimmunity c. Homoimmunity d. Hypersensitivity

ANS: B Alloimmunity (also termed isoimmunity) occurs when the immune system of one individual produces an immunologic reaction against tissues of another individual. Autoimmunity is a disturbance in the immunologic tolerance of self-antigens. Homoimmunity refers to the resistance of a lysogenic bacterium that is carrying a phage to an infection by the same type of phage. Hypersensitivity is an altered immunologic response to an antigen that results in disease or damage to the host.

20. An Rh-negative woman gave birth to an Rh-positive baby. When discussing Rho[D] immunoglobulin with her, what information should the healthcare professional provide? a. It provides protection against infection from poor immunity in the baby. b. It prevents alloimmunity and hemolytic anemia of the newborn. c. It provides necessary antibodies in case the mother doesn't breastfeed. d. It causes the intestinal tract of the newborn to produce antibodies.

ANS: B Alloimmunity occurs when an individual's immune system reacts against antigens on the tissues of other members of the same species. This can occur when a woman is Rh-negative and gives birth to an Rh-positive baby, leading to hemolytic anemia of the newborn. Rho[D] immunoglobulin does not provide protection against infection, provide antibodies to a bottle-fed baby, or cause the intestine to produce antibodies.

4. Which type of immunity is produced by an individual after either natural exposure to the antigen or after immunization against the antigen? a. Passive-acquired immunity b. Active-acquired immunity c. Passive-innate immunity d. Active-innate immunity

ANS: B An individual produces active-acquired immunity (active immunity) after natural exposure to an antigen or after immunization, whereas passive-acquired immunity (passive immunity) does not involve the host's immune response at all. The innate immune system, also known as nonspecific immune system and the first line of defense, is composed of the cells and mechanisms that defend the host from infection by other organisms in a nonspecific manner, which means that the cells of the innate system recognize and respond to pathogens in a generic way.

14. Which statement is true concerning the differences between stress-induced hormonal alterations of men and women? a. After injury, women produce more proinflammatory cytokines than men, a profile that is associated with poor outcomes. b. Androgens appear to induce a greater degree of immune cell apoptosis after injury, creating greater immunosuppression in injured men than in injured women. c. Psychologic stress associated with some types of competition decreases both testosterone and cortisol, especially in athletes older than 45 years of age. d. After stressful stimuli, estrogen is increased in women, but testosterone is decreased in men.

ANS: B Androgens appear to induce a greater degree of immune cell apoptosis after injury, a mechanism that may elicit a greater immunosuppression in injured men vs. injured women. Men produce more proinflammatory cytokines. Competitive stress increases testosterone and cortisol. Estrogen is not increased in women after stressful stimuli.

HIV antibodies appear within how many weeks after infection through blood products? a. 1 to 2 b. 4 to 7 c. 10 to 12 d. 20 to 24

ANS: B Antibody appears rather rapidly after infection through blood products, usually within 4 to 7 weeks.

After sexual transmission of HIV, a person can be infected yet seronegative for how many months? a. 1 to 2 c. 18 to 20 b. 6 to 14 d. 24 to 36

ANS: B Antibody appears rather rapidly after infection through blood products, usually within 4 to 7 weeks. After sexual transmission, however, the individual can be infected yet seronegative for 6 to 14 months or, in at least one case, for years.

15. Type III hypersensitivity reactions are a result of which of these? a. Antibodies coating mast cells by binding to receptors that signal its degranulation, followed by the discharge of preformed mediators b. Antibodies binding to soluble antigens that were released into body fluids and the immune complexes being deposited in the tissues c. Tc cells or lymphokine-producing Th1 cells directly attacking and destroying cellular targets d. Antibodies binding to the antigen on the cell surface

ANS: B Antigen-antibody (immune) complexes that are formed in the circulation and then deposited later in vessel walls or extravascular tissues cause most type III hypersensitivity diseases. Type III hypersensitivity reactions are not the result of antibodies coating mast cells to signal their degranulation, immune cells directly attacking and destroying targets, or antibodies binding to the antigen on the cell surface.

20. Which statement is believed to be true concerning Th1 cells? a. Th1 cells are induced by antigens derived from allergens. b. They are induced by antigens derived from cancer cells. c. Th1 cells produce IL-4, IL-5, IL-6, and IL-13. d. They assist in the development of humoral immunity.

ANS: B Antigens derived from viral or bacterial pathogens and those derived from cancer cells are hypothesized to induce a greater number of Th1 cells relative to Th2 cells. The other statements are not true regarding Th1 cells.

27. Evaluation of umbilical cord blood can confirm that which immunoglobulin level is near adult levels? a. IgA b. IgG c. IgM d. IgE

ANS: B At birth, the total IgG level in the umbilical cord is the only immunoglobulin that is near adult levels. This is due to a system of active transport that facilitates the passage of maternal antibodies into the fetal circulation. The other antibodies are not present at this level in the newborn.

33. Which statement is true concerning an atopic individual? a. They tend to produce less IgE. b. They tend to produce more Fc receptors. c. They tend to attract very few mast cells. d. They tend to produce very high levels of IgM.

ANS: B Atopic individuals tend to produce higher quantities of IgE and have more Fc receptors for IgE on their mast cells. Atopic individuals tend to produce more, not less, IgE. Manifestations these individuals display are influenced greatly by the release of histamine from mast cells, which are found in large numbers in the affected tissue. An IgM response is a mainstay of type II responses.

6. A student asks the healthcare professional how immunity is decreased by stress. The professional responds that during a stress response, the helper T (Th) 1 response is suppressed by which hormone? a. ACTH b. Cortisol c. Prolactin d. Growth hormone

ANS: B Cortisol acts to suppress the activity of Th1 cells, which leads to a decrease in innate immunity and the proinflammatory response. Cortisol also stimulates the activity of Th2 cells, which increases adaptive immunity and the antiinflammatory response. ACTH binds with specific receptors on the adrenal glands which causes the release of the glucocorticoids. Prolactin is secreted in response to a variety of stressful stimuli and acts as a second messenger for IL-2 and has a positive influence on B-cell activation and differentiation. Growth hormone affects protein, lipid, and carbohydrate metabolism; counters effects of insulin; and is involved in tissue repair.

2. What is a hypersensitivity reaction that produces an allergic response called? a. Hemolytic shock b. Anaphylaxis c. Necrotizing vasculitis d. Systemic erythematosus

ANS: B Examples of systemic anaphylaxis are allergic reactions to beestings, peanuts, and fish. Hemolytic shock would be a state in which erythrocytes are destroyed by complement-mediated lysis to the point of causing a state of shock. Necrotizing vasculitis is inflammation of blood vessel walls that limits perfusion. Systemic lupus erythematosus (SLE) is a chronic, multisystem, inflammatory disease and is one of the most common, complex, and serious of the autoimmune disorders.

7. Which characteristic is the most important determinant of immunogenicity when considering the antigen? a. Size b. Foreignness c. Complexity d. Quantity

ANS: B Foremost among the criteria for immunogenicity is the antigen's foreignness. A self-antigen that fulfills all of these criteria except foreignness does not normally elicit an immune response. Thus most individuals are tolerant of their own antigens. The immune system has an exquisite ability to distinguish self (self-antigens) from nonself (foreign antigens). Size, complexity, and quantity are considered when determining immunogenicity but not to the extent that foreignness is.

37. A pregnant woman has Graves disease. What test/s does the healthcare professional advise the woman about? a. Frequent tests of the newborn's muscular strength and movement. b. Blood test for hyperthyroidism c. Monthly OB checkups for fetal anomalies or pregnancy loss d. Serum complete blood count including platelet count

ANS: B Graves disease is an autoimmune disease in which maternal antibody against the receptor for TSH causes neonatal hyperthyroidism. The healthcare professional should advise the woman that her newborn will need to be tested for hyperthyroidism.

Which statement is a characteristic of HIV? a. HIV only infects T-helper (Th) cells. b. HIV is a retrovirus. c. HIV carries genetic information in its DNA. d. HIV has five identified strains.

ANS: B HIV is a member of the retrovirus family, which carries genetic information in the form of two copies of RNA (see Figure 10-12). The other statements are not true of HIV.

8. A severely stressed patient has cold, clammy skin. The healthcare professional quizzes the student about this effect. The student correctly answers that this effect is directly from which action? a. Epinephrine dilating blood vessels leading to the vital organs b. Norepinephrine constricting blood vessels in the skin c. Dilating the airways to increased oxygenation of the tissues d. Dysfunctional temperature regulation from cortisol secretion

ANS: B In a stress response, the actions of norepinephrine and epinephrine are complementary. While epinephrine dilates blood vessels to the vital organs (among other things), norepinephrine constricts blood vessels in the viscera and skin, providing more blood supply for those vital organs. The clinical result is cold, clammy skin. Epinephrine can also dilate airways, but this does not produce the skin changes as described. Temperature dysregulation is not the cause of the cold, clammy skin.

Vaccines against viruses are created from: a. Killed organisms or extracts of antigens b. Live organisms weakened to produce antigens c. Purified toxins that have been chemically detoxified d. Recombinant pathogenic protein

ANS: B Most vaccines against viral infections (e.g., measles, mumps, rubella, varicella [chickenpox], rotavirus) contain live viruses that are weakened (attenuated) to continue expressing the appropriate antigens but are unable to establish more than a limited and easily controlled infection. The other options are not used in virus-focused vaccines.

19. Deficiencies in which element can produce depression of both B- and T-cell function? a. Iron b. Zinc c. Iodine d. Magnesium

ANS: B Of the options available, only deficient zinc intake can profoundly depress T- and B-cell function.

18. Which cytokine is needed for the maturation of a functional helper T cell? a. IL-1 b. IL-2 c. IL-4 d. IL-12

ANS: B Of the options provided, IL-2 production is critical for the Th cell to mature efficiently into a functional helper cell.

Which is an example of an endogenous antigen? a. Yeast b. Cancer cells c. Bacteria d. Fungus

ANS: B Of the options provided, endogenous antigens include only those uniquely produced by cancerous cells.

Which type of microorganism reproduces on the skin? a. Viruses b. Bacteria and fungi c. Protozoa and Rickettsiae d. Mycoplasma

ANS: B Only bacteria and fungi have the capacity to reproduce on the skin.

29. Considering the effects of nutritional deficiencies on the immune system, severe deficits in calories and protein lead to deficiencies in the formation of which immune cells? a. B cells b. T cells c. Natural killer cells d. Neutrophils

ANS: B Severe deficits in calorie or protein intake lead to deficiencies in T-cell function and numbers. B cells, natural killer cells, and neutrophils are not necessarily affected by nutritional deficits.

2. Which organ is stimulated during the alarm phase of the general adaptation syndrome (GAS)? a. Adrenal cortex b. Hypothalamus c. Anterior pituitary d. Limbic system

ANS: B The alarm phase of the GAS begins when a stressor triggers the actions of the hypothalamus and the sympathetic nervous system (SNS). The other organs are not stimulated by the alarm phase of GAS.

32. Raynaud phenomenon is an example of which type of hypersensitivity? a. IV b. III c. II d. I

ANS: B The characteristics of serum sickness are observed in only systemic type III autoimmune diseases such as Raynaud phenomenon.

Which statement is true concerning a fungal infection? a. Fungal infections occur only on skin, hair, and nails. b. Phagocytes and T lymphocytes control fungal infections. c. Fungal infections release endotoxins. d. Vaccines prevent fungal infections.

ANS: B The host defense against fungal infection includes the fungistatic properties of neutrophils and macrophages. T lymphocytes are crucial in limiting the extent of infection and producing cytokines to further activate macrophages. The other options are not true of fungal infections.

Which cells are primary targets for HIV? a. CD4+ Th cells only b. CD4+ Th cells, macrophages, and natural killer cells c. CD8-positive cytotoxic T (Tc) cells and plasma cells d. CD8-positive Tc cells only

ANS: B The primary cellular targets for HIV include CD4+ Th cells, macrophages, and NK cells. The other options are not the primary target cells of HIV.

25. How do antibodies protect the host from bacterial toxins? a. Lysing the cell membrane of the toxins b. Binding to the toxins to neutralize their biologic effects c. Inhibiting the synthesis of DNA proteins needed for growth d. Interfering with the DNA enzyme needed for replication

ANS: B To cause disease, most toxins must bind to surface molecules on the individual's cells. Protective antibodies can bind to the toxins, prevent their interaction with cells, and neutralize their biologic effects. Antibodies do not lyse the toxin cell membrane, inhibit the synthesis of DNA, or interfere with DNA replication.

Toxigenicity is defined as the: a. Ability of the pathogen to invade and multiply in the host b. Pathogen's ability to produce disease by the production of a soluble toxin c. Ability of an agent to produce disease d. Potency of a pathogen measured in terms of the number of microorganisms required to kill the host

ANS: B Toxigenicity is the ability of a pathogen to produce soluble toxins or endotoxins, which are factors that greatly influence the pathogen's degree of virulence. The other options do not accurately define toxigenicity.

1. Which primary characteristic is unique for the immune response? a. The immune response is similar each time it is activated. b. The immune response is specific to the antigen that initiates it. c. The response to a specific pathogen is short term. d. The response is innate, rather than acquired.

ANS: B Unlike inflammation, which is nonspecifically activated by cellular damage and pathogenic microorganisms, the immune response is primarily designed to afford long-term specific protection (i.e., immunity) against particular invading microorganisms; that is, it has a memory function. The inflammatory response is similar each time it is activate. Passive immunity is short term or temporary. The inflammatory process is innate.

23. Vaccinations are able to provide protection against certain microorganisms because of what? a. Strong response from IgM b. Level of protection provided by IgG c. Memory cells for IgE d. Rapid response from IgA

ANS: B Vaccinations provide protection by a secondary response when the individual is exposed to the microorganism to which he or she was vaccinated. At that time, IgG production is considerably increased, making it the predominant antibody class of the secondary response. IgM is more active against the primary exposure. IgE is usually seen in allergies. IgA is the predominant secretory antibody and prevents the attachment and invasion of pathogens through mucosal membranes.

36. Which statements are true concerning the humoral immune response? (Select all that apply.) a. The humoral immune response is divided into major and minor phases. b. The response has IgG and IgM produced during each of its phrases. c. It has a greater presence of IgG than IgM in one of its phases. d. The humoral immune response is produced in reaction to the presence of an antigen. e. Phases differ in their response time as a result of the effect of memory cells.

ANS: B, C, D, E The humoral immune response is divided into two phases, primary and secondary. These phases differ in the relative amounts of IgG produced—the secondary response having a significantly higher proportion of IgG relative to IgM. The two phases also differ in the speed with which each occurs after the antigen challenge—the secondary phases is significantly more rapid than the primary phase because of the presence of memory cells in the secondary phase.

20. The increased production of proinflammatory cytokines is associated with which considerations? (Select all that apply.) a. Chronic respiratory dysfunction b. Elevated anxiety levels c. Immune disorders d. Age and gender e. Dementia

ANS: B,C Increased levels of proinflammatory cytokines have been shown to have a possible link between stress and immune function. Chronic respiratory dysfunction, age, gender, and dementia are not directly linked to cytokine levels.

38. When a tuberculin skin test is positive, the hard center and erythema surrounding the induration are a result of which of these? (Select all that apply.) a. Histamine b. T lymphocytes c. Immune complexes d. Products of complement e. Macrophages

ANS: B,E The reaction site is infiltrated with T lymphocytes and macrophages, resulting in a clear hard center (induration) and a reddish surrounding area (erythema).

12. What effect do androgens have on lymphocytes? a. Suppression of B-cell responses and enhancement of T-cell responses b. Suppression of T-cell responses and enhancement of B-cell responses c. Suppression of B- and T-cell responses d. Enhancement of B- and T-cell responses

ANS: C Androgens suppress T- and B-cell responses. Androgens do not enhance either B- or T-cell responses.

11. When antibodies are formed against red blood cell antigens of the Rh system, how are the blood cells destroyed? a. Complement-mediated cell lysis b. Phagocytosis by macrophages c. Phagocytosis in the spleen d. Neutrophil granules and toxic oxygen products

ANS: C Antibodies against platelet-specific antigens or against red blood cell antigens of the Rh system coat those cells at low density, resulting in their preferential removal by phagocytosis in the spleen, rather than by complement-mediated lysis. These blood cells are not destroyed by complement-mediated cell lysis, phagocytosis by macrophages, neutrophil granules, or toxic oxygen products.

8. What characteristic do atopic individuals have that make them genetically predisposed to develop allergies? a. Greater quantities of histamine b. More histamine receptors c. Greater quantities of IgE d. A deficiency in epinephrine

ANS: C Atopic individuals tend to produce higher quantities of IgE and to have more crystalline fragment (Fc) receptors for IgE on their mast cells. Greater quantities of histamine, more histamine receptors, and a deficiency in epinephrine do not lead to a genetic predisposition to allergies.

2. In which structure does B lymphocytes mature and undergo changes that commit them to becoming B cells? a. Thymus gland b. Regional lymph nodes c. Bone marrow d. Spleen

ANS: C B lymphocytes mature and become B cells in specialized (primary) lymphoid organs—the thymus gland for T cells and the bone marrow for B cells. Neither regional lymph nodes nor the spleen are involved in changing B lymphocytes into B cells.

29. Which cell has the ability to recognize antigens presented by the MHC class I molecules? a. T cytotoxic b. CD 4 c. CD 8 d. T helper

ANS: C CD8 cells recognize antigens presented by the major histocompatibility complex (MHC) class I molecules and become mediators of cell-mediated immunity and directly kill other cells (T-cytotoxic cells). CD4 cells tend to recognize antigen presented by MHC class II molecules and develop into helpers in the later clonal selection process (T-helper cells).

17. In a type III hypersensitivity reaction, the harmful effects after the immune complexes that are deposited in tissues are a result of what? a. Cytotoxic T cells b. Natural killer cells c. Complement activation d. Degranulation of mast cells

ANS: C Complement activation, particularly through the generation of chemotactic factors for neutrophils, causes the harmful effects of immune complex deposition. The neutrophils bind to antibody and C3b contained in the complexes and attempt to ingest the immune complexes. Type III hypersensitivity reactions as described are not the result of cytotoxic T cells, natural killer cells, or degranulation of mast cells.

Cytokines are thought to cause fevers by stimulating the synthesis of which chemical mediator? a. Leukotriene b. Histamine c. Prostaglandin d. Bradykinin

ANS: C Cytokines seem to raise the thermoregulatory set point through stimulation of prostaglandin synthesis and turnover in thermoregulatory (brain) and nonthermoregulatory (peripheral) tissues. The other options do not accurately identify the appropriate chemical mediator.

6. During an IgE-mediated hypersensitivity reaction, what causes bronchospasm? a. Bronchial edema caused by the chemotactic factor of anaphylaxis b. Bronchial edema caused by binding of the cytotropic antibody c. Smooth muscle contraction caused by histamine bound to H1 receptors d. Smooth muscle contraction caused by histamine bound to H2 receptors

ANS: C During an IgE-mediated hypersensitivity reaction, smooth muscle contraction caused by histamine bound to H1 receptors results in bronchospasms. The bronchospasm is not caused by edema or by histamine binding to H2 receptors.

16. What are the signs that a patient is in the adaptive stage of the general adaptation syndrome? a. He or she begins to experience elevated heart and respiratory rates. b. He or she finds it difficult to concentrate on a solution for the stress. c. The patient perceives his or her only options are to run away or fight back. d. The patient has exceeded his or her ability to cope with the current situation.

ANS: C Fight-or-flight behaviors are characteristic of the more advanced adaptive stage, whereas the remaining options are noted in the initial alarm stage and are mediated by the sympathetic nervous system.

1. How is hypersensitivity best defined? a. A disturbance in the immunologic tolerance of self-antigens b. An immunologic reaction of one person to the tissue of another person c. An altered immunologic response to an antigen that results in disease d. An undetectable immune response in the presence of antigens

ANS: C Hypersensitivity is an altered immunologic response to an antigen that results in disease or damage to the host. Autoimmunity is a disturbance in the immunologic tolerance of self-antigens. Alloimmunity is the immunologic reaction of one person to the tissue of another person. An immune deficiency of some type would cause undetectable immune response in the presence of antigens.

15. A patient perceives living in a state of chronic stress. What will diagnostic blood work ordered by the healthcare professional likely demonstrate? a. Decreased Th lymphocytes b. Increased erythrocytes c. Decreased Tc cells d. Increased platelets

ANS: C Illustrating the influence of chronic stress appraisal on the physiologic processes, a meta-analysis of the relationships between stressors and immunity found that a higher perception of stress was associated with reduced T cytotoxic (Tc)-cell cytotoxicity, although not with levels of circulating Th or Tc lymphocytes. Research has not shown this relationship with changes in Th lymphocytes, erythrocytes, or platelets.

31. What is Graves disease a result of? a. Increased levels of circulating immunoglobulins b. The infiltration of the thyroid with T lymphocytes c. Autoantibodies binding to thyroid-stimulating hormone (TSH)-receptor sites d. Exposure to acetylates in substances such as rubber

ANS: C In the hyperthyroidism (excessive thyroid activity) of Graves disease, autoantibody binds to and activates receptors for TSH (a pituitary hormone that controls the production of the hormone thyroxine by the thyroid). Graves disease is not caused by increased levels of circulating immunoglobulins, infiltration of the thyroid by T lymphocytes, or by exposure to acetylates.

Once they have penetrated the first line of defense, which microorganisms do natural killer (NK) cells actively attack? a. Bacteria b. Fungi c. Viruses d. Mycoplasma

ANS: C NK cells are the principal defenders against only tumor cells or virally infected cells.

13. The action of which hormone helps explain increases in affective anxiety and eating disorders, mood cycles, and vulnerability to autoimmune and inflammatory diseases in women as a result of stimulation of the CRH gene promoter and central norepinephrine system? a. Progesterone b. Cortisol c. Estrogen d. Prolactin

ANS: C Of the options provided, only estrogen directly stimulates the CRH gene promoter and the central noradrenergic (norepinephrine) system, which may help explain adult women's slight hypercortisolism, increases in affective anxiety and eating disorders, mood cycles, and vulnerability to autoimmune and inflammatory disease, all of which follow estradiol fluctuations.

11. A severely stressed patient has hypoglycemia each time the patient's blood glucose is checked. The healthcare professional should order laboratory tests to measure which hormone in the patient's blood? a. Epinephrine b. Norepinephrine c. Cortisol d. Growth hormone

ANS: C One of the primary effects of cortisol is the stimulation of gluconeogenesis or the formation of glucose from noncarbohydrate sources, such as amino or free fatty acids in the liver. Neither reaction is a result of the effects of any of the other hormones.

9. Released stress-induced cortisol results in the stimulation of gluconeogenesis by affecting which structure? a. Adrenal cortex b. Pancreas c. Liver d. Anterior pituitary

ANS: C One of the primary effects of cortisol is the stimulation of gluconeogenesis through stimulation of the liver. The adrenal cortex, pancreas, and anterior pituitary do not produce stimulation of gluconeogenesis when exposed to cortisol.

31. A student asks the healthcare professional how the aging process of the T-cell activity affects older adults. What response by the professional is best? a. Poor heat regulation abilities b. Increased risk for bone fractures c. Tendency to develop various infections d. Likelihood of experiencing benign skin lesions

ANS: C T-cell activity is deficient in older adults, and a shift in the balance of T-cell subsets is observed. These changes may result in increased susceptibility to infection. The other issues are not related to T-cell activity.

19. Th2 cells produce IL-4 and suppress which cells? a. B lymphocytes b. Cytotoxic T lymphocytes c. Th1 cells d. Memory T lymphocytes

ANS: C Th2 cells produce IL-4, which suppresses only Th1 and Th17 cells through their IL-4 receptors.

13. An individual is more susceptible to infections of mucous membranes when he or she has a seriously low level of which immunoglobulin antibody? a. IgG b. IgM c. IgA d. IgE

ANS: C The IgA molecules found in bodily secretions are dimers anchored together through a J-chain and secretory piece. This secretory piece is attached to the IgA antibodies inside the mucosal epithelial cells and may function to protect these immunoglobulin antibodies against degradation by enzymes also found in the secretions, thus decreasing the risk of infections in the mucous membrane. The other options do not accurately identify the immunoglobulin antibody involved in mucous membrane infections.

21. Tissue damage caused by the deposition of circulating immune complexes containing an antibody against the host DNA is the cause of which disease? a. Hemolytic anemia b. Pernicious anemia c. Systemic lupus erythematosus d. Myasthenia gravis

ANS: C The deposition of circulating immune complexes containing an antibody against the host DNA produces tissue damage in individuals with systemic lupus erythematosus (SLE). That is not a process in hemolytic anemia, pernicious anemia, or myasthenia gravis.

AIDS produces a striking decrease in the number of which cells? a. Macrophages b. CD8+ T cells c. CD4+ Th cells d. Memory T cells

ANS: C The major immunologic finding in AIDS is the striking decrease in the number of CD4+ Th cells (see Figure 10-15). This finding is not true of the other options.

3. During an anticipatory response to stress, what is the reaction from the limbic system stimulated by? a. The retronucleus of the anterior pituitary b. The anterior nucleus of the hippocampus c. The paraventricular nucleus of the hypothalamus d. The prefrontal nucleus of the amygdala

ANS: C The paraventricular nucleus (PVN) of the hypothalamus must be stimulated to cause the limbic system to be stimulated. The other areas are not involved in the stimulation of the limbic system.

5. Perceived stress elicits an emotional, anticipatory response that begins where? a. Prefrontal cortex b. Anterior pituitary c. Limbic system d. Hypothalamus

ANS: C The perception of stress initiates a series of events in the central and peripheral nervous systems. In the brain, stress elicits an anticipatory response that activates the limbic system; the brain area is responsible for motivation, emotions, and cognition.

6. The portion of the antigen that is configured for recognition and binding is referred to as what type of determinant? a. Immunotope b. Paratope c. Epitope d. Antigenitope

ANS: C The precise portion of the antigen that is configured for recognition and binding is called its antigenic determinant or epitope. The other terms are not discussed in the text.

7. Stress-induced sympathetic stimulation of the adrenal medulla causes the secretion of what? a. Epinephrine and aldosterone b. Norepinephrine and cortisol c. Epinephrine and norepinephrine d. Acetylcholine and cortisol

ANS: C The sympathetic nervous system is aroused during the stress response and causes the medulla of the adrenal gland to release catecholamines (80% epinephrine and 20% norepinephrine) into the bloodstream. Sympathetic stimulation of the adrenal medulla does not cause the secretion of aldosterone, cortisol, or acetylcholine.

16. A student is confused about the process of the generation of clonal diversity. What description by the professor is best? a. It involves antigens that select those lymphocytes with compatible receptors. b. It allows the differentiation of cells into antibody-secreting plasma cells or mature Peyer patches. c. It takes place in the primary (central) lymphoid organs. d. It causes antigens to expand and diversify their populations.

ANS: C This process occurs in central lymphoid organs—the thymus gland for T cells and bone marrow for B cells. It does not involve antigens selecting lymphocytes or expanding and diversifying. It does allow the differentiation of lymphoid stem cells into B and T lymphocytes. Payer patches are lymphoid organs found in the intestines.

16. A type IV hypersensitivity reaction causes which result? a. Antibodies coating mast cells by binding to receptors that signal its degranulation, followed by the discharge of preformed mediators b. Antibodies binding to soluble antigens that were released into body fluids and the immune complexes being deposited in the tissues c. Lymphokine-producing Th1 cells directly attacking and destroying cellular targets d. Antibodies binding to the antigen on the cell surface

ANS: C Type I, II, and III hypersensitivity reactions are mediated by antibody, type IV reactions are mediated by T lymphocytes and do not involve antibody. Type IV mechanisms occur through either Tc cells or lymphokine-producing Th1 cells. Tc cells directly attack and destroy cellular targets.

35. Which is an example of a bacterial toxin that has been inactivated but still retains its immunogenicity to protect the person? (Select all that apply.) a. Poliomyelitis b. Measles c. Tetanus d. Gonorrhea e. Diphtheria

ANS: C,E The symptoms of tetanus or diphtheria are mediated by specific toxins. To prevent harming the recipient of the immunization, bacterial toxins are chemically inactivated so that they have lost most of their harmful properties but still retain their immunogenicity. These agents are referred to as toxoids. Poliomyelitis, measles, and gonorrhea are not examples.

17. What is the most influential factor in whether a person will experience a stress reaction? a. General state of physical health b. Spiritual belief system c. Intellectual abilities d. Ability to cope

ANS: D A person does not have a stress reaction unless the stress exceeds his or her coping abilities. General health, spiritual belief systems, and intellectual abilities do not have the same degree of influence on stress reactions.

22. When a person is exposed to most antigens, antibodies can be usually detected in their circulation within what timeframe? a. 12 hours b. 24 hours c. 3 days d. 6 days

ANS: D After approximately 5 to 7 days is an IgM antibody specific for that antigen detected in the circulation.

33. Antibodies that are associated with mucosal immune system, such as immunoglobulins, function to prevent which type of infections? a. Infections that attack the respiratory system b. Infections that tend to be chronic in nature c. Infections likely to be resistant to antibiotics d. Infections that focus on epithelial surfaces of the body

ANS: D Antibodies of the systemic immune system function throughout the body, whereas antibodies of the secretory (mucosal) immune system—primarily immunoglobulins of the IgA class—are associated with bodily secretions and function to prevent pathogenic infection on epithelial surfaces. The other options are not necessarily true when considering the immunoglobulins.

8. A student asks why some vaccinations are given orally and some are given by injection. What response by the professor is best? a. Different routes allow the speed of onset of the antigen to be varied, with the intravenous route being the fastest. b. Some individuals appear to be unable to respond to an antigen by a specific route, thus requiring the availability of different routes for the same antigen. c. Antigen-presenting cells are highly specialized and thus require stimulation by different routes. d. Each route stimulates a different lymphocyte-containing tissue, resulting in different types of cellular and humoral immunity.

ANS: D Each route preferentially stimulates a different set of lymphocyte-containing (lymphoid) tissues and therefore results in the induction of different types of cell-mediated or humoral immune responses. The speed of onset of the antigen, individual differences in response, and the requirement for different routes to stimulate different antigen-presenting cells are not accurate descriptions of why different routes of immunization are used.

Which statement concerning exotoxins is true? a. Exotoxins are contained in cell walls of gram-negative bacteria. b. Exotoxins are released during the lysis of bacteria. c. Exotoxins are able to initiate the complement and coagulation cascades. d. Exotoxins are released during bacterial growth.

ANS: D Exotoxins are proteins released during bacterial growth. The other options are not true of exotoxins.

What is the final stage of the infectious process? a. Colonization b. Invasion c. Multiplication d. Spread

ANS: D From the perspective of the microorganisms that cause disease, the infectious process undergoes four separate stages of progression: (1) colonization, (2) invasion, (3) multiplication, and (4) spread.

26. Which component of the immune system is deficient in individuals with infections caused by viruses, fungi, or yeast? a. Natural killer cells b. Macrophages c. B cells d. T cells

ANS: D Of the available options, deficiencies in T-cell immune responses are suggested when certain viruses (e.g., varicella, vaccinia, herpes, cytomegalovirus), fungi, and yeasts (e.g., Candida, Histoplasma) or certain atypical microorganisms (e.g., Pneumocystis jiroveci) cause recurrent infections.

12. When soluble antigens from infectious agents enter circulation, what is tissue damage a result of? a. Complement-mediated cell lysis b. Phagocytosis by macrophages c. Phagocytosis in the spleen d. Neutrophil granules and toxic oxygen products

ANS: D Of the options available, only the components of neutrophil granules as well as the several toxic oxygen products produced by these cells, damage the tissue.

What is the role of reverse transcriptase in HIV infection? a. Reverse transcriptase converts single-stranded DNA into double-stranded DNA. b. It is needed to produce integrase. c. It transports the RNA into the cell nucleus. d. It converts RNA into double-stranded DNA.

ANS: D One particular family of viruses, retroviruses (e.g., HIV) carries an enzyme, reverse transcriptase, which creates a double-stranded DNA version of the virus.

Which disease is an example of a rickettsial infection? a. Cholera b. Candida c. Sleeping sickness d. Rocky Mountain spotted fever

ANS: D Rocky Mountain spotted fever is a result of a rickettsiae. Cholera is a bacterial infection, candida is a fungal infection, and sleeping sickness is a protozoal infection.

Some bacterial surface proteins bind with the crystalline fragment (Fc) portion of an antibody to: a. Hide in cells to avoid triggering an immune response b. Form self-protecting toxins c. Make staining possible for microscopic observation d. Produce a protective "self" protein

ANS: D Some bacterial surface proteins (protein A of Staphylococcus aureus, protein G of Streptococcus pyogenes) bind the Fc portion of the individual's antibody, thus forming a protective coat of "self" protein. The other options do not accurately define the role of bacterial surface proteins as they bind with the Fc portion on an antibody.

9. A student asks about the mechanism that results in type II hypersensitivity reactions. What description by the professor is best? a. Antibodies coat mast cells by binding to receptors that signal its degranulation, followed by a discharge of preformed mediators. b. Antibodies bind to soluble antigens that were released into body fluids, and the immune complexes are then deposited in the tissues. c. Cytotoxic T lymphocytes or lymphokine-producing helper T 1 cells directly attack and destroy cellular targets. d. Antibodies bind to the antigens on the cell surface.

ANS: D The mechanism that results in a type II hypersensitivity reaction begins with antibody binding to tissue-specific antigens or antigens that have attached to particular tissues. The cell can be destroyed by antibody IgG or IgM and activation of the complement cascade through the classical pathway.

13. How are target cells destroyed in a type II hypersensitivity reaction? a. Tissue damage from mast cell degranulation b. Antigen-antibody complexes deposited in vessel walls c. Cytotoxic T lymphocytes attack the cell directly. d. Natural killer cells

ANS: D The mechanism that results in a type II hypersensitivity reaction involves a subpopulation of cytotoxic cells that are not antigen specific (natural killer [NK] cells). Antibody on the target cell is recognized by Fc receptors on the NK cells, which releases toxic substances that destroy the target cell. Tissue damage from mast cell degranulation occurs in type I hypersensitivity reactions. Antigen-antibody complexes are active in type III hypersensitivity responses. Cytotoxic lymphocytes are involved in type IV hypersensitivity responses.

26. Which T cell controls or limits the immune response to protect the host's own tissues against an autoimmune response? a. Cytotoxic T cells b. Th1 cells c. Th2 cells d. Regulatory T (Treg) cells

ANS: D The regulatory T (Treg) cell's role is to control or limit the immune response to protect the host's own tissues against autoimmune reactions. Cytotoxic T cells attack and kill cellular targets directly. Th2 cells provide help for developing B cells and produce IL-4, IL-5, IL-6, and IL-13. Th1 cells are induced by antigens derived from cancer cells.

14. How does the B-cell receptor (BCR) complex function? a. Communicating information about the antigen to the helper T cell b. Secreting chemical signals to communicate between cells c. Releasing histamine and other vasoactive substances d. Communicating information about the antigen to the cell nucleus

ANS: D The role of the BCR is to recognize the antigen; however, unlike circulating antibodies, the receptor must communicate that information to the cell's nucleus. The BCR does not communicate information about the antigen to the helper T cell or secrete chemical signals to communicate between cells. The release of histamine and other vasoactive substances is part of inflammation, not adaptive immunity.

Which organism is a common sexually transmitted bacterial infection? a. Staphylococcus aureus b. Clostridium perfringens c. Helicobacter pylori d. Treponema pallidum

ANS: D Treponema pallidum (spirochete, syphilis) is a sexually transmitted disease. Staphylococcus aureus is commonly ingested, causing food poisoning; Clostridium perfringens (gas gangrene) is a skin or wound infection; and Helicobacter pylori (gastritis, peptic ulcers) is found in the gastrointestinal tract.

24. A person with type O blood needs a blood transfusion. What blood type does the healthcare professional prepare to administer to the patient? a. A b. B c. AB d. O

ANS: D Type O individuals have neither A or B antigen but have both anti-A and anti-B antibodies and therefore cannot accept blood from any of the other three types. The healthcare professional would prepare to administer a transfusion of type O blood.

30. Urticaria is a manifestation of a which type of hypersensitivity reaction? a. IV b. III c. II d. I

ANS: D Urticaria, or hives, is a dermal (skin) manifestation of only type I allergic reactions.

Which is an example of an alloimmune disease? a. Tuberculin reaction b. Graves disease c. Contact dermatitis d. Penicillin allergy

B Graves disease is a classic autoimmune, or alloimmune, disease. Tuberculin reaction is a type IV reaction. Contact dermatitis is a type I reaction. Penicillin is an allergen that induces type I hypersensitivity.

It is true that immunoglobulin E (IgE) is a. designed to protect the host from large viruses. b. the primary cause of common allergies. c. the only inflammatory cell that can damage a virus. d. normally found at high concentrations in the circulation.

B IgE, a mediator of common allergic responses, is an antibody that is designed to protect the host from parasites and is the only inflammatory cell that can damage a parasite. IgE is normally found in low concentrations in the circulation.

Which is a function of norepinephrine? a. Increases contraction of the heart b. Constricts smooth muscle in all blood vessels c. Secretes steroid hormones d. Stimulates adrenal medulla

B Norepinephrine is released from the adrenal medulla and regulates blood pressure by constricting smooth muscle in all blood vessels. Epinephrine increases myocardial contractility and heart rate. The steroid hormones are stimulated by the hypothalamus, which sets off a chain of events during which steroid hormones are secreted from the adrenal cortex. Cortisol is one of the primary steroid hormones.

What is the precise portion of the antigen that is configured for recognition and binding of an antibody? a. Paratope b. Epitope c. Self-antigen d. Immunogen

B The antigenic determinant or epitope is the precise portion of the antigen that is configured for recognition and binding of an antibody. A paratope is the matching portion on the antibody or lymphocyte receptor. A self-antigen is one that is not foreign to the host. An immunogen is an antigen that induces an immune response.

What is the definition of the reactive response? a. Mounting a response in anticipation of a stressor b. Mounting a response in reaction to a psychologic stressor c. Mounting a response to a learned stressor d. Mounting a response to a physical stressor

B A reactive response is a psychologic response to a stressor. An anticipatory response is a psychologic response to an anticipated response. A conditioned response is an anticipated psychologic (learned) response to stimuli that have been associated with danger.

Which statement is true regarding stress and the immune system? a. Seasonal allergies are related to stress. b. Cardiovascular disease is one condition that is related to stress. c. The level of proinflammatory cytokines is decreased. d. Negative emotions cause few alterations in cytokine production.

B Cardiovascular disease, aging, cancer, osteoporosis, arthritis, type II diabetes mellitus, and chronic obstructive pulmonary disease (COPD) are associated with the prolonged presence of proinflammatory cytokines. These proinflammatory cytokines increase during stress. Negative emotions are directly associated with the increased level of these proinflammatory cytokines.

Which statement best describes a type I reaction? a. Most type I reactions are mediated by IgA. b. Most type I reactions are allergic. c. Most occur against medications. d. Rarely does this type of reaction contribute to autoimmune diseases.

B Most type I reactions are allergic. They are mediated by IgE. Most type I reactions occur against environmental antigens and can contribute to some autoimmune diseases.

Which are molecular classes of immunoglobulins? (Select all that apply.) a. IgC b. IgD c. IgE d. IgM e. IgN

B,C,D The five classes of immunoglobulin are IgG, IgA, IgM, IgD, and IgE.

Which statement is true regarding atopic individuals? a. If one parent has allergies, then a 4% chance exists that the offspring will have similar allergies. b. If two parents have allergies, then a 50% chance exists that their offspring will have similar allergies. c. Atopic individuals tend to produce higher quantities of IgE. d. No genes are associated with an atopic state.

C Higher quantities of IgE are present in atopic individuals. If one parent has an allergy, then the individual has a 40% of having allergies; with two parents, the individual has an 80% of having allergies. Multiple genes have been associated with the atopic state.

Which statement best describes the cells and their functions in the humoral arm of the immune system? a. Cells undergo differentiation and develop into subpopulations. b. Cells attack cancerous cells. c. Antibodies are primarily responsible for protection. d. Cells in the humoral arm are also called cellular immunity.

C Antibodies are primarily responsible for protection against viruses and bacteria and are part of the humoral arm of the immune system. The antibody can directly invade a microorganism or activate the immune response. T cells undergo differentiation, attack cancerous cells, and are part of cellular immunity.

Which statement is true regarding how cortisol reacts when activated by ACTH? a. Cortisol is plasma bound to corticotropin. b. Gluconeogenesis is halted. c. Cortisol increases blood glucose. d. Cortisol decreases protein synthesis.

C Cortisol has many actions. It is bound to a protein called transcortin. It stimulates gluconeogenesis, increases glucose production, and increases protein synthesis.

Which statement is true regarding aging and the immune system function? a. Older adults have decreased circulating antibodies. b. T-cell function is increased. c. Antibody production to specific antigens is inferior. d. Response to infection is rapid.

C T-cell function is decreased, and immune responses are delayed. B-cell production is inferior; however, the cells have increased circulating antibody levels.

The Arthus reaction is an example of which type of sensitivity reaction? a. I b. II c. III d. IV

C The Arthus reaction is a type III hypersensitivity reaction.

Which statement is true regarding immunoglobulin A (IgA) antibodies? a. IgA-2 is predominantly found in blood. b. IgA-1 is predominantly found in the body's secretions. c. The J chain anchors together the IgA molecules. d. IgA is the most predominant immunoglobulin.

C The J chain anchors together the IgA molecules to form dimers and helps them resist degradation from enzymes. IgA-1 is found in the blood, and IgA-2 is found in the secretions of the body. IgG, not IgA, is the most predominant immunoglobulin.

Which statement is true regarding unmatched packed red blood cell (RBC) transfusions? a. Only three different RBC antigens have been identified. b. Approximately 80 major carbohydrate antigens exist. c. People with O type blood have neither A or B antigens. d. A person with type A blood contains anti-O antibodies.

C Type O blood does not contain type A or B antigens. However, 80 major different RBC antigens are present. A person with type A blood carries anti-B antibodies and a person with type B blood carries anti-A antibodies. Those with type O blood have anti-A and anti-B antibodies.

A substance that is recognized as foreign or nonself is a. immunoglobulins. b. lymphocytes. c. antibodies. d. antigens.

D Antigens are recognized as foreign and initiate the immune response. Immunoglobulins and antibodies are part of the adaptive immune response; they attack the antigen. Lymphocytes are a type of blood cell that is part of the adaptive response.

Which statement is true regarding the immune system in response to stress? a. T-helper 1 (Th1) cells increase. b. A shift in Th1 cells occurs. c. The immune system is not affected. d. Cortisol is released.

D Stress can activate an excessive immune response through cortisol. It can cause the suppression of Th1 cells and a shift in Th2 cells.

Which statement is true regarding the effects of circulating epinephrine in the body? a. The heart rate will slow down. b. The heart's contractility will decrease. c. Blood vessels to skeletal muscle will constrict. d. Transient hyperglycemia will result.

D Epinephrine dilates blood vessels of the muscles and causes transient hyperglycemia. The epinephrine will increase heart rate and contractility. The venous return to the heart will increase, thus increasing cardiac output and blood pressure.

Which statement is true regarding the immune response in humans? a. Before birth, lymphocytes are not produced. b. B lymphocytes come from the thymus. c. The thymus releases mature lymphocytes. d. Generation of clonal diversity occurs in primary lymphoid organs.

D Generation of clonal diversity occurs in the primary lymphoid organs, which includes the thymus (T lymphocytes) and bone marrow (B lymphocytes). In the fetus, lymphocytes undergo extensive differentiation and proliferation that recognize almost any foreign antigen predominate. The thymus releases immature T cells that have the ability to recognize foreign antigens.

Which statement is true regarding a type IV allergic reaction? a. Is immediate in its action b. Is infiltrated with B cells c. Is mediated by antibody production d. Can be transferred by cells

D Type IV hypersensitivity reactions can be transferred by cells but not by serum. Their actions are delayed because their onset takes from 24 to 72 hours. The site is infiltrated with T lymphocytes and macrophages. A clear hard center surrounds the erythema (redness).