Exam (elaborations)

NR507 Week 4 Midterm Exam / NR 507 Week 4 Midterm Exam (2020, 2019, 5 Versions):Chamberlain University

NR507 Week 4 Midterm Exam / NR 507 Week 4 Midterm Exam (2020, 2019, 5 Versions):Chamberlain University NR 507 Week 4 Midterm 1. Question : What is the final stage of the infectious process? Colonization Invasion Multiplication Spread Explanation: 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. Question 2. Question : Where in the respiratory tract do the majority of foreign objects aspirated by children finally lodge? Trachea Left lung Bronchus Bronchioles Explanation: Approximately 75% of aspirated foreign bodies lodge in a bronchus. The other options are not locations where children aspirate the majority of foreign objects. Question 3. Question : What is the primary cause of respiratory distress syndrome (RDS) of the newborn? Immature immune system Small alveoli Surfactant deficiency Anemia Explanation: RDS is primarily caused by surfactant deficiency and secondarily by a deficiency in alveolar surface area for gas exchange. None of the other options are related to the cause of RDS. Question 4. Question : Which statement concerning benign tumors is true? The resulting pain is severe. Benign tumors are not encapsulated. Benign tumors are fast growing. The cells are well-differentiated. Explanation: A benign tumor is well-differentiated with its tissue appearing similar to the tissue from which it arose. The other options are characteristic of a malignant tumor. Question 5. Question : Which compensatory mechanism is spontaneously used by children diagnosed with tetralogy of Fallot to relieve hypoxic spells? Lying on their left side Performing the Valsalva maneuver Squatting Hyperventilating Explanation: Squatting is a spontaneous compensatory mechanism used by older children to alleviate hypoxic spells. Squatting and its variants increase systemic resistance while decreasing venous return to the heart from the inferior vena cava. The other options would not result in these changes. Question 6. Question : Which cytokines initiate the production of corticotropin-releasing hormone (CRH)? IL–1 and IL-6 IL-2 and TNF- IFN and IL-12 TNF-ß and IL-4 Explanation: 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. Question 7. Question : Hemolytic disease of the newborn (HDN) can occur if the mother: Is Rh-positive and the fetus is Rh-negative Is Rh-negative and the fetus is Rh-positive Has type A blood and the fetus has type O Has type AB blood and the fetus has type B Explanation: HDN can occur only if antigens on fetal erythrocytes differ from antigens on maternal erythrocytes. Maternal-fetal incompatibility exists only if the mother and fetus differ in ABO blood type or if the fetus is Rh-positive and the mother is Rh-negative. This erythrocyte incompatibility does not exist in any of the other options. Question 8. Question : Decreased lung compliance means that the lungs are demonstrating which characteristic? Difficult deflation Easy inflation Stiffness Inability to diffuse oxygen Explanation: A decrease in compliance indicates that the lungs or chest wall is abnormally stiff or difficult to inflate. This selection is the only option that accurately identifies the meaning of decreased compliance. Question 9. Question : Which statement concerning exotoxins is true? Exotoxins are contained in cell walls of gram-negative bacteria. Exotoxins are released during the lysis of bacteria. Exotoxins are able to initiate the complement and coagulation cascades. Exotoxins are released during bacterial growth. Explanation: Exotoxins are proteins released during bacterial growth. The other options are not true of exotoxins. Question 10. Question : What is the ratio of coronary capillaries to cardiac muscle cells? 1:1 (one capillary per one muscle cell) 1:2 (one capillary per two muscle cells) 1:4 (one capillary per four muscle cells) 1:10 (one capillary per ten muscle cells) Explanation: The heart has an extensive capillary network, with approximately 3300 capillaries per square millimeter (camm2) or approximately one capillary per one muscle cell (muscle fiber). Question 11. Question : How high does the plasma glucose have to be before the threshold for glucose is achieved? 126 mgdl 150 mgdl 180 mgdl 200 mgdl Explanation: When the plasma glucose reaches 180 mgdl, as occurs in the individual with uncontrolled diabetes mellitus, the threshold for glucose is achieved. Question 12. Question : What is the chief predisposing factor for respiratory distress syndrome (RDS) of the newborn? Low birth weight Alcohol consumption during pregnancy Premature birth Smoking during pregnancy Explanation: RDS of the newborn, also known as hyaline membrane disease (HMD), is a major cause of morbidity and mortality in premature newborns. None of the other options are considered the chief predisposing factors for RDS. Question 13. Question : Perceived stress elicits an emotional, anticipatory response that begins where? Prefrontal cortex Anterior pituitary Limbic system Hypothalamus Explanation: Perceived stressors elicit an anticipatory response that begins in the limbic system of the brain, the only option responsible for emotions and cognition. Question 14. Question : Causes of hyperkalemia include: Hyperparathyroidism and malnutrition Vomiting and diarrhea Renal failure and Addison disease Hyperaldosteronism and Cushing disease Explanation: Hyperkalemia should be investigated when a history of renal disease, massive trauma, insulin deficiency, Addison disease, use of potassium salt substitutes, or metabolic acidosis exists. The other options are not known to be causes of hyperkalemia. Question 15. Question : Between which months of age does sudden infant death syndrome (SIDS) most often occur? 0 and 1 2 and 4 5 and 6 6 and 7 Explanation: The incidence of SIDS is low during the first month of life but sharply increases in the second month of life, peaking at 2 to 4 months and is unusual after 6 months of age. Question 16. Question : What is the fundamental physiologic manifestation of anemia? Hypotension Hyperesthesia Hypoxia Ischemia Explanation: The fundamental physiologic manifestation of anemia is a reduced oxygen-carrying capacity of the blood, resulting in tissue hypoxia. Question 17. Question : What is the life span of platelets (in days)? 10 30 90 120 Explanation: A platelet circulates for approximately 10 days and ages. Macrophages of the mononuclear phagocyte system, mostly in the spleen, remove platelets. Question 18. Question : What part of the kidney controls renal blood flow, glomerular filtration, and renin secretion? Macula densa Visceral epithelium Juxtaglomerular apparatus (JGA) Filtration slits Explanation: Control of renal blood flow, glomerular filtration, and renin secretion occur at the JGA. Together, the juxtaglomerular cells and macula densa cells form the JGA. The control of renal blood flow, glomerular filtration, and renin secretion is not directed by any of the other options. Question 19. Question : An infant has a loud, harsh, holosystolic murmur and systolic thrill that can be detected at the left lower sternal border that radiates to the neck. These clinical findings are consistent with which congenital heart defect? Atrial septal defect (ASD) Ventricular septal defect (VSD) Patent ductus arteriosus (PDA) Atrioventricular canal (AVC) defect Explanation: On physical examination, a loud, harsh, holosystolic murmur and systolic thrill can be detected at the left lower sternal border. The intensity of the murmur reflects the pressure gradient across the VSD. An apical diastolic rumble may be present with a moderate-to-large defect, reflecting increased flow across the mitral valve. The presentations of the other congenital heart defects are not consistent with the described symptoms. Question 20. Question : The coronary ostia are located in the: Left ventricle Aortic valve Coronary sinus Aorta Explanation: Coronary arteries receive blood through openings in the aorta, called the coronary ostia. Question 21. Question : The only surface inside the nephron where cells are covered with microvilli to increase the reabsorptive surface area is called the: Proximal convoluted tubules Distal tubules Ascending loop of Henle Descending loop of Henle Explanation: The only surface inside the nephron where the cells are covered with microvilli (a brush border) is called the proximal convoluted tubules. This proximal convoluted tubular lumen consists of one layer of cuboidal cells with a surface layer of microvilli that increases the reabsorptive surface area. Question 22. Question : The drug heparin acts in hemostasis by which processes? Inhibiting thrombin and antithrombin III (AT-III) Preventing the conversion of prothrombin to thrombin Shortening the fibrin strands to retract the blood clot Degrading the fibrin within blood clots Explanation: Clinically administered heparin or heparin sulfate (on the surface of endothelial cells) binds to AT-III and induces a conformational change that greatly enhances its activity. Under normal conditions, the presence of endothelial cell heparin sulfate and available AT-III in the circulation cooperate to protect the vessels from the effects of spontaneously activated thrombin. The other options do not accurately describe the role heparin plays in hemostasis. Question 23. Question : Which immunoglobulin (Ig) is present in childhood asthma? IgM IgG IgE IgA Explanation: Included in the long list of asthma-associated genes are those that code for increased levels of immune and inflammatory mediators (e.g., interleukin [IL]–4, IgE, leukotrienes), nitric oxide, and transmembrane proteins in the endoplasmic reticulum. None of the other options are associated with childhood asthma. Question 24. Question : Immunoglobulin E (IgE) is associated with which type of hypersensitivity reaction? I II III IV Explanation: 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. Question 25. Question : Which organ is stimulated during the alarm phase of the general adaptation syndrome (GAS)? Adrenal cortex Hypothalamus Anterior pituitary Limbic system Explanation: The alarm phase of the GAS begins when a stressor triggers the actions of the hypothalamus and the sympathetic nervous system (SNS) (see Figure 11-1). The other organs are not stimulated by the alarm phase of GAS. Question 26. Question : Which congenital heart defects occur in trisomy 13, trisomy 18, and Down syndrome? Coarctation of the aorta (COA) and pulmonary stenosis (PS) Tetralogy of Fallot and persistent truncus arteriosus Atrial septal defect (ASD) and dextrocardia Ventricular septal defect (VSD) and patent ductus arteriosus (PDA) Explanation: Congenital heart defects that are related to dysfunction of trisomy 13, trisomy 18, and Down syndrome include VSD and PDA (see Table 33-2). The other defects are not associated with dysfunction of trisomy 13, trisomy 18, and Down syndrome. Question 27. Question : What substance stimulates renal hydroxylation in the process of producing vitamin D? Erythropoietin Thyroid hormone Calcitonin Parathyroid hormone Explanation: Parathyroid hormone stimulates renal hydroxylation in the process of producing vitamin D. The first step occurs in the liver with hydroxylation at the 25th carbon (calcifediol); the second step in hydroxylation occurs at the first carbon position in the kidneys. The other options are not involved in this process. Question 28. Question : Which term is used to identify the movement of gas and air into and out of the lungs? Perfusion Ventilation Respiration Diffusion Explanation: Of the options available, ventilation is the only term used to identify the mechanical movement of gas or air into and out of the lungs. Question 29. Question : Where are antibodies produced? Helper T lymphocytes Thymus gland Plasma cells Bone marrow Explanation: An antibody or immunoglobulin is a serum glycoprotein produced only by plasma cells in response to a challenge by an immunogen. Question 30. Question : What is the most common cause of insufficient erythropoiesis in children? Folic acid deficiency Iron deficiency Hemoglobin abnormality Erythrocyte abnormality Explanation: Similar to the anemias of adulthood, ineffective erythropoiesis or premature destruction of erythrocytes causes the anemias of childhood. The most common cause of insufficient erythropoiesis is iron deficiency. The other options may be causes but are not common ones. Question 31. Question : In a normal, nonmutant state, an oncogene is referred to as a: Basal cell Target cell Caretaker gene Proto-oncogene Explanation: In its normal nonmutant state, an oncogene is referred to as a proto-oncogene. The other options are not terms used to identify a nonmutant oncogene. Question 32. Question : Which manifestations of vasoocclusive crisis are associated with sickle cell disease (SCD) in infants? Atelectasis and pneumonia Edema of the hands and feet Stasis ulcers of the hands, ankles, and feet Splenomegaly and hepatomegaly Explanation: Symmetric, painful swelling of the hands and feet (hand-foot syndrome) caused by infarction in the small vessels of the extremities is often the initial manifestation of SCD in infants. This selection is the only option that accurately identifies the manifestations of a vasoocclusive crisis associated with SCD in infancy. Question 33. Question : What is the life span of an erythrocyte (in days)? 20 to 30 60 to 90 100 to 120 200 to 240 Explanation: Because it cannot undergo mitotic division, the erythrocyte has a limited life span of approximately 120 days. Question 34. Question : Which term is used to describe a muscle cell showing a reduced ability to form new muscle while appearing highly disorganized? Dysplasia Hyperplasia Myoplasia Anaplasia Explanation: Anaplasia is defined as the loss of cellular differentiation, irregularities of the size and shape of the nucleus, and the loss of normal tissue structure. In clinical specimens, anaplasia is recognized by a loss of organization and a significant increase in nuclear size with evidence of ongoing proliferation. The remaining options refer to specific changes in the cell. Question 35. Question : Which hepatitis virus is known to be sexually transmitted? A B C D Explanation: Only hepatitis B virus (HBV) is known to be sexually transmitted. Question 36. Question : What is the primary problem resulting from respiratory distress syndrome (RDS) of the newborn? Consolidation Pulmonary edema Atelectasis Bronchiolar plugging Explanation: The primary problem is atelectasis, which causes significant hypoxemia and is difficult for the neonate to overcome because a significant negative inspiratory pressure is required to open the alveoli with each breath. None of the other options are considered a primary problem associated with RDS. Question 37. Question : What is the action of urodilatin? Urodilatin causes vasoconstriction of afferent arterioles. It causes vasodilation of the efferent arterioles. Urodilatin inhibits antidiuretic hormone secretion. It inhibits salt and water reabsorption. Explanation: Urodilatin (a natriuretic peptide) inhibits sodium and water reabsorption from the medullary part of collecting duct, thereby producing diuresis. It is not involved in the actions described by the other options. Question 38. Question : Erythrocyte life span of less than 120 days, ineffective bone marrow response to erythropoietin, and altered iron metabolism describe the pathophysiologic characteristics of which type of anemia? Aplastic Sideroblastic Anemia of chronic disease Iron deficiency Explanation: Anemia of chronic disease results from a combination of (1) decreased erythrocyte life span, (2) suppressed production of erythropoietin, (3) ineffective bone marrow erythroid progenitor response to erythropoietin, and (4) altered iron metabolism and iron sequestration in macrophages. This result is not true of the other options. Question 39. Question : The function of the foramen ovale in a fetus allows what to occur? Right-to-left blood shunting Left-to-right blood shunting Blood flow from the umbilical cord Blood flow to the lungs Explanation: The nonfused septum secundum and ostium secundum result in the formation of a flapped orifice known as the foramen ovale, which allows the right-to-left shunting necessary for fetal circulation. The foramen ovale is not involved in the blood flow described by the other options. Question 40. Question : What is the most abundant class of plasma protein? Globulin Albumin Clotting factors Complement proteins Explanation: Albumin (approximately 60% of total plasma protein at a concentration of about 4 gdl) is the most abundant plasma protein. Question 41. Question : When a patient has small, vesicular lesions that last between 10 and 20 days, which sexually transmitted infection is suspected? Genital herpes Chancroid Syphilis Chlamydia Explanation: If symptoms occur, the individual may have small (1 to 2 mm), multiple, vesicular lesions that are generally located on the labia minora, fourchette, or penis. They may also appear on the cervix, buttocks, and thighs and are often painful and pruritic. These lesions usually last approximately 10 to 20 days. The other options do not demonstrate these symptoms. Question 42. Question : During an IgE-mediated hypersensitivity reaction, which leukocyte is activated? Neutrophils Monocytes Eosinophils T lymphocytes Explanation: Of the options provided, only eosinophils are activated during IgE-mediated hypersensitivity reactions. Question 43. Question : What effect do natriuretic peptides have during heart failure when the heart dilates? Stimulates antidiuretic hormones. Inhibits antidiuretic hormones. Stimulates renin and aldosterone. Inhibits renin and aldosterone. Explanation: Natriuretic peptides inhibit renin and aldosterone during heart failure when the heart dilates. These make up a group of peptide hormones, including atrial natriuretic peptide (ANP), secreted from myocardial cells in the atria and brain natriuretic peptide (BNP) secreted from myocardial cells in the cardiac ventricles. When the heart dilates during volume expansion or heart failure, ANP and BNP inhibit sodium and water absorption by kidney tubules, inhibit the secretion of renin and aldosterone, vasodilate the afferent arterioles, and constrict the efferent arterioles. The result is increased urine formation, leading to decreased blood volume and blood pressure. Question 44. Question : Blood vessels of the kidneys are innervated by the: Vagus nerve Sympathetic nervous system Somatic nervous system Parasympathetic nervous system Explanation: The blood vessels of the kidney are innervated by the sympathetic noradrenergic fibers that cause arteriolar vasoconstriction and reduce renal blood flow. The other options are not involved in this process. Question 45. Question : What is the first stage in the infectious process? Invasion Colonization Spread Multiplication Explanation: 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. Question 46. Question : Which drug may be prescribed orally for outbreak management of herpes simplex viral (HSV) infections? Acyclovir (Zovirax) 5-Fluorouracil (5-FU) Zidovudine (AZT) (Retrovir) Bichloroacetic acid (BCA) Explanation: Although no curative treatment for HSV infection is known, only oral acyclovir, valacyclovir, penciclovir, and famciclovir are used for primary and periodic outbreaks and to prevent recurrences. Question 47. Question : What is the most common cause of iron deficiency anemia (IDA)? Decreased dietary intake Chronic blood loss Vitamin deficiency Autoimmune disease Explanation: The most common cause of IDA in well-developed countries is pregnancy and chronic blood loss. Question 48. Question : Causes of hyperkalemia include: Hyperparathyroidism and malnutrition Vomiting and diarrhea Renal failure and Addison disease Hyperaldosteronism and Cushing disease Explanation: Hyperkalemia should be investigated when a history of renal disease, massive trauma, insulin deficiency, Addison disease, use of potassium salt substitutes, or metabolic acidosis exists. The other options are not known to be causes of hyperkalemia. Question 49. Question : A person with type O blood is considered to be the universal blood donor because type O blood contains which of the following? No antigens No antibodies Both A and B antigens Both A and B antibodies Explanation: 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. Question 50. Question : Which type of antibody is involved in type I hypersensitivity reaction? IgA IgE IgG IgM Explanation: Type I reactions are only mediated by antigen-specific IgE and the products of tissue mast cells (see Figure 9-1). Question 51. Question : Which cardiac chamber has the thinnest wall and why? The right and left atria; they are low-pressure chambers that serve as storage units and conduits for blood. The right and left atria; they are not directly involved in the preload, contractility, or afterload of the heart. The left ventricle; the mean pressure of blood coming into this ventricle is from the lung, which has a low pressure. The right ventricle; it pumps blood into the pulmonary capillaries, which have a lower pressure compared with the systemic circulation. Explanation: The two atria have the thinnest walls because they are low-pressure chambers that serve as storage units and conduits for blood that is emptied into the ventricles. This selection is the only option that correctly identifies which heart chambers have the thinnest walls and why that helps cardiac function. Question 52. Question : Which criterion is used to confirm a diagnosis of asthma in an 8-year-old child? Parental history of asthma Serum testing that confirms increased immunoglobulin E (IgE) and eosinophil levels Reduced expiratory flow rates confirmed by spirometry testing Improvement on a trial of asthma medication Explanation: Confirmation of the diagnosis of asthma relies on pulmonary function testing using spirometry, which can be accomplished only after the child is 5 to 6 years of age. Reduced expiratory flow rates that are reversible in response to an inhaled bronchodilator would be characteristic abnormalities. For younger children, an empiric trial of asthma medications is commonly initiated. The remaining options are major historical and physical factors that contribute but do not confirm the diagnosis of asthma in children. Question 53. Question : The lung is innervated by the parasympathetic nervous system via which nerve? Vagus Phrenic Brachial Pectoral Explanation: Fibers of the parasympathetic division of the autonomic nervous system (ANS) travel only in the vagus nerve to the lung. Question 54. Question : The generation of clonal diversity occurs primarily during which phase of life? Fetal Neonatal Infancy Puberty Explanation: Generation of clonal diversity primarily occurs in the fetus and probably continues to a low degree throughout most of adult life. Question 55. Question : What is the role of collagen in the clotting process? Initiates the clotting cascade. Activates platelets. Stimulates fibrin. Deactivates fibrinogen. Explanation: In the clotting process, collagen provides a particularly strong stimulus to activate platelets. Collagen does not bring about any of the other options. Question 56. Question : What physical sign is the result of turbulent blood flow through a vessel? Increased blood pressure during periods of stress Bounding pulse felt on palpation Cyanosis observed on excretion Murmur heard on auscultation Explanation: Where flow is obstructed, the vessel turns or blood flows over rough surfaces. The flow becomes turbulent with whorls or eddy currents that produce noise, causing a murmur to be heard on auscultation, such as occurs during blood pressure measurement with a sphygomanometer. This selection is the only option that accurately identifies the physical sign of turbulent vascular blood flow. Question 57. Question : The most common site of metastasis for a patient diagnosed with prostate cancer is which location? Bones Brain Bladder Kidney Explanation: The bone, especially the lumbar spine area, is the most common metastasis site for prostate cancer. Question 58. Question : What is the direct action of atrial natriuretic hormone? Sodium retention Sodium excretion Water retention Water excretion Explanation: Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) inhibit the secretion of renin, inhibit angiotensin-induced secretion of aldosterone, vasodilate the afferent and constrict the efferent glomerular arterioles, and inhibit sodium and water absorption by kidney tubules. The other actions are not a result of the atrial natriuretic hormone. Question 59. Question : Continuous increases in left ventricular filing pressures result in which disorder? Mitral regurgitation Mitral stenosis Pulmonary edema Jugular vein distention Explanation: Pressure changes are important because increased left ventricular filling pressures back up into the pulmonary circulation, where they force plasma out through vessel walls, causing fluid to accumulate in lung tissues (pulmonary edema). This selection is the only option that accurately identifies the disorder described in the question. Question 60. Question : Phagocytosis involves neutrophils actively attacking, engulfing, and destroying which microorganisms? Bacteria Fungi Viruses Yeasts Explanation: 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. NR 507 WEEK 4 MIDTERM Question 1. What physical sign is the result of turbulent blood flow through a vessel? Increased blood pressure during periods of stress Bounding pulse felt on palpation Cyanosis observed on excretion Murmur heard on auscultation Explanation: Where flow is obstructed, the vessel turns or blood flows over rough surfaces. The flow becomes turbulent with whorls or eddy currents that produce noise, causing a murmur to be heard on auscultation, such as occurs during blood pressure measurement with a sphygomanometer. This selection is the only option that accurately identifies the physical sign of turbulent vascular blood flow. Question 2. Which organism is a common sexually transmitted bacterial infection? Staphylococcus aureus Clostridium perfringens Helicobacter pylori Treponema pallidum Explanation: 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. Question 3. It has been determined that a tumor is in stage 2. What is the meaning of this finding? Cancer is confined to the organ of origin. Cancer has spread to regional structures. Cancer is locally invasive. Cancer has spread to distant sites Explanation: Cancer confined to the organ of origin is stage 1; cancer that is locally invasive is stage 2; cancer that has spread to regional structures, such as the lymph nodes, is stage 3; and cancer that has spread to distant sites, such as a liver cancer spreading to the lung or a prostate cancer spreading to bone, is stage 4. Question 4. Erythrocyte life span of less than 120 days, ineffective bone marrow response to erythropoietin, and altered iron metabolism describe the pathophysiologic characteristics of which type of anemia? Aplastic Sideroblastic Anemia of chronic disease Iron deficiency Explanation: Anemia of chronic disease results from a combination of (1) decreased erythrocyte life span, (2) suppressed production of erythropoietin, (3) ineffective bone marrow erythroid progenitor response to erythropoietin, and (4) altered iron metabolism and iron sequestration in macrophages. This result is not true of the other options. Question 5. When an individual aspirates food particles, where would the nurse expect to hear decreased or absent breath sounds? Left lung Right lung Trachea Carina Explanation: The right mainstem bronchus extends from the trachea more vertically than the left main bronchus; therefore aspirated fluids or foreign particles tend to enter the right lung rather than the left or any of the other locations listed. Question 6. What is the first stage in the infectious process? Invasion Colonization Spread Multiplication Explanation: 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. Question 7. Causes of hyperkalemia include: Hyperparathyroidism and malnutrition Vomiting and diarrhea Renal failure and Addison disease Hyperaldosteronism and Cushing disease Explanation: Hyperkalemia should be investigated when a history of renal disease, massive trauma, insulin deficiency, Addison disease, use of potassium salt substitutes, or metabolic acidosis exists. The other options are not known to be causes of hyperkalemia. Question 8. Which term is used to describe a muscle cell showing a reduced ability to form new muscle while appearing highly disorganized? Dysplasia Hyperplasia Myoplasia Anaplasia Explanation: Anaplasia is defined as the loss of cellular differentiation, irregularities of the size and shape of the nucleus, and the loss of normal tissue structure. In clinical specimens, anaplasia is recognized by a loss of organization and a significant increase in nuclear size with evidence of ongoing proliferation. The remaining options refer to specific changes in the cell. Question 9. The drug heparin acts in hemostasis by which processes? Inhibiting thrombin and antithrombin III (AT-III) Preventing the conversion of prothrombin to thrombin Shortening the fibrin strands to retract the blood clot Degrading the fibrin within blood clots Explanation: Clinically administered heparin or heparin sulfate (on the surface of endothelial cells) binds to AT-III and induces a conformational change that greatly enhances its activity. Under normal conditions, the presence of endothelial cell heparin sulfate and available AT-III in the circulation cooperate to protect the vessels from the effects of spontaneously activated thrombin. The other options do not accurately describe the role heparin plays in hemostasis. Question 10. What is the major concern regarding the treatment of gonococci infections? Development of antibiotic resistance Changes in virulence Changes in pathogenicity Mutations into different strains Explanation: Several types of drug-resistant strains have been identified; they are penicillinase-producing Neisseria gonorrhoeae (PPNG), which is resistant to penicillin; tetracycline-resistant N. gonorrhoeae (TRNG), which is resistant to tetracycline; chromosomal control of mechanisms of resistance of N. gonorrhoeae (CMRNG), which is resistant to penicillin and tetracycline; and increasingly a fluoroquinolone-resistant N. gonorrhoeae (QRNG). The other options are not major concerns. Question 11. What is the most common cause of insufficient erythropoiesis in children? Folic acid deficiency Iron deficiency Hemoglobin abnormality Erythrocyte abnormality Explanation: Similar to the anemias of adulthood, ineffective erythropoiesis or premature destruction of erythrocytes causes the anemias of childhood. The most common cause of insufficient erythropoiesis is iron deficiency. The other options may be causes but are not common ones. Question 12. What is the most abundant class of plasma protein? Globulin Albumin Clotting factors Complement proteins Explanation: Albumin(approximately 60% of total plasma protein at a concentration of about 4 gdl) is the most abundant plasma protein. Question 13. Decreased lung compliance means that the lungs are demonstrating which characteristic? Difficult deflation Easy inflation Stiffness Inability to diffuse oxygen Explanation: A decrease in compliance indicates that the lungs or chest wall is abnormally stiff or difficult to inflate. This selection is the only option that accurately identifies the meaning of decreased compliance. 0 of 2 Question 14. Which immunoglobulin (Ig) is present in childhood asthma? IgM IgG IgE IgA Explanation: Included in the long list of asthma-associated genes are those that code for increased levels of immune and inflammatory mediators (e.g., interleukin [IL]–4, IgE, leukotrienes), nitric oxide, and transmembrane proteins in the endoplasmic reticulum. None of the other options are associated with childhood asthma. Question 15. What is the functional unit of the kidney called? Glomerulus Nephron Collecting duct Pyramid Explanation: The nephronis the functional unit of the kidney. Although the other options are also located in the kidney, they are not its functional units. Question 16. An infant’s hemoglobin must fall below ___ gdl before signs of pallor, tachycardia, and systolic murmurs occur. 11 9 7 5 Explanation: When the hemoglobin falls below 5 gdl, pallor, tachycardia, and systolic murmurs may occur. Question 17. Why is nasal congestion a serious threat to young infants? Infants are obligatory nose breathers. Their noses are small in diameter. Infants become dehydrated when mouth breathing. Their epiglottis is proportionally greater than the epiglottis of an adult’s. Explanation: Infants up to 2 to 3 months of age are obligatory nose breathers and are unable to breathe in through their mouths. Nasal congestion is therefore a serious threat to a young infant. This selection is the only option that accurately describes why nasal congestion is a serious threat to young infants. Question 18. The risk for respiratory distress syndrome (RDS) decreases for premature infants when they are born between how many weeks of gestation? 16 and 20 20 and 24 24 and 30 30 and 36 Explanation: Surfactant is secreted into fetal airways between 30 and 36 weeks. The other options are not true regarding the timeframe when the risk for RDS decreases. Question 19. What effect do natriuretic peptides have during heart failure when the heart dilates? Stimulates antidiuretic hormones. Inhibits antidiuretic hormones. Stimulates renin and aldosterone. Inhibits renin and aldosterone. Explanation: Natriuretic peptides inhibit renin and aldosterone during heart failure when the heart dilates. These make up a group of peptide hormones, including atrial natriuretic peptide (ANP), secreted from myocardial cells in the atria and brain natriuretic peptide (BNP) secreted from myocardial cells in the cardiac ventricles. When the heart dilates during volume expansion or heart failure, ANP and BNP inhibit sodium and water absorption by kidney tubules, inhibit the secretion of renin and aldosterone, vasodilate the afferent arterioles, and constrict the efferent arterioles. The result is increased urine formation, leading to decreased blood volume and blood pressure. Question 20. Causes of hyperkalemia include: Hyperparathyroidism and malnutrition Vomiting and diarrhea Renal failure and Addison disease Hyperaldosteronism and Cushing disease Explanation: Hyperkalemia should be investigated when a history of renal disease, massive trauma, insulin deficiency, Addison disease, use of potassium salt substitutes, or metabolic acidosis exists. The other options are not known to be causes of hyperkalemia. Question 21. Examination of the throat in a child demonstrating signs and symptoms of acute epiglottitis may contribute to which life-threatening complication? Retropharyngeal abscess Laryngospasms Rupturing of the tonsils Gagging induced aspiration Explanation: Examination of the throat may trigger laryngospasm and cause respiratory collapse. Death may occur in a few hours. This selection is the only option that accurately identifies the life-threatening complication that can result from an examination of the throat of a child who demonstrates the signs and symptoms of acute epiglottitis. Question 22. When a patient has small, vesicular lesions that last between 10 and 20 days, which sexually transmitted infection is suspected? Genital herpes Chancroid Syphilis Chlamydia Explanation: If symptoms occur, the individual may have small (1 to 2 mm), multiple, vesicular lesions that are generally located on the labia minora, fourchette, or penis. They may also appear on the cervix, buttocks, and thighs and are often painful and pruritic. These lesions usually last approximately 10 to 20 days. The other options do not demonstrate these symptoms. Question 23. Which T-lymphocyte phenotype is the key determinant of childhood asthma? Cluster of differentiation (CD) 4 T-helper Th1 lymphocytes CD4 T-helper Th2 lymphocytes CD8 cytotoxic T lymphocytes Memory T lymphocytes Explanation: Asthma develops because the Th2 response (in which CD4 T-helper cells produce specific cytokines, such as interleukin [IL]–4, IL-5, and IL-13) promotes an atopic and allergic response in the airways. This selection is the only option that accurately identifies the appropriate T-lymphocyte phenotype. Question 24. How is most of the oxygen in the blood transported? Dissolved in plasma Bound to hemoglobin In the form of carbon dioxide (CO2) Bound to protein Explanation: Oxygen is transported in the blood in two forms. A small amount dissolves in plasma, and the remainder binds to hemoglobin molecules. The other options are not involved in this process. Question 25. What is the most common cause of iron deficiency anemia (IDA)? Decreased dietary intake Chronic blood loss Vitamin deficiency Autoimmune disease Explanation: The most common cause of IDA in well-developed countries is pregnancy and chronic blood loss. Question 26. In which primary immune deficiency is there a partial-to-complete absence of T-cell immunity? Bruton disease DiGeorge syndrome Reticular dysgenesis Adenosine deaminase deficiency Explanation: The principal immunologic defect in DiGeorge syndrome is the partial or complete absence of T-cell immunity. The other options are not the result of either a partial or complete absence of T-cell immunity. Question 27. Which complex (wave) represents the sum of all ventricular muscle cell depolarizations? PRS QRS QT interval P Explanation: Only the QRS complex represents the sum of all ventricular muscle cell depolarizations. Question 28. During an IgE-mediated hypersensitivity reaction, which leukocyte is activated? Neutrophils Monocytes Eosinophils T lymphocytes Explanation: Of the options provided, only eosinophils are activated during IgE-mediated hypersensitivity reactions. Question 29. What is the primary problem resulting from respiratory distress syndrome (RDS) of the newborn? Consolidation Pulmonary edema Atelectasis Bronchiolar plugging Explanation: The primary problem is atelectasis, which causes significant hypoxemia and is difficult for the neonate to overcome because a significant negative inspiratory pressure is required to open the alveoli with each breath. None of the other options are considered a primary problem associated with RDS. Question 30. Which substance has been shown to increase the risk of cancer when used in combination with tobacco smoking? Alcohol Steroids Antihistamines Antidepressants Explanation: Alcohol interacts with smoke, increasing the risk of malignant tumors, possibly by acting as a solvent for the carcinogenic chemicals in smoke products. No current research supports the remaining options as having an increased effect on the incidence of cancer when used in combination with tobacco smoking. Question 31. The only surface inside the nephron where cells are covered with microvilli to increase the reabsorptive surface area is called the: Proximal convoluted tubules Distal tubules Ascending loop of Henle Descending loop of Henle Explanation: The only surface inside the nephron where the cells are covered with microvilli (a brush border) is called the proximal convoluted tubules. This proximal convoluted tubular lumen consists of one layer of cuboidal cells with a surface layer of microvilli that increases the reabsorptive surface area. Question 32. Continuous increases in left ventricular filing pressures result in which disorder? Mitral regurgitation Mitral stenosis Pulmonary edema Jugular vein distention Explanation: Pressure changes are important because increased left ventricular filling pressures back up into the pulmonary circulation, where they force plasma out through vessel walls, causing fluid to accumulate in lung tissues (pulmonary edema). This selection is the only option that accurately identifies the disorder described in the question. Question 33. Apoptosis is a(an): Normal mechanism for cells to self-destruct when growth is excessive Antigrowth signal activated by the tumor-suppressor gene Rb Mutation of cell growth stimulated by the TP53 gene Transformation of cells from dysplasia to anaplasia Explanation: Normal cells have a mechanism that causes them to self-destruct when growth is excessive and cell cycle checkpoints have been ignored. Diverse stimuli, including normal development and excessive growth, trigger this self-destruct mechanism, called apoptosis. The remaining options do not describe apoptosis. Question 34. The function of the foramen ovale in a fetus allows what to occur? Right-to-left blood shunting Left-to-right blood shunting Blood flow from the umbilical cord Blood flow to the lungs Explanation: The nonfused septum secundum and ostium secundum result in the formation of a flapped orifice known as the foramen ovale, which allows the right-to-left shunting necessary for fetal circulation. The foramen ovale is not involved in the blood flow described by the other options. Question 35. If the sinoatrial (SA) node fails, then at what rate (depolarizations per minute) can the atrioventricular (AV) node depolarize? 60 to 70 40 to 60 30 to 40 10 to 20 Explanation: If the SA node is damaged, then the AV node will become the heart’s pacemaker at a rate of approximately 40 to 60 spontaneous depolarizations per minute. Question 36. Which cells have phagocytic properties similar to monocytes and contract like smooth muscles cells, thereby influencing the glomerular filtration rate? Principle cells Podocin cells Mesangial cells Intercalated cells Explanation: Mesangial cells and the mesangial matrix, secreted by mesangial cells, lie between and support the glomerular capillaries. Different mesangial cells contract like smooth muscle cells to regulate glomerular capillary blood flow. They also have phagocytic properties similar to monocytes. The other options are not capable of these functions. Question 37. An individual is more susceptible to infections of mucous membranes when he or she has a seriously low level of which immunoglobulin antibody? IgG IgM IgA IgE Explanation: 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. Question 38. The coronary ostia are located in the: Left ventricle Aortic valve Coronary sinus Aorta Explanation: Coronary arteries receive blood through openings in the aorta, called the coronary ostia. Question 39. What is the role of collagen in the clotting process? Initiates the clotting cascade. Activates platelets. Stimulates fibrin. Deactivates fibrinogen. Explanation: In the clotting process, collagen provides a particularly strong stimulus to activate platelets. Collagen does not bring about any of the other options. Question 40. Deficiencies in which element can produce depression of both B- and T-cell function? Iron Zinc Iodine Magnesium Explanation: Of the options available, only deficient zinc intake can profoundly depress T- and B-cell function. Question 41. What is the role of caretaker genes? Maintenance of genomic integrity Proliferation of cancer cells Secretion of growth factors Restoration of normal tissue structure Explanation: Caretaker genes are responsible for the maintenance of genomic integrity. The other options are not roles assumed by caretaker genes. Question 42. What is the chief predisposing factor for respiratory distress syndrome (RDS) of the newborn? Low birth weight Alcohol consumption during pregnancy Premature birth Smoking during pregnancy Explanation: RDS of the newborn, also known as hyaline membrane disease (HMD), is a major cause of morbidity and mortality in premature newborns. None of the other options are considered the chief predisposing factors for RDS. Question 43. Hemolytic disease of the newborn (HDN) can occur if the mother: Is Rh-positive and the fetus is Rh-negative Is Rh-negative and the fetus is Rh-positive Has type A blood and the fetus has type O Has type AB blood and the fetus has type B Explanation: HDN can occur only if antigens on fetal erythrocytes differ from antigens on maternal erythrocytes. Maternal-fetal incompatibility exists only if the mother and fetus differ in ABO blood type or if the fetus is Rh-positive and the mother is Rh-negative. This erythrocyte incompatibility does not exist in any of the other options. Question 44. Which congenital heart defects occur in trisomy 13, trisomy 18, and Down syndrome? Coarctation of the aorta (COA) and pulmonary stenosis (PS) Tetralogy of Fallot and persistent truncus arteriosus Atrial septal defect (ASD) and dextrocardia Ventricular septal defect (VSD) and patent ductus arteriosus (PDA) Explanation: Congenital heart defects that are related to dysfunction of trisomy 13, trisomy 18, and Down syndrome include VSD and PDA (see Table 33-2). The other defects are not associated with dysfunction of trisomy 13, trisomy 18, and Down syndrome. Question 45. Fetal hematopoiesis occurs in which structure? Gut Spleen Bone marrow Thymus Explanation: The spleen is the largest of the secondary lymphoid organs and the site of fetal hematopoiesis. Question 46. What is the final stage of the infectious process? Colonization Invasion Multiplication Spread Explanation: 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. Question 47. Which statement is true concerning the IgM? IgM is the first antibody produced during the initial response to an antigen. IgM mediates many common allergic responses. IgM is the most abundant class of immunoglobulins. IgM is capable of crossing the human placenta. Explanation: Typically, IgM is produced first (primary immune response), followed by IgG againstthe same antigen. The other options are not true statements regarding IgM. Question 48. Innervation of the bladder and internal urethral sphincter is supplied by which nerves? Peripheral nerves Parasympathetic fibers Sympathetic nervous system Tenth thoracic nerve roots Explanation: The innervation of the bladder and internal urethral sphincter is supplied by parasympathetic fibers of the autonomic nervous system. The process is not dependent on any of the other options. Question 49. Which statement best describes a Schilling test? Administration of radioactive cobalamin and the measurement of its excretion in the urine to test for vitamin B12 deficiency Measurement of antigen-antibody immune complexes in the blood to test for hemolytic anemia Measurement of serum ferritin and total iron-binding capacity in the blood to test for iron deficiency anemia Administration of folate and measurement in 2 hours of its level in a blood sample to test for folic acid deficiency anemia. Explanation: The Schilling test indirectly evaluates vitamin B12 absorption by administering radioactive B12 and measuring excretion in the urine. This selection is the only option that accurately describes a Schilling test. Question 50. Phagocytosis involves neutrophils actively attacking, engulfing, and destroying which microorganisms? Bacteria Fungi Viruses Yeasts Explanation: 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. Question 51. Which drug may be prescribed orally for outbreak management of herpes simplex viral (HSV) infections? Acyclovir (Zovirax) 5-Fluorouracil (5-FU) Zidovudine (AZT) (Retrovir) Bichloroacetic acid (BCA) Explanation: Although no curative treatment for HSV infection is known, only oral acyclovir, valacyclovir, penciclovir, and famciclovir are used for primary and periodic outbreaks and to prevent recurrences. Question 52. What is the ratio of coronary capillaries to cardiac muscle cells? 1:1 (one capillary per one muscle cell) 1:2 (one capillary per two muscle cells) 1:4 (one capillary per four muscle cells) 1:10 (one capillary per ten muscle cells) Explanation: The heart has an extensive capillary network, with approximately 3300 capillaries per square millimeter (camm2) or approximately one capillary per one muscle cell (muscle fiber). Question 53. Which disorder results in decreased erythrocytes and platelets with changes in leukocytes and has clinical manifestations of pallor, fatigue, petechiae, purpura, bleeding, and fever? Idiopathic thrombocytopenic purpura (ITP) Acute lymphocytic leukemia (ALL) Non-Hodgkin lymphoma (NHL) Iron deficiency anemia (IDA) Explanation: Pallor, fatigue, petechiae, purpura, bleeding, and fever are generally present with the most common symptoms reflecting the consequence of bone marrow failure, which results in decreased red blood cells and platelets and changes in white blood cells. This selection is the only option that correctly identifies the disease with the symptoms described. Question 54. What part of the kidney controls renal blood flow, glomerular filtration, and renin secretion? Macula densa Visceral epithelium Juxtaglomerular apparatus (JGA) Filtration slits Explanation: Control of renal blood flow, glomerular filtration, and renin secretion occur at the JGA. Together, the juxtaglomerular cells and macula densa cells form the JGA. The control of renal blood flow, glomerular filtration, and renin secretion is not directed by any of the other options. Question 55. Which manifestations of vasoocclusive crisis are associated with sickle cell disease (SCD) in infants? Atelectasis and pneumonia Edema of the hands and feet Stasis ulcers of the hands, ankles, and feet Splenomegaly and hepatomegaly Explanation: Symmetric, painful swelling of the hands and feet (hand-foot syndrome) caused by infarction in the small vessels of the extremities is often the initial manifestation of SCD in infants. This selection is the only option that accurately identifies the manifestations of a vasoocclusive crisis associated with SCD in infancy. Question 56. A person with type O blood is considered to be the universal blood donor because type O blood contains which of the following? No antigens No antibodies Both A and B antigens Both A and B antibodies Explanation: 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. Question 57. Which laboratory test is considered adequate for an accurate and reliable diagnosis of gonococcal urethritis in a symptomatic man? Ligase chain reaction (LCR) Gram-stain technique Polymerase chain reaction (PCR) DNA testing Explanation: Microscopic evaluation of Gram-stained slides of clinical specimens is deemed positive for Neisseria gonorrhoeae if gram-negative diplococci with the typical “kidney bean” morphologic appearance are found inside polymorphonuclear leukocytes. Such a finding is considered adequate for the diagnosis of gonococcal urethritis in a symptomatic man. The other options are not relevant to the diagnosis of this condition. Question 58. Which organ is stimulated during the alarm phase of the general adaptation syndrome (GAS)? Adrenal cortex Hypothalamus Anterior pituitary Limbic system Explanation: The alarm phase of the GAS begins when a stressor triggers the actions of the hypothalamus and the sympathetic nervous system (SNS) (see Figure 11-1). The other organs are not stimulated by the alarm phase of GAS. Question 59. Which type of antibody is involved in type I hypersensitivity reaction? IgA IgE IgG IgM Explanation: Type I reactions are only mediated by antigen-specific IgE and the products of tissue mast cells (see Figure 9-1). Question 60. Which type of immunity is produced by an individual after either natural exposure to the antigen or after immunization against the antigen? Passive-acquired immunity Active-acquired immunity Passive-innate immunity Active-innate immunity Explanation: 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. NR 507 WEEK 4 MIDTERM EXAM Question 1. Which substance has been shown to increase the risk of cancer when used in combination with tobacco smoking? Alcohol Steroids Antihistamines Antidepressants Explanation: Alcohol interacts with smoke, increasing the risk of malignant tumors, possibly by acting as a solvent for the carcinogenic chemicals in smoke products. No current research supports the remaining options as having an increased effect on the incidence of cancer when used in combination with tobacco smoking. Question 2. Which term is used to describe a muscle cell showing a reduced ability to form new muscle while appearing highly disorganized? Dysplasia Hyperplasia Myoplasia Anaplasia Explanation: Anaplasia is defined as the loss of cellular differentiation, irregularities of the size and shape of the nucleus, and the loss of normal tissue structure. In clinical specimens, anaplasia is recognized by a loss of organization and a significant increase in nuclear size with evidence of ongoing proliferation. The remaining options refer to specific changes in the cell. Question 3. What is the final stage of the infectious process? Colonization Invasion Multiplication Spread Explanation: 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. Question 4. What is the most common cause of insufficient erythropoiesis in children? Folic acid deficiency Iron deficiency Hemoglobin abnormality Erythrocyte abnormality Explanation: Similar to the anemias of adulthood, ineffective erythropoiesis or premature destruction of erythrocytes causes the anemias of childhood. The most common cause of insufficient erythropoiesis is iron deficiency. The other options may be causes but are not common ones. Question 5. Which statement is true concerning the IgM? IgM is the first antibody produced during the initial response to an antigen. IgM mediates many common allergic responses. IgM is the most abundant class of immunoglobulins. IgM is capable of crossing the human placenta. Explanation: Typically, IgM is produced first (primary immune response), followed by IgG against the same antigen. The other options are not true statements regarding IgM. Question 6. Where in the respiratory tract do the majority of foreign objects aspirated by children finally lodge? Trachea Left lung Bronchus Bronchioles Explanation: Approximately 75% of aspirated foreign bodies lodge in a bronchus. The other options are not locations where children aspirate the majority of foreign objects. Question 7. What is the role of caretaker genes? Maintenance of genomic integrity Proliferation of cancer cells Secretion of growth factors Restoration of normal tissue structure Explanation: Caretaker genes are responsible for the maintenance of genomic integrity. The other options are not roles assumed by caretaker genes. Question 8. During an IgE-mediated hypersensitivity reaction, which leukocyte is activated? Neutrophils Monocytes Eosinophils T lymphocytes Explanation: Of the options provided, only eosinophils are activated during IgE-mediated hypersensitivity reactions. Question 9. When a patient has small, vesicular lesions that last between 10 and 20 days, which sexually transmitted infection is suspected? Genital herpes Chancroid Syphilis Chlamydia Explanation: If symptoms occur, the individual may have small (1 to 2 mm), multiple, vesicular lesions that are generally located on the labia minora, fourchette, or penis. They may also appear on the cervix, buttocks, and thighs and are often painful and pruritic. These lesions usually last approximately 10 to 20 days. The other options do not demonstrate these symptoms. Question 10. What is the action of urodilatin? Urodilatin causes vasoconstriction of afferent arterioles. It causes vasodilation of the efferent arterioles. Urodilatin inhibits antidiuretic hormone secretion. It inhibits salt and water reabsorption. Explanation: Urodilatin (a natriuretic peptide) inhibits sodium and water reabsorption from the medullary part of collecting duct, thereby producing diuresis. It is not involved in the actions described by the other options. Question 11. Immunoglobulin E (IgE) is associated with which type of hypersensitivity reaction? I II III IV Explanation: 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. Question 12. What is the life span of platelets (in days)? 10 30 90 120 Explanation: A platelet circulates f