MLT ASCP Practice Questions 3.15.16

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D; Only non-self antigens can be immunogenic. Self antigens are normally recognized by the immune system as part of the host, so an immune response does not normally occur. Non-self antigens are immunogenic since they have the potential to cause an immune response.

For a substance to be immunogenic it must be: A. A linear molecule B. A lipid C. Less than 5,000 molecular weight D. Recognized as non-self E. A haptene

C; % concentration (expressed as a proportion or ratio) x volume needed = mass of reagent to use So... 10% (w/v) solution of sodium hydroxide x 200 mL needed = 20 grams of sodium hydroxide

How many grams of sodium hydroxide are required to prepare a 200 ml solution of a 10% (weight per volume) solution? (Atomic weights: Na = 23; 0 = 16; H = 1) A. 4g B. 10g C. 20g D. 40 g E. 80 g

C; The cells indicated by the arrows in the image are spherocytes. Spherocytes have a decreased surface to volume ratio and are therefore smaller with an increased MCHC. Spherocytes have lost their bi-concave shape and are spherical in shape, hence the name.

What are the cells that are indicated by the arrows in this peripheral blood smear image? A. Echinocytes B. Elliptocytes C. Spherocytes D. Stomatocytes

A; Alpha-fetoprotein is a substance typically used in the triple test during pregnancy and for screening chronic liver disease patients for hepatocellular carcinoma.

Increased concentrations of alpha-fetoprotein (AFP) in adults are MOST characteristically associated with: A. hepatocellular carcinoma B. alcoholic cirrhosis C. chronic active hepatitis D. multiple myeloma

1. B 2. C 3. A

Match each of the descriptions with the appropriate magnification: 1. Color, Rouleau, Overall Slide Quality, Cell Distribution 2. Platelet estimates RBC-platelet-WBC morphology WBC differential RBC inclusions 3. Select area to examine, WBC estimate A. 40X (Dry) B. 10X C. 100X (Oil)

1. A 2. A 3. B 4. A

Match each virus with its appropriate nucleic acid content. 1. Paramyxovirus 2. Rhabdovirus 3. Poxvirus 4. Orthomyxovirus A. RNA B. DNA

A = Fab fragment B = Fc fragment

Match terms with fragments resulting from papain digestion of an IgG molecule: A = Fab fragment OR Fc fragment B = Fab fragment OR Fc fragment

1. B 2. A 3. D 4. C

Match the viruses below with their associated conditions. 1. Herpesvirus 2. Papovavirus 3. Rhinovirus 4. Rotavirus A. Warts B. Herpes C. Gastroenteritis in infants D. Common Cold

B; The term affinity refers to the strength of attraction between a single antigenic determinant and a corresponding antigen binding site. The term avidity refers to the total strength of the attraction between an antibody and a multivalent antigen. The reaction between an IgM molecule (which has 10 antigen binding sites), and a multivalent antigen is therefore much stronger than that of an IgG antibody (which has only 2 antigen binding sites).

Avidity is best described by which of the following statements: A. The strength with which red cells agglutinate B. The strength with which multivalent antigens and antibodies bind C. The strength with which univalent antigens and antibodies bind D. The speed with which an antigen-antibody reaction occurs

D; The correct answer which best fits the characteristics in this question is Mycobacterium tuberculosis.

What is the MOST likely identity of an acid-fast bacilli that showed buff colored, dry, heaped colonies; niacin, nitrate, and urease positive; and took 23 days at 35ºC to grow? A. Mycobacterium avium B. Mycobacterium kansasii C. Mycobacterium bovis D. Mycobacterium tuberculosis E. Mycobacterium leprae

D; AABB Standards do not require a DAT, autologous control, or a minor crossmatch for pretransfusion testing.

Essential components of compatibility testing include all of the following except : A. Antibody screen on recipients serum B. Major crossmatch or computer crossmatch C. ABO and Rh typing of recipient D. Direct Antiglobulin Test (DAT)

A; A beam splitter is employed in a dual beam spectrophotometer.

Which of the following is not a component of a basic single beam spectrophotometer: A. Beam splitter B. Cuvette C. Prism D. Light source

B; Triglyceride blood concentrations change significantly when you eat, as opposed to relatively stable levels of cholesterol, HDL, or LDL circulating in the blood. Whenever you eat a meal that contains fat, your triglyceride levels rise, which is why it is important to have a patient fast before the sample is collected.

Which of the following lipid results would be expected to be FALSELY elevated on a serum specimen from a non-fasting patient? A. cholesterol B. triglyceride C. HDL D. LDL (not calculated)

B; Glycoprotein IIb/IIIa is integral in the process of platelet aggregation as well as clot retraction.

A defective clot retraction might be caused by which one of these? A. Lack of or defect of platelet receptor glycoprotein Ib B. Lack of or defect of platelet receptor Ilb/IIIa C. Insufficient storage of ADP in platelet granules D. Absence or defect of von Willebrand's factor

A; Some elderly individuals can have poor dietary habits which can lead to decreased nutrient absorption, including zinc.

A zinc deficiency in the elderly is often caused by: A. Decreased intake and absorption B. Decreased intake and excretion C. Increased intake and excretion D. Increased excretion and decreased absorption

A; Serum amylase and lipase levels may be slightly elevated in chronic pancreatitis, but not diagnostic enough to predict chronic pancreatitis; wheras high levels are found only during acute pancreatitis episodes. In the later stages of chronic pancreatitis, normal to decreased levels of amylase and lipase are caused by the gradual inability of the pancreas to secrete the enzyme

All of the statements below regarding amylase and lipase in pancreatitis are TRUE EXCEPT: A. Amylase and lipase are as predictive in chronic as in acute pancreatitis. B. Diagnosis sensitivity is increased by assaying both amylase and lipase. C. Urinary amylase: creatinine ratio is the most sensitive test for acute pancreatitis. D. Serum lipase peaks at 24 hours after an episode of acute pancreatitis and remains high for 7-8 days.s.

A; Acute hemolytic transfusion reactions are most commonly due to ABO-incompatible blood being transfused to a recipient with naturally occurring ABO alloantibodies (anti-A, anti-B, anti A,B).

Acute intravascular hemolysis as the result of a blood transfusion is most often associated with which of the following causes? A. Transfusion of ABO incompatible red cells B. Allergies C. Passively transfused antibodies to HLA antigens D. Transfusion-associated graft-versus-host disease

B; Autologous units must be drawn before they are needed, and must be readily available, therefore are generally not of use in emergencies.

All of the following are benefits of autologous donation except: A. Reduces exposure to infectious agents B. Are always on hand in case of an unexpected emergency C. Reduces demand for homologous blood D. Eliminates sensitization to cellular blood components

A; Though automated extraction machines have many benefits over manual methods the costs are high and generally require a high throughput of samples in order to justify the costs. Automated extraction has many benefits over the traditional manual methods. The most important benefit is that the nucleic acid isolated is constantly consistent. There is a reduced amount of manipulation with dramatically decreases the chance of cross contamination. Also, automated extraction machines are considered moderate complexity and can be performed by a wider variety of laboratory professionals.

All of the following are considered benefits of automated isolation and extraction equipment EXCEPT: A. Automated isolation equipment is cheaper and more practical B. Automated isolation equipment requires less manipulation C. Automated isolation equipment is considered moderate complexity D. Automated isolation equipment provides consistent results

C; A hapten is an incomplete antigen.

All of the following cellular antigens are important to an immunohematologist except: A. Blood group antigens B. Histocompatibility antigens C. Haptens D. Autoantigens

D; According to OSHA, Hazard Communication 1910.1200 has the purpose of ensuring that the hazards of all chemicals produced or imported are evaluated, and that information concerning their hazards is transmitted to employers and employees.

Also known as the "Right To Know Law," which one of the following OSHA regulations first dealt with specific information related to the contents of chemicals used in the workplace? A. Blood Borne Pathogens 1910.1030 B. Formaldehyde 1910.1048 C. Right To Know Communication 1910.5555 D. Hazard Communication 1910.1200 E. Occupational Exposure 1910.1450

A; Modified Thayer Martin agar at 35ºC with CO2 is the correct answer. This is a typical presentation of systemic gonorrhea and Neisseria gonorrhea grows best on MTM medium at 35ºC. under CO2. Systemic gonorrhea occurs in 1% of cases and results in purulent arthritis and rarely septicemia.

An 18-year-old woman woke up in the morning to find that her left knee was hot, swollen, and very painful. She could not walk to work and a friend offered her a ride to the clinic. She had never had a swollen joint before. Physical exam revealed a tender knee joint which yielded purulent synovial fluid on aspiration. Gram-negative intracellular diplococci were seen on Gram stain. She also had a cervical discharge that was cultured. The cause of her infection would grow best on: A. Modified Thayer Martin agar at 35ºC with CO2 B. LIM (Todd Hewitt Broth w/Colistin and Nalidixic Acid) broth with refrigerated temperature C. Blood agar at 42ºC with microaerophiilic conditions D. V (human blood) agar at 35ºC with CO2

C; 1 SD = 68.3%, 2 SD = 95.5%, 3 SD = 99.7

As defined by a Gaussian distribution curve, what percentage of values would be expected to fall within two standard deviations of the mean: A. 75% B. 85% C. 95% D. 100%

A; Atherosclerosis is a hardening of an artery specifically due to the build up of plaque. The risk to patients with significant atherosclerosis is that eventually a narrowing of the artery (stenosis) can cause a reduction in oxygen delivery to tissues and plaque rupture can lead to an acute coronary event.

Atherosclerosis is a hardening of an artery specifically due to which of the following? A. Build up of plaque B. Aggregation of platelets C. Hypercalcemia

B; Macroglobulinemia, Multiple Myeloma, and Amyloidosis are all associated with abnormal protein production and/or accumulation which can result in Bence-Jones proteins being excreted in the urine.

Bence-Jones proteinuria is associated with all of the following conditions except: The correct answer is highlighted below Macroglobulinemia Pernicious anemia Multiple myeloma Amyloidosis

D; Transpeptidase enzymes catalyze the final stage of peptidoglycan synthesis during cell wall formation. Beta-lactam antibiotics bind with these enzymes, interfering with their function. The transpeptidase enzymes are also referred to as PBP's, or penicillin-binding proteins.

Beta-lactam antibiotics interfere with cell wall synthesis by: A. Binding with a transpeptidase B. Preventing the final stage of peptidoglycan synthesis C. Interfering with PBPs D. All of the above

A & D; Rule-out is a process by which antibodies are identified as being unlikely in a given sample because of the absence of an expected antigen-antibody reaction. In other words, the absence of a reaction is noted with a cell that is positive for the corresponding antigen. Although rule-out procedures may vary somewhat from institution to institution, the following general principles apply: Non-reactive cells are selected for rule-out. To be classified as non-reactive, a cell must NOT have reacted at any phase of testing in a given panel or screen. Using the logic that if the rule-out cell is positive for a given antigen, it should have reacted with the corresponding antibody, you can rule-out antibodies that correspond to antigen positive cells. To increase the probability that rule-out will not mistakenly eliminate a weakly-reacting antibody that exhibits dosage*, use only cells that are homozygous for the corresponding antigen for those systems that generally show dosage. Generally these include: C, c, E, e, Fya, Fyb, Jka, Jkb, M, N, S, and s. In this case, it is only possible to rule out on screening cell 2 since it demonstrates a negative reaction with the patient serum. Anti-C cannot be ruled out since the C antigen is heterozygous on screening cell 2 with c. Anti-Fya cannot be ruled out since this antigen is not present on screening cell 2. Anti-M and anti-Jka can be ruled out since the antigens are homozyous while demonstrating a negative reaction on screening cell 2. Rule-out, while very useful, can lead to error. Ruling out an antibody should be combined with other supporting data to increase confidence in the solution; the more data collected, the higher the probability that the final solution is correct. *Dosage means that there are two "doses" of the same antigen present on the red cells . Antibodies that exhibit dosage react more strongly with homozygous cells (e.g., Jka Jka) than with heterozygous cells (e.g., Jka Jkb) .

Based on the phenotype of the RBC screening cells, and patient results shown on the right, which of the following antibodies CANNOT be ruled out? A. Anti-C B. Anti-Jka C. Anti-M D. Anti-Fya

D; Beer's law is based on the fact that absorbance is directly proportional to the concentration of a solution. Therefore, stray light can alter the absorbance results in this type of assay.

Deviations from Beer's Law are caused by: A. very low concentration of absorbing material B. polychromatic light C. very high concentrations of substance being measured in a colorimetric reaction D. stray light

B; Donor and recipient blood samples (samples utilized for pre-transfusion compatibility testing) must be kept for at least 7 days after transfusion. Blood samples must be available to investigate a transfusion reaction, if necessary.

Donor and recipient blood samples must be kept for at least how long after transfusion? A. 10 days B. 7 days C. 3 days D. Not a requirement

D; Bacterial contamination can manifest itself in several ways including: the presence of clots, darker purple-black color of blood unit, unit can appear cloudy, hemolysis may be present.

During routine inspection, a unit of unexpired blood was noticed to have a black color with numerous small clots. What is the likely cause for this observation? A. the unit was frozen B. donor had DIC C. viral contamination D. bacterial contamination

D; Blood collected in CPDA-1 may be stored at 1 - 6 oC for up to 35 days.

How long may blood be stored using CPDA-1 preservative prior to transfusion? A. 5 days B. 15 days C. 25 days D. 35 days

C; P. vivax characteristically displays Schuffner's dots and often enlarged RBCs along with brownish granules. P. vivax can also have 12-24 merozoies in each cell, actually filling the entire RBC. This parasite also has very irreglar shapes often referred to as "Ameboid". P. falciparum and P. malariae do not display Shuffner's dots, therefore could not be the correct choice. P. ovale does display Shuffner's dots in all stages, but characteristically has about 8-12 merozoites in rosettes or irregular clusters inside the RBC. Also, P. ovale characteristically shows enlarged, ovoid RBCs with fimbriated edges.

Identify the parasite of a patient with suspected malaria who demonstrates the following findings on a blood smear: - Enlarged RBCs, some with fine brownish granules - > 15 parasites in some cells - Ameboid structures - Schuffner's dots A. Plasmodium falciparum B. Plasmodium ovale C. Plasmodium vivax D. Plasmodium malariae

E; The indole (modified Kovacs' reagent) is used to assess the ability of certain bacteria to produce indole by the deamination of tryptophan. Indole reacts with aldehyde in the Kovac's reagent to produce a red color. An alcoholic layer holds the red color as a ring at the top of the tube used for the idole test.

If a bacteria produces the enzyme tryptophanase to break down the amino acid tryptophan, which of the following tests will be positive with Kovac's reagent? A. oxidase test B. esculin test C. catalase test D. citrate test E. indole test

C; The negative antigen frequencies are used in the formula below to determine the percent of type-specific units that would be compatible for the patient. Negative antigen frequencies are determined by subtracting the percent antigen frequency from 100%. The negative antigen frequency for K in this case is .91 (1.00 - .09) and the negative antigen frequency for Fya is .34 (1.00 - .66). % compatible units available = 100 x (Neg frequency #1 x Neg frequency #2...) For this case, the calculation is: % compatible units available = 100 x (0.91 x 0.34) = 30.94 or 31%

If the antigen frequencies for K = 0.09 and Fya = 0.66, what percent of type-specific units would be compatible for a patient with anti-K and anti-Fya? A. 10 B. 43 C. 31 D. 92 E. 100

C; On the red cell membrane, there is a bicarbonate / chloride exchanger. This exchanger allows for bicarbonate to leave the red cells while chloride is allowed inside.

In blood, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with: A. sodium B. potassium C. chloride D. phosphorus

D; An antithetical relationship exists between the antigens M and N. Antithetical relationships occur in situations where for a given locus, only one of two genes may be inherited, the alleles are termed antithetical alleles.

In immunohematology, an antithetical relationship exists between M antigen and which of these antigens? A. K B. S C. Vw D. N

B; Basophilic stippling is the term used to describe red blood cells that contain tiny particles of RNA within their cytoplasm. Basophilic stippling is associated with many conditions, but is strongly associated with lead poisoning.

Multiple small, dark blue particles scattered throughout the cytoplasm of erythrocytes is/are called: A. Pappenheimer bodies B. Basophilic stippling C. Heinz bodies D. Howell-Jolly bodies

D; Nucleated RBCs may be seen in the peripheral blood in cases of beta thalassemia major. Nucleated RBCs are usually not found in peripheral blood in cases of beta thalassemia minor and beta thalassemia intermedia, and would not be a finding in beta thalassemia minima.

Nucleated RBCs are most likely to be seen in the peripheral blood of which of these beta thalassemias? A. Beta thalassemia minima B. Beta thalassemia minor C. Beta thalassemia intermedia D. Beta thalassemia major

D; Rapid vascular constriction, not dilation, immediately occurs when there is vascular injury in order to constrict the amount of blood that escapes the vessels; ultimately preventing massive loss of blood.

Primary hemostatic processes resulting from vascular damage include all of the following EXCEPT: A. collagen activates glycoprotein IIb/IIIa during platelet activation B. von Willebrand factor mediates platelet adhesion C. platelet granule release and fibrinogen mediate platelet aggregation D. rapid and immediate vascular dilation occurs E. b & c

B; Howell-Jolly bodies are composed of DNA, usually left from the nucleus, that appears as a round, dark-staining inclusion in the cytoplasm of red blood cells. Howell-Jolly bodies can be found in various conditions including splenectomy and anemia.

Remnants of erythrocyte nuclei, nuclear fragments, or aggregates of chromosomes are called: A. Heinz bodies B. Howell-Jolly bodies C. Basophilic stippling D. Pappenheimer bodies

A, B, & E; Neutrophils, lymphocytes and macrophage/ monocytes can be found in all types of body fluid differentials. Bronchial cells can be found only in bronchial washings and BAL specimens. Mesothelial cells are found only in serous body fluids including pleural fluid, peritoneal fluid, and pericardial fluid.

Select the specific cells listed below that can be found in all types of body fluid. A. Neutrophils B. Macrophage/monocytes C. Bronchial lining cells D. Mesothelial cells E. Lymphocytes

D; Serum alkaline phosphatase is produced in the bone, intestine, and the placenta- but not in the brain.

Serum alkaline phosphatase activity is derived from all of the following organs except: A. Bone B. Intestine C. Placenta D. Brain

A; Serum calcitonin is normally produced by the C cells of the thyroid. It functions to reduce serum calcium by inhibiting release of calcium from bone. It is a peptide with a molecular weight of 3400, and has a half life of approximately 12 minutes. It is characteristically elevated in medullary carcinoma of the thyroid. Since medullary carcinoma often occurs as an autosomal disorder, family members of patients with this condition should be screened for serum calcitonin.

Serum calcitonin is typically elevated in which of the following conditions: A. Medullary carcinoma of the thyroid B. Hyperthyroidism C. Glioblastoma D. Adrenal adenoma

C; Skeletal deformations result from the increased erythropoiesis that occurs in beta thalassemia major. Children with beta thalassemia intermedia may demonstrate some facial bone deformity, however this is not common. Beta thalassemia minor rarely causes any physical signs or symptoms and beta thalassemia minima is completely asymptomatic.

Skeletal deformations are most commonly present in which of the following beta thalassemias? A. Beta thalassemia minor B. Beta thalassemia intermedia C. Beta thalassemia major D. None of the beta thalassemias E. All of the beta thalassemias equally

D; Lipids tend to form a "maltese cross" pattern when viewed in polarized light, which helps to differentiate them from other urine microscopic components.

Substances found in urinary sediment that are more easily distinguished by use of polarized microscope are: A. WBC B. RBC C. Casts D. Lipids E. Crystals

B; In Rouleaux, red blood cells appear as stacked coins - formation occurs as the result of elevated globulins or fibrinogen.

The RBCs indicated by the arrows in this illustration are the result of: A. Over drying of blood smear B. Rouleaux formation C. Cold agglutinins D. Sickle cell anemia

D; VLDL transports endogenous lipids, whereas chylomicrons transport exogenous (dietary) lipids. Cholesterol is transported by HDL and LDL.

The function of the very low density lipoproteins (VLDL) is to transport: A. cholesterol from peripheral cells to the liver B. cholesterol and phospholipids to the peripheral cells C. exogenous triglycerides D. endogenous triglycerides

B; Although any one of the answers might be considered correct, a report of gram-positive cocci in chains provides sufficient information without going beyond what the observation might allow. In off-the record conversation with the physician, a technologist might divulge that the picture is consistent with Streptococcus; however, enterococci may have a similar Gram stain appearance, potentially leading to the wrong choice of empiric antibiotic agents.

The image shows the Gram stain prepared from the positive blood culture. What is the MOST appropriate report? A. Gram-positive cocci B. Gram-positive cocci in chains C. Gram-positive cocci consistent with Streptococcus D. Gram-positive cocci consistent with Enterococcus

B; Hives and rash usually indicate an allergic reaction. Hematuria is due to a variety of causes. Fever and chills usually indicate a febrile reaction. Positive DAT due to conditions other than sensitization to red cell alloantigens is not uncommon. Therefore a positive DAT in the posttransfusion specimen with a negative DAT in the pretransfusion specimen is more likely to indicate alloimmunization.

The most definite indication that a patient has been sensitized to a specific red cell antigen is: A. Hives and rash B. A positive posttransfusion DAT in a patient with a previously negative DAT C. A positive posttransfusion DAT in a patient with a previously positive DAT D. Hemoglobinuria

This is true. There are approximately 5 hyaline casts in this image.

True or false? Hyaline casts are present in this slide.

False; A three-hour glucose tolerance test includes a fasting blood glucose after which a specified amount of glucose is ingested. Blood specimens are then collected at one, two, and three hours for a total of four blood specimens.

True/False A pregnant patient whose initial test for gestational diabetes was elevated, has orders for a three-hour glucose tolerance test. The three-hour glucose tolerance test includes two specimens: a fasting blood glucose and a specimen collected three hours after drinking a 100-gram dose of glucose solution.

True; A slide for microscopic examination of CSF should be made using a cytocentrifugation technique (cytospin). Alternate methods of slide preparation, such as concentration of cells by traditional centrifugation and manual smear methods, are not recommended as morphologies may not be maintained and sufficient cells may not be present on the slide for accurate evaluation of the sample.

True/False Cytocentrifugation is the recommended method for preparing a cerebrospinal fluid (CSF) sample for examination of cellular morphology.

True

True/False In real-time PCR procedures, fluorescence resonance energy transfer (FRET) is the process that allows for probes to emit fluorescence only after hybridization.

A & B Ferritin and hemosiderin are considered storage forms of iron.

Which substance(s) is/are considered iron storage compounds? A. hemosiderin B. ferritin C. hemoglobin D. myoglobin

True; Erysipelothrix rhusiopathiae may have colony and Gram stain features similar to that of Listeria monocytogenes. However, L. monocytogenes is motile (optimum at room temperature or 25C), hydrolyzes esculin (black), and gives a positive VP reaction (red). E. rhusiopathiae is negative for all these tests. E. rhusiopathiae produces H2S in Kligler and Triple Sugar Iron Agar while L. monocytogenes does not.

True/False Shown in the image are three tubes: (1) motility agar (note subsurface flare shown by arrows); (2) esculin hydrolysis (+), and (3) VP (+). The reactions illustrated here are sufficient to rule out Erysipelothrix rhusiopathiae.

C; A negative glucose oxidase test and a positive test for reducing sugars in urine indicates the presence of a non-glucose reducing sugar such as galactose, fructose, glyceraldehyde, etc. This is the reason that certain patient populations require additional confirmatory sugar testing on their urine samples.

A negative glucose oxidase test and a positive test for reducing sugars in urine indicates: A. True glycosuria B. A false-negative glucose oxidation reaction C. The presence of a non-glucose reducing sugar such as galactose

D; Platelet neutralization tests are one of the confirmatory tests that can be used to determine if a patient has a circulating lupus antibody, or lupus anticoagulant. The principle in this test involved the use of a freeze-thawed platelet suspension that, when mixed with the patient plasma, will neutralize the anti-phospholipid antibodies (lupus anticoagulant) present and allow for a corrected aPTT result upon re-testing.

A patient has a history of repeated spontaneous abortion. Coagulation studies reveal an elevated APTT, normal PT, normal platelet function, and normal clotting time. Schistocytes were seen on the peripheral blood smear. Which test should be performed to determine if the patient has lupus anticoagulant? A. Factor VIII assay B. mixing studies with factor-deficient plasma C. antinuclear antibody test D. platelet neutralization test

C; Diagnosis of malaria may require thick smears as well as conventional thin blood smears.

A definitive diagnosis of malaria can be made by: A. Serological testing B. Culture techniques C. Demonstration of the organisms in peripheral blood D. Biochemical reactions

B; The red portion of the NFPA diamond represents fire hazards. The fire classification system for NFPA is as follows: 0 - Will not burn 1 - Must be preheated for ignition; flashpoint above 200°F (93°C) 2 - Must be moderately heated for ignition, flashpoint above 100°F (38°C) 3 - Ignition may occur under most ambient conditions, flashpoint below 100°F (38°C) 4 - Extremely flammable and will readily disperse through air under standard conditions, flashpoint below 73°F (23°C)

A laboratory labels its secondary containers of hazardous chemicals using a color-coded system, with a different color representing each different type of hazard. The coding system follows the color-coding used by the National Fire Protection Agency's "fire diamond." What hazard would be represented by the red section on the hazard label? A. Health hazard B. Fire hazard C. Reactivity hazard D. Special hazards

B; Angiotensin is an oligopeptide in the blood that causes vasoconstriction, increased blood pressure, and release of aldosterone from the adrenals.

A major action of angiotensin II is: A. Increased pituitary secretion of petressin B. Increased vasoconstriction C. Increased parathormone secretion by the parathyroid D. Decreased adrenal secretion of aldosterone

A; Animals serve as a reservoir of infection" is the correct answer because Shigella only infects humans while Salmonella is found in many animals. Both have diarrhea as the major symptom. Endotoxin is produced by all gram negative bacteria and exotoxin is only produced by Shigella.

A major difference between Salmonella enterica and Shigella infections is that only in salmonellosis can: A. animals serve as a reservoir of infection B. diarrhea become the major symptom C. endotoxin play a role in disease process D. exotoxin produce profuse watery stools

B; The correct response is option B: The Hepatitis B "e" Antigen (HBeAg). This antigen indicates the virus is actively replicating and therefore the patient is very infectious. The hepatitis B "e" antigen is present when the virus is actively replicating. In cases of unintentional needlesticks, infectivity is of highest concern. The risk for infection is greatest during phases of increased HBeAg serology. The Hepatitis B surface antigen is the first detectable marker, but if the patient is known to have Hepatitis B already, it would be relatively unhelpful to confirm the condition with another HBsAG test. The core antigen is not detectable because it is covered by the nuclear envelope. Antibody response patterns would not be very helpful either as the patient has already been diagnosed with acute Hepatitis B. IgG antibodies would indicate recovery, which is not the case for this patient and IgM antibodies indicating a recent or acute infection would only confirm what is already known. Recall, in cases of unintentional needlesticks, infectivity is of highest concern.

A phlebotomist at a local hospital recently had an accidental needle stick while drawing blood from a patient being treated for acute hepatitis B. Which serological marker from the patient would be of most value to the physician evaluating the phlebotomist's possible infection status? A. Hepatitis B surface Antigen (HBsAg) B. Hepatitis B e Antigen (HBeAg) C. Hepatitis B core Antigen (HBcAg) D. Anti-Hepatitis B e (anti-HBe) IgM E. Anti-Hepatitis B core (anti-HBc) IgG

B; Gram-positive bacteria retain the primary crystal violet stain that is applied in the Gram stain because of the cross-linking of the thick peptidoglycan layer in their cell walls. Their cell walls contain less lipids than that of a gram-negative bacteria, and this reduces the permeability of their cell wall to the organic solvents that are used as a decolorizer. When the counterstain is added, it may enter the gram-positive cell, but does not change the color of the cells.

A thick peptidoglycan is MOST often associated with which of the following types of bacteria? A. Gram-negative bacteria B. Gram-positive bacteria C. Both gram-negative and gram-positive bacteria

C; Hb S migrates with D in alkaline and alone in acid electrophoresis.

The gel electrophoresis pattern for hemoglobin S shows which of the following migration patterns? A. Hb S migrates alone in alkaline and D in acid electrophoresis. B. Hb S migrates with D in alkaline and A in acid electrophoresis. C. Hb S migrates with D in alkaline and alone in acid electrophoresis. D. Hb S migrates with A in alkaline and D in acid electrophoresis.

False The ADA recommends regular screening for individuals who are at increased risk for diabetes. OGTT use is discouraged for these individuals unless blood glucose and HbA1C concentrations remain below diagnostic ranges for diabetes but patient displays symptoms of diabetes.

True/False The ADA recommends performing an oral glucose tolerance test (OGTT) on all individuals who are at increased risk for diabetes.

True The positive reactions for sodium citrate, urea (weak), and Voges Proskauer are negative for all strains of Escherichia coli. Most strains of E. coli are ONPG and indole positive, opposite to that seen here. Thus, a quick assessment of these reactions quickly eliminates E. coli from the differential identification.

True/False The reactions seen in the portion of the API strip shown in the photograph, effectively rules out Escherichia coli.

A; Secondary granules, also known as specific granules first appear in the myelocyte stage next to the nucleus. In neutrophils this is termed the "dawn of neutrophilia".

What is one of the main characteristics of secondary granules in the neutrophilic granulocyte cytoplasm? A. Appear first at the myelocyte stage B. Dissolve in mature granulocytes C. Are formed on the mitochondria D. Are derived from azurophil (primary) granules

C; The approximate volume of CSF in an adult is 90-150 mL.

What is the approximate volume of spinal fluid in an adult? A. 10-40 mL B. 50-70 mL C. 90-150 mL D. 200-500 mL

A; Know what you are handling - read label carefully.

What is the first thing you do before you handle or open a chemical: A. Read the label B. Ask a supervisor for assistance C. Obtain a copy of the SDS D. Consult procedure manual for information

E; Stuart Prower factor, or factor X, would cause abnormal PT, aPTT, and dRVVT test results as factor X is part of the common coagulation pathway and therefore measured in both the PT and aPTT test. In the dRVVT test, factor X is directly activated in the test principle; therefore an abnormal result would be expected in this test as well if there was a deficiency in factor X.

What tests will be abnormal in a patient with Stuart-Prower Factor deficiency? A. Prothrombin Time (PT) B. Activated Partial Thromboplastin Time (APTT) C. Russel Viper Venom Test (dRVVT) D. a & b E. a & b & c

D; In the interpretation of the Schilling's test, if stage I is abnormal with a normal stage II- this is indicative of a correction by intrinsic factor, which indicates that the patient has pernicious anemia.

What would the following Schilling test results indicate: Part I: 2% excretion of radioactive vitamin B12 (normal: 5-35%) Part II: 8% excretion of radioactive vitamin B12 after intrinsic factor was given with vitamin B12 (normal: 7-10%). The correct answer is highlighted below Tropical sprue Transcobalamin deficiency Folic acid deficiency Pernicious anemia

A; Gating sets up boundaries around a subset of data points to segregate those events for analysis. Gating the proper cell population is crucial for flow cytometric analysis. The CD marker information presented on the histogram data is only representative of the cells inside the gate.

When analyzing the raw data of a sample on the flow cytometer, CD marker information on the histograms represents data inside the _____ population. A. Gated B. Non-gated

D; Heparin is the additive of choice for blood gas syringe collection as it has the least amount of interference with the blood gas analytes measured.

Which of the following additives should be used for the collection of a sample for blood gas analysis: A. Sodium citrate B. EDTA C. Sodium oxalate D. Heparin

A; In primary responses, the major class of antibody produced is IgM whereas in the secondary response, as mentioned in this question, it is IgG. IgG is present in the highest quantities compared to all other antibody classes and is the only antibody able to cross the placental barrier.

Which of the following antibody types is chiefly seen in the secondary immune response: A. IgG B. IgA C. IgM D. IgD

B; The conidia of Exophiala species are produced within phialides that extrude the conidia in tight, ball-like clusters. The large, drum stick-shaped muriform macroconidia of Alternaria species are arranged in short chains; the small, elliptical conidia of Cladosporium species are arranged in both long and short, branching chains.

Which of the following dematiaceous fungal species produce conidia in clusters? A. Alternaria species B. Exophiala species C. Cladosporium species

C; The Westgard multi-rule 22S describes the scenario where two consecutive data points fall outside +2SD or -2SD. If this occurs, then the run must be rejected. This situation is most likely caused by a systematic error.

Which of the following describes the Westgard multi-rule 22S? A. Two control data points are within ± 2s B. One control data point falls outside +2s and a second point falls outside - 2s C. Two consecutive data points fall outside +2SD or -2SD D. Two consecutive data points fall inside +2s E. Two points are within 2SD

B; Unexplained bleeding is associated with immediate hemolytic transfusion reactions, but is not usually associated with delayed hemolytic transfusion reactions. The bleeding results from disseminated intravascular coagulation (DIC) due to ABO antibodies causing intraventricular hemorrhage (IVH).

Which of the following signs and symptoms may be associated with immediate transfusion reaction, but is NOT usually associated with delayed hemolytic transfusion reaction? A. Fever and chills B. Unexplained bleeding from surgical site C. Unexplained drop in hemoglobin D. Transient jaundice

B; Creatinine clearance tests are utilized to estimate the glomerular function of the kidney. The creatitine clearance calculation is defined as the volume of plasma that is cleared of creatinine by the kidney per unit of time and uses the following formula: creatinine clearance = Urine creatinine conc x Volume / Plamsa creatinine conc Creatinine clearance measurements have a recommended specimen requirement = 24-hour urine collection.

Which of the following tests would be useful in the assessment of glomerular filtration: A. 24 hour urine protein B. Creatinine clearance C. PSP test D. Urea clearance

D; The concentration of circulating ferritin is proportional to the size of iron stores.

Which of the following will give the best overall picture of a patient's iron stores: A. Albumin B. Transferrin C. Haptoglobin D. Ferritin

C; C. immitis is a dimorphic fungus which can be isolated from sputum specimens of infected individuals. When grown on Sabouraud's agar at 25o it grows as a mold with white aerial mycelium in about 3 to 5 days. C. immitis is known to produce arthroconidia which are "barrel-shaped" after 1 to 2 weeks of growth.

Within three days at 28 ºC a sputum specimen placed on Sabouraud's dextrose agar with chloramphenicol and cycloheximide produced moist, grayish growth, with a white aerial mycelium, the organism is MOST likely: A. Aspergillus fumigatus B. Blastomyces dermatitidis C. Coccidioides immitis D. Cryptococcus neoformans E. Histoplasma capsulatum

C; Type I hyperlipoproteinemia is a form of hyperlipoproteinemia associated with deficiencies of lipoprotein lipase. Hyperlipoproteinemia type II is the most common form and is classified into type IIa and type IIb, depending on whether there is elevation in the triglyceride level in addition to LDL cholesterol. Hyperlipoproteinemia type III is associated with high chylomicrons and IDL. Hyperlipoproteinemia type IV is assoicated with high triglycerides. It is also known as hypertriglyceridemia. Hyperlipoproteinemia type V is similar to type I, but with high VLDL in addition to chylomicrons.

An obese adult with premature arteriosclerosis is seen in the clinic. When her serum is tested no chylomicrons are present, LDL are normal and VLDL are increased. There is an increase in triglycerides and slight increase in cholesterol. Lipoprotein electrophoresis reveals a heavy pre-beta band. She has no skin rash and uric acid is increased. This patient has a hyperlipoproteinemia with the MOST likely type of: A. II B. III C. IV D. V E. VI

B & C; A test with high specificity accurately detects the absence of disease. The more specific a test is, the fewer false-positive results will occur. A test with high sensitivity accurately identifies the presence of disease. The more sensitive a test, the fewer false-negative results it produces. In the case stated in this question, the immunoassay has high specificity, so it has few false-positives and will accurately detect those individuals who do not have the disease or condition that is being tested for. However, the test has low sensitivity, so it may not identify all individuals who actually have the disease; it may produce many false-negative results.

The accuracy of an immunoassay is its ability to discriminate between results that are true positives and results that are true negatives. Two parameters of test accuracy are specificity and sensitivity. Which of these statements apply to an immunoassay with high specificity, but low sensitivity? A. Accurately identifies the presence of disease B. Accurately identifies the absence of disease C. Has few false-positives D. Has few false-negatives

C; Allergic reactions, bacterial/viral meningitis do not cause the presence of blasts to be noted in the CSF. Leukemia with CNS involvement will show immature cells, similarly to the peripheral blood smear.

The image is a stained smear of cerebrospinal fluid. The cells present in this field may indicate what condition? A. allergic reaction B. bacterial meningitis C. leukemia with CNS involvement D. viral meningitis

D; Enterococcus spp. are bile esculin positive and grow in 6.5% NaCl. If they grow on the 6 µg/mL vancomycin screen agar as this isolate does, it is vancomycin resistant. If there is no growth on the 6 µg/mL vancomycin screen agar, the isolate is susceptible to vancomycin. Streptococcus Group D, not Enterococcus will not grow in the 6.5% NaCl and should not be tested for vancomycin resistance. Staphylococcus epidermidis is catalase positive.

The images below represent a gram-positive, catalase-negative, non-motile coccus inoculated to bile esculin agar, 6.5% NaCl broth and to 6 µg/mL of vancomycin in Mueller Hinton agar. It should be reported as: A. Enterococcus spp., Susceptible to vancomycin B. Streptococcus Group D, not Enterococcus C. Staphylococcus epidermidis, Resistant to vancomycin D. Enterococcus spp., Resistant to vancomycin

False Platelets do not contain nuclei. They are fragments of megakaryocyte cytoplasm. Therefore, they are not the smallest nucleated cell found in peripheral blood.

True/False Platelets are the smallest nucleated cells seen in normal peripheral blood.

C; The identification of the crystals depicted in this image are triple phosphate crystals. Triple phosphate crystals may be normal but are usually associated with alkaline urine. These colorless crystals have a characteristic "coffin lid" appearance.

What is the identification of these crystals seen in urine with an alkaline pH? A. Uric acid B. Calcium oxalate C. Triple phosphate D. Calcium carbonate

B; The disc diffusion method for antibiotic susceptibility testing is the Kirby-Bauer method. The agar used for this procedure is Meuller-Hinton.

Which of the following media is commonly used when performing the Kirby-Bauer disk diffusion? A. Chocolate agar B. Mueller-Hinton agar C. Thayer-Martin agar D. MacConkey agar

C; Clostridium difficile is a gram-positive, spore-forming bacilli. The remaining organisms will all stain gram-negative on direct smear or smears made from culture.

Which of the following organisms are gram-positive? A. Neisseria gonorrhoeae B. Brucella species C. Clostridium difficile D. Pseudomonas aeruginosa

A; Hemolytic transfusion reactions seldom occur because the incidence of unexpected antibodies in random patients is relatively low, e.g., 3-5% is sometimes cited. Being transfused with O Rh negative RBC is irrelvant if you have an unexpected antibody like anti-K or anti-c. Incompatible red cells may "bleed out" but only if bleeding is brisk. Even then, a hemolytic reaction may occur later once the patient's antibody rebounds and destroys remaining antigen-positive donor red cells. It's true that some patients have only cold-reactive antibodies that will not react at body temperature. But this does not explain why warm-reactive red cell antibodies cause few reactions

Why do so few patients transfused with un-crossmatched red cells in an emergency experience a hemolytic transfusion reaction? Select the one best reason. A. The incidence of unexpected red cell antibodies is relatively low. B. They usually receive group O Rh negative red cells; a hemolytic transfusion reaction will never occur if O Rh-negative red cells are transfused. C. They hemorrhage so severely that incompatible donor red cells "bleed out" before a reaction occurs. D. Some patients have cold-reactive antibodies that will not react at body temperature.

B; The colonies seen growing on the bird seed agar appear smooth and have a distinct reddish-brown pigmentation. The active ingredient in bird seed (Guizotia abyssinica) agar is caffeic acid, which is extracted and placed in an agar containing 1% glucose. Of the cryptococci, and other species of yeasts, Cryptococcus neoformans selectively produces the enzyme phenoloxidase, which oxidizes the caffeic acid in the medium to melanin, producing the red-brown pigmentation. The other yeast species included in this exercise do not possess phenoloxidase activity and therefore remain non-pigmented when grown on bird seed agar.

The colonies shown in this photograph were grown on Guizotia abyssinica (bird seed) agar at 30°C for 72 hours. The most likely identification is: A. Cryptococcus laurentii B. Cryptococcus neoformans C. Candida parapsilosis D. Saccharomyces cerevisiae

C; In excess triglycerides, the triglycerides reduce the amount of cholesterol in LDL particles producing small dense LDL molecules. Because of size and density, these molecules more easily enter damaged endothelium and vessel walls and are more easily incorporated as plaque is formed.

Which statement best describes small dense LDL particles that can occur in atherogenic dyslipidemia? A. Small dense LDL molecules are less atherogenic than larger, less dense or buoyant LDL particles because they are metabolized faster B. Small dense LDL molecules transport more cholesterol and thus are more atherogenic C. Small dense LDL molecules are more atherogenic because they can more easily move into the endothelium and vessel wall

A; This is an example of a cell cycle dependent speckled ANA pattern called anti-proliferating cell nuclear antigen (PCNA). With this pattern the antigen that the antibodies are directed against is only expressed during a limited portion of the cell's growth cycle. During other parts of the growth cycle the antigen is not expressed. This creates a pattern where only 30-50% of the cells stain positive. The speckled staining within these positive cells varies between coarse speckled (a) and smooth speckled (b). Cells not expressing the antigen are negative (c).

The image represents the results of an antinuclear antibody (ANA) test that is viewed using fluorescent microscopy. The speckled staining within these positive cells varies between coarse speckled (a) and smooth speckled (b). Cells are also present that are negative (c) because these cells are not expressing the antigen that the antibodies are directed against. This image represents which of the following ANA testing patterns? A. Anti-proliferating cell nuclear antigen (anti-PCNA) B. Speckled C. Multiple nuclear dots D. No pattern; it is negative

D; Escherichia coli and Klebsiella pneumoniae are two good quality control choices for the indole test. E. coli is indole positive, while K. pneumoniae is indole negative. A positive reaction is noted when there is a red layer at the top of the tube after the addition of Kovács reagent, while the negative result is a lack of color change in the top of the tube after the addition of Kovács reagent.

Which one of the following combinations of organisms would be appropriate positive and negative controls to verify the specific test functions listed? A. Beta hemolysis - Escherichia coli and Streptococcus pyogenes B. Catalase - Staphylococcus aureus and Staphylococcus epidermidis C. Hydrogen sulfide production - proteus mirabilis and Salmonella typhi D. Indole - Escherichia coli and Klebsiella pneumonia E. Carbohydrate fermentation - Alcaligenes faecalis and Acinetobacter baumannii

B; G6PD deficiency causes an increased suseptibility to the oxidation of hemoglobin, which in turn, causes the precipitation of hemoglobin inside of the red blood cell.

Which one of the following conditions is associated with glucose-6-phosphate dehydrogenase (G6PD) deficiency? A. Microcytic red cells B. Precipitation of hemoglobin C. Faulty heme synthesis D. Hemoglobins with low oxygen affinities

A; Serum ferritin is a good indicator of iron deficiency. However, it acts like an acute phase reactant, being elevated in a large number of conditions. Patients who have iron deficiency as well as another condition that elevates serum ferritin levels may therefore have normal or even elevated serum ferritin levels.

Which one of the following statements about serum ferritin are true: A. It is a sensitive indicator of iron deficiency B. Elevation of serum ferritin is specific for hemochromatosis C. It is synonymous with transferrin D. It is a better test for bone marrow iron stores than a Prussian blue stain of marrow particles

C; Amniotic fluid bilirubin is increased in association with the severity of hemolytic diseases of the newborn. As red blood cells lyse during these conditions, bilirubin builds up as a byproduct of the red cell destruction. The more red blood cells that are being destroyed in the baby, the more increased the bilirubin level will become.

Which one of the following tests BEST correlates with the severity of hemolytic disease of the newborn (HDN). A. Rh antibody titer of baby's blood B. L/S ratio C. amniotic fluid bilirubin D. antibody titer of mother's blood

C; Alpha thalassemia is a hemolytic anemia. In most hemolytic anemias the LD and bilirubin are increased while the haptoglobin is decreased. However, because haptoglobin binds to the alpha chain portion of hemoglobin, it usually remains at normal levels due to the absence of alpha chains in the destroyed cells.

Which set of chemistry results would most likely occur during hemolytic crisis in alpha thalassemia intermedia? A. Decreased lactate dehydrogenase (LD)and bilirubin, and increased haptoglobin B. Increased LD and bilirubin,and decreased haptoglobin C. Increased LD and bilirubin, and normal haptoglobin D. Normal LD and bilirubin, and decreased haptoglobin

C; Once substance H is developed, the addition of the sugar N-acetylgalactosamine to the terminal position of the chain gives the molecule "A" antigenic activity.

Which specific terminal sugar causes a red cell to have A antigenic activity? A. Galactose plus glucose B. Galactose C. N-acetylgalactosamine D. Glucose

B; Whole blood glucose values are lower than plasma glucose values. For this reason, point-of-care whole blood glucose meters are programmed to correct the value before presenting the result; therefore, the whole blood glucose meter result correlates to serum or plasma results.

Whole blood glucose values are ____________ plasma glucose values. A. Greater than B. Lower than C. Equal to

D; Most researchers believe that the small size and increased density of LDL molecules found in atherogenic dyslipidemia enable the molecules to more easily invade the endothelium and arterial wall of vessels.

Why are small dense LDL molecules more atherogenic? A. Small dense LDL molecules contain less cholesterol and phospholipid B. Small dense LDL molecules increase the concentration of HDL-C in the blood C. Small dense LDL molecules increase the concentration of adoponectin and inflammatory cytokines D. Small dense LDL molecules have greater mobility in the endothelium and arterial wall


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