Quiz Questions

Question 1

What is the maximum recommended time from specimen collection that plasma or serum can sit unspun?

Answer 1

2 hours after collection

Question 2

Which of the following is correct regarding CSF handling and processing if only one tube of specimen is collected?

Answer 2

Microbiology will be first to handle & process this sample

Question 3

Which of the following POCT categories is subject to the lowest level of regulation?

Answer 3

Waived tests

Question 4

When using dry ice for transportation of frozen or refrigerated specimens, why should the container be vented?

Answer 4

To prevent build-up of carbon dioxide under pressure

Question 5

What is the most critical aspect of blood culture collection?

Answer 5

Skin antisepsis

Question 6

Why are EDTA specimens obtained before other specimens when collected by skin puncture?

Answer 6

To minimize effects of platelet clumping

Question 7

How does heparin prevent blood from clotting?

Answer 7

By inhibiting thrombin

Question 8

What is the change prolonged tourniquet application may cause in blood composition?

Answer 8

Hemoconcentration

Question 9

Which instance may lead you to suspect that you have accidentally punctured an artery during a venipuncture?

Answer 9

The blood pulses into the tube

Question 10

What is the maximum time that a tourniquet should be applied?

Answer 10

1 minute

Question 11

Which of the following is the greatest source of error in POCT?

Answer 11

Pre-analytical errors

Question 12

What is the purpose of reverse isolation?

Answer 12

To protect susceptible patients from outside contamination

Question 13

A missing blood sample is found in the phlebotomist’s tray 4 hours after collection. Which tests would be most affected by this delay in centrifugation?

Answer 13

Glucose, electrolytes

Question 14

Which of the following crystals may be present in a urine with a pH of 7.5?

Answer 14

Triple phosphate

Question 15

What is the most common source of false negative results for Glucose reagent strip testing on urines?

Answer 15

Improperly preserved urine

Question 16

Which pathological condition should be considered when large numbers of calcium oxalate crystals are seen in the urine?

Answer 16

Ethylene glycol ingestion (anti-freeze)

Question 17

Which of the following casts is most associated with tubular obstruction and prolonged urine stasis?

Answer 17

Waxy casts

Question 18

The protein dip stick test is based on “protein error” of an indicators. What does this mean?

Answer 18

At a specified pH the indicator will change color in the presence of protein

Question 19

Which specific gravity is most plausible in the urine of a patient with untreated diabetes insipidus?

Answer 19

1.001 - 1.005

Question 20

Urine has tested positive for blood using a reagent strip but microscopic examination shows no red blood cells. How would one account for this discrepancy?

Answer 20

Urine is contaminated with strong oxidizing agents such as soaps or detergents

Question 21

Which of these casts is most associated with glomerulonephritis?

Answer 21

RBC casts

Question 22

When processing urine specimens for analysis, which of the actions can cause falsely high counts of microscopic urine sediment?

Answer 22

Centrifuging a larger volume of urine than the procedure indicates

Question 23

Which of the following describes the clinical significance of testing urine specific gravity?

Answer 23

Detects loss of renal tubular concentrating ability

Question 24

A urine specimen from a patient with a hemolytic transfusion reaction would be expected to show which of the following?

Answer 24

Positive for urobilinogen; negative for bilirubin

Question 25

What factor enhances formation of casts in the distal and collecting tubules of the kidney?

Answer 25

Increased solute and protein excretion

Question 26

What is the Creatinine Clearance Formula?

Answer 26

CC = U(cr) x U(vol) x 1.73 S(cr) t BSA CC= urine (creatine) in L/serum CR x Urine/Time (Hrx60) x 1.73/BSA

Question 27

Which of the following situations could create a falsely high urine pH?

Answer 27

Storage of urine at room temperature for 5 hours

Question 28

In hypertonic urine, how do red blood cells predominately appear under the microscope?

Answer 28

Crenated cells

Question 29

It is important to blot excess urine off the urine dipstick after dipping. Otherwise "run-over" will occur when the acid buffer from the reagent in the protein area runs into the pH area. What effect will run-over produce?

Answer 29

False lowering of the pH reading, especially in alkaline urine

Question 30

Which of the following statements is true about glucose testing by reagent strips?

Answer 30

Glucose oxidase and peroxidase are impregnated onto the reagent strip

Question 31

Which of the following needs to be considered when a urine specific gravity result is less than 1.000?

Answer 31

This result is not plausible

Question 32

What term is used to describe white cells which expand in dilute or hypotonic urine, and may have granules that demonstrate Brownian motion?

Answer 32

Glitter Cells

Question 33

Which of the following statements is correct with regards to the calibration of pipettes?

Answer 33

Pipette calibration is performed to verify accuracy & precision of the device

Question 34

Which term best describes procedures that remove all contamination by killing microorganisms and their spores?

Answer 34

Sterilization

Question 35

Which of the following must be stable in the reagent for accurate measurements of lactate dehydrogenase?

Answer 35

NAD/NADH

Question 36

A mole of NaCl is added to a kilogram of water. Which of the following changes occurs in the colligative properties of this solution?

Answer 36

osmotic pressure is increased and freezing point is decreased

Question 37

Which of the following most affects measurement of freezing point depression?

Answer 37

Number of solutes and dissociation of those solutes

Question 38

Which of the following ketone bodies is predominantly tested in urine?

Answer 38

Acetoacetate

Question 39

Which one of the following results may indicate primary hyperthyroidism?

Answer 39

↑free T3

Question 40

Which of the following enzyme combinations is useful as an indication of obstructive jaundice?

Answer 40

GGT, alkaline phosphatase

Question 41

Which statement best characterizes Type I diabetes?

Answer 41

High glucose levels lead to ketoacidosis

Question 42

Why is the glucose oxidase method highly specific?

Answer 42

It uses enzymatic reagents

Question 43

Which of these statements is true about anti-diuretic hormone (ADH)?

Answer 43

It will be secreted if a person is dehydrated

Question 44

A patient has a glucose result of 6.1 mmol/L with an elevated hemoglobin A1C and normal CBC. What would explain these results?

Answer 44

Patient's glucose was well managed for the day of collection but long term management was poor

Question 45

Which lipid profile below is associated with coronary heart disease?

Answer 45

Decreased HDL, increased LDL and triglycerides

Question 46

Which of the following tests are most useful in the diagnosis of acute pancreatitis?

Answer 46

Lipase

Question 47

In a competitive immunoassay done to measure a drug level, which of the following is constant?

Answer 47

Labelled antigen

Question 48

What is the number of amplified pieces of DNA after five cycles of PCR?

Answer 48

32 2 to the power of cycles

Question 49

In a PCR, which of these functions are dNTP's involved in?

Answer 49

Extension

Question 50

Which statement regarding sandwich ELISA is correct?

Answer 50

Antibody is labelled with enzyme

Question 51

What is the most common method for measuring therapeutic drug levels?

Answer 51

Immunoassay

Question 52

Which of the following is correct in regards to the majority of therapeutic drug analysis?

Answer 52

Most methods will analyze the free and bound drug combined

Question 53

What is the principle of measurement by chemiluminescence immunoassay?

Answer 53

Amount of light emission caused by products of a specific chemical reaction

Question 54

Most toxic reactions of drug overdoses lead to metabolic acidosis. Which of the following creates an initial respiratory alkalosis?

Answer 54

Salicylate

Question 55

What is the most common confirmatory testing method for drugs of abuse?

Answer 55

Gas chromatography/mass spectrometry

Question 56

What effect does antigen excess have during an immunoassay?

Answer 56

Falsely low results

Question 57

What is the appropriate time for the collection of trough drug levels?

Answer 57

Just before dosage is given

Question 58

Which of the following reagents is excluded from a PCR reaction?

Answer 58

Polyethylene glycol

Question 59

What statement is correct in regards to FPIA?

Answer 59

Uses an antigen labeled with a fluorescing molecule

Question 60

In TDM pharmacokinetics, which of the following best describes steady state?

Answer 60

Condition in which drug input and drug output are equal

Question 61

A patient is exhibiting symptoms of drug toxicity but the lab results show the drug to be in therapeutic range. What is the most likely explanation to this issue?

Answer 61

The patient's disease state produced an altered drug absorption and distribution

Question 62

Which statement is true with regards to metabolism and elimination of the majority of therapeutic drugs?

Answer 62

Most drugs are metabolized by the liver and eliminated by the kidneys

Question 63

Which statement best describes immunofixation electrophoresis (IFE)?

Answer 63

Proteins are separated by electrophoresis followed by overlay of monospecific anti-immunoglobulins

Question 64

In steric exclusion chromatography, molecules are separated on the basis of size and shape. Which statement is true?

Answer 64

Column is packed with a porous material

Question 65

Which of the following gas chromatography detectors is the most sensitive and stable?

Answer 65

Flame-ionization

Question 65

Which one of the following is most likely to be increased in an acute infection?

Answer 65

IgM

Question 66

How can denaturation of serum proteins be minimized during electrophoresis?

Answer 66

Maintaining an optimal current

Question 67

Which chromatography system uses silica gel on a piece of glass and a mobile phase of liquid?

Answer 67

Thin-layer

Question 68

Unexpected results were obtained upon performing serum protein electrophoresis. Protein bands look shorter and brighter. Which of the following would account for the results obtained?

Answer 68

Wrong buffer was used; ionic strength higher than required

Question 69

Which of the following applies to reverse-phase liquid chromatography?

Answer 69

Polar mobile phase and a nonpolar stationary phase

Question 70

Serum protein electrophoresis (SPE) is normal. CSF electrophoresis shows oligoclonal banding. What clinical significance is there to these findings?

Answer 70

This is indicative of multiple sclerosis

Question 71

To be analyzed by gas chromatography, the analyte must be which of the following?

Answer 71

Volatile

Question 72

In serum protein electrophoresis (SPE), the buffer used is more acidic than the isoelectric point (pI) of the proteins. How will this affect the charge and migration of the proteins?

Answer 72

Proteins will be positively charged and move to the cathode

Question 73

Why does albumin migrate much further than gamma globulin in serum protein electrophoresis (SPE)?

Answer 73

Albumin has more negative charges

Question 74

What might be the cause of a narrow band in the β2-γ region?

Answer 74

Inadvertent use of plasma for SPE

Question 75

Urine electrophoresis shows large amounts of albumin and increased transferrin. What is the likely cause?

Answer 75

Nephrotic syndrome with glomerular proteinuria

Question 76

Using a buffer of 7.4 for serum protein electrophoresis (SPE), where will a protein with an isoelectric point of 6.0 migrate?

Answer 76

To anode

Question 77

Which one of the following is most likely to be decreased in an acute inflammatory reaction?

Answer 77

Albumin

Question 78

Which of the following is the best way to detect Bence-Jones protein in urine?

Answer 78

Immunofixation of urine

Question 79

In which condition would you expect to find high serum total protein but normal albumin?

Answer 79

Multiple myeloma

Question 80

Which of the following is true of MALDI-TOF MS analysis?

Answer 80

Mass spectrum is unique to bacterial identification, a proteomic analysis, large ions are slow

Question 81

In mass spectrometry, the degree of bending (deflection) of an ion is inversely proportional to the mass (m) and directly proportional to the charge (z). Which of these ions will bend the most?

Answer 81

Ion D with m= 10 and z =+2

Question 82

An automated chemistry instrument establishes the line of best fit for determination of concentration values of unknowns. How is this line of best fit established?

Answer 82

By using a linear regression model with calibrator results

Question 83

Which of the following best defines a reference interval (range)?

Answer 83

Interval of results expected for a defined healthy population

Question 84

In a normal distribution curve, how many values are included in two standard deviations from the mean?

Answer 84

95%

Question 85

In establishing 95% confidence limits for a method in a QC program, how many test results are expected to fall outside the allowable limits?

Answer 85

1 in 20

Question 86

What is proportional systematic error dependent on?

Answer 86

Analyte concentration

Question 87

For a spectrophotometer to work in the 380-700 nm wavelength range, what is the best light source?

Answer 87

Tungsten lamp

Question 88

Which detector is able to measure very low intensities of radiant energy and give a suitable meter response?

Answer 88

Photomultiplier cell

Question 89

Which best describes the effect of stray light on the analysis of a sample?

Answer 89

%T is falsely increased causing false decrease in absorbance

Question 90

Which of the following applies to photometric measurement of enzyme activity?

Answer 90

Enzyme concentration measurement is performed in zero-order kenetics

Question 91

The bandpass of a spectrophotometer is 10 nm. If set at 540 nm, what wavelengths will reach the sample?

Answer 91

535-545 nm

Question 92

Which of the following situations will cause an apparent increase in light absorbance?

Answer 92

Lipemic Sample

Question 93

How is a double-beam spectrophotometer different from a single-beam spectrophotometer?

Answer 93

Double beam permits automatic correction of sample and reference absorbance

Question 94

Which of the following statements regarding light measuring methods is correct?

Answer 94

Nephelometers detect light at various angles including 90°

Question 95

Which of the following best describes the principle of fluorometry?

Answer 95

Absorption and emission

Question 96

An intoxicated patient arrives to emergency room. They present with vomiting and state they had "one too many" alcoholic beverages. Which of the following is this patient most likely experiencing?

Answer 96

Metabolic acidosis & metabolic alkalosis

Question 97

Which of the following situations indicate that an instrument problem is present and requires further investigation?

Answer 97

Series of high anion gaps

Question 98

What best describes the pH at which proteins carry a zero electrical charge?

Answer 98

Isoelectric point

Question 99

A blood sample collected in a serum tube has been sitting uncapped on the bench for 20 minutes. Which of the following would have occurred?

Answer 99

Decreased ionized Ca result

Question 100

An ion specific electrode is used for the measurement of potassium. What is it prepared from?

Answer 100

Valinomycin

Question 101

Within what time frame should the blood gas specimens be analyzed?

Answer 101

30 minutes

Question 102

What does the pCO2 electrode measure?

Answer 102

Change in pH of solution surrounding the electrode

Question 103

Which method properly describes the pO2 measurement?

Answer 103

Amperometry

Question 104

Which of the following represent metabolic acidosis?

Answer 104

Decrease in HCO3⁻; decreased pH

Question 105

What is the most common cause of erroneous results in blood pH determinations, following several pH sample runs?

Answer 105

Protein build up on the electrode

Question 106

Which of the following is an essential component of quality in blood gas analysis?

Answer 106

Participating in external proficiency testing

Question 107

For accurate results, what must be done immediately prior to the testing of a blood gas specimen?

Answer 107

The sample must be mixed