CC Flashcards

1
Q
  1. Which of the following lamps provides a continuous spectrum of radiant energy in the visible, near IR, and near UV regions of the spectrum?
    A. Tungsten-filament
    B. Hydrogen
    C. Deuterium
    D. Mercury vapor
A

A. Tungsten-filament

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2
Q
  1. Which of the following isolates light within a narrow region of the spectrum?
    A. Photomultiplier tube
    B. Monochromator
    C. Photovoltaic cell
    D. Detector
A

B. Monochromator

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3
Q
  1. Which of the following is not descriptive of a photomultiplier tube?
    A. Emits electrons proportionally to initial light absorbed
    B. Must be shielded from stray light
    C. Cannot be used with a chopper
    D. Amplifies the initial signal received
A

C. Cannot be used with a chopper

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4
Q
  1. Which of the following is false about a photomultiplier tube?
    A. Converts radiant energy (light) to electrical energy (current)
    B. Amplifies the current significantly
    C. Has a very rapid response time
    D. Is composed of an iron plate and a layer of selenium
A

D. Is composed of an iron plate and
a layer of selenium

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5
Q
  1. Which type of photodetector employs a linear arrangement that allows it to respond to a specific wavelength resulting in complete UV/visible spectrum analysis?
    A. Photomultiplier tube
    B. Phototube
    C. Barrier layer cell
    D. Photodiode array
A

D. Photodiode array

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6
Q
  1. When performing spectrophotometer quality assurance checks, what is the holmium oxide glass filter used to assess?
    A. Linearity
    B. Stray light
    C. Absorbance accuracy
    D. Wavelength accuracy
A

D. Wavelength accuracy

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7
Q
  1. In spectrophotometric analysis, what is the purpose of the reagent blank?
    A. Correct for interfering chromogens
    B. Correct for lipemia
    C. Correct for protein
    D. Correct for color contribution of the reagents
A

D. Correct for color contribution of the
reagents

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8
Q
  1. In regard to bichromatic analysis, which of the following is false?
    A. Absorbance is measured at the spectral absorbance peak for a blank and the sample using the same wavelength.
    B. Eliminates background interferences
    C. Sample concentration determined from difference in two measured absorbances
    D. Functions as a reference blank for each sample
A

A. Absorbance is measured at the spectral absorbance peak for a blank and the sample using the same wavelength.

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9
Q
  1. The bandpass of a spectrophotometer is 10 nm. If an instalment is set at 540 nm, the wavelengths that are permitted to impinge on the sample will be within what wavelength range?
    A. 530-540 nm
    B. 530-550 nm
    C. 535-545 nm
    D. 540-550 nm
A

C. 535-545 nm

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10
Q
  1. Which of the following formulas is an expression of the Beer-Lambert law that is routinely applied to spectrophotometric
    analysis?
    A. Au x Cs/As = Cu
    B. Cu x Cs/As = Au
    C. As x Cs/Cu = Au
    D. A = 2 - log %T
A

A. Au x Cs/As = Cu

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11
Q

11 . In spectrophotometry, which of the following is a mathematical expression of the relationship between absorbance and transmittance?
A. A = abc
R Au/Cu = As/Cs
C. A = 2 - log %T
D. A = log %T

A

C. A = 2 - log %T

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12
Q
  1. Which of the following is not a problem inherent in turbidimetry?
    A. Variation in particle size of samples
    B. Variation in particle size of standards
    C. Rate of aggregation or settling of particles
    D. Need to maintain a constant and specific temperature
A

D. Need to maintain a constant and specific temperature

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13
Q
  1. Which of the following may be associated with reflectance spectrophotometry as it relates to the dry reagent slide technique?
    A. Light projected to the slide at 180-degree angle
    B. Dye concentration directly proportional to reflectance
    C. Unabsorbed, reflected light detected by photodetector
    D. Reflectance values are linearly proportional to transmission values
A

C. Unabsorbed, reflected light detected by photodetector

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14
Q
  1. Fluorometers are designed so that the path of the exciting light is at a right angle to the path of the emitted light. What is the purpose of this design?
    A. Prevent loss of emitted light
    B. Prevent loss of the excitation light
    C. Focus emitted and excitation light upon the detector
    D. Prevent excitation light from reaching the detector
A

D. Prevent excitation light from reaching the detector

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15
Q
  1. Which of the following represents a primary advantage of performing fluorometric over absorption spectroscopic methods of analysis?
    A. Increased specificity and increased sensitivity
    B. Increased specificity and decreased sensitivity
    C. Purity of reagents used not as critical
    D. Ease of performing assays
A

A. Increased specificity and increased sensitivity

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16
Q
  1. Which of the following may be associated
    with fluorescence polarization?
    A. Plane-polarized light is used for
    sample excitation.
    B. Small molecular complexes show
    a greater amount of polarization.
    C. It is a heterogeneous technique
    employed in fluorophore-ligand
    immunoassays.
    D. Polarized light detected is directly
    proportional to concentration of ligand
    in sample.
A

A. Plane-polarized light is used for
sample excitation.

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17
Q
  1. Which of the following may be associated
    with bioluminescence?
    A. Light emission produced due to
    enzymatic oxidation of a substrate
    B. Less sensitive than direct fluorescent
    assays
    C. Electron excitation caused by radiant
    energy
    D. Employs a radioactive label
A

A. Light emission produced due to
enzymatic oxidation of a substrate

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18
Q
  1. Nephelometry is based on the measurement of light that is
    A. Absorbed by particles in suspension
    B. Scattered by particles in suspension
    C. Produced by fluorescence
    D. Produced by excitation of ground-state
    atoms
A

B. Scattered by particles in suspension

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19
Q
  1. Which of the following instruments is
    used in the clinical laboratory or in
    reference laboratories to detect beta and
    gamma emissions?
    A. Fluorometer
    B. Nephelometer
    C. Scintillation counter
    D. Spectrophotometer
A

C. Scintillation counter

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20
Q
  1. Which of the following best describes
    chemiluminescence?
    A. Electron excitation caused by radiant
    energy
    B. Enzymatic oxidation of a substrate
    produces light emission
    C. Chemical energy excites electrons that
    emit light upon return to ground state
    D. Employs a fluorescent label that
    produces light
A

C. Chemical energy excites electrons that
emit light upon return to ground state

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21
Q
  1. In assaying an analyte with a single-beam
    atomic absoiption spectrophotometer,
    what is the instrument actually measuring?
    A. Intensity of light emitted by the
    analyte on its return to the ground state
    B. Intensity of light that the analyte
    absorbs from the hollow-cathode lamp
    C. Intensity of light that the analyte
    absorbs from the flame
    D. Intensity of the beam from the hollowcathode lamp after it has passed through the analyte-containing flame
A

D. Intensity of the beam from the hollowcathode lamp after it has passed through the analyte-containing flame

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22
Q
  1. What is the function of the flame in atomic
    absorption spectroscopy?
    A. Absorb the energy emitted from the
    metal analyte in returning to ground
    state
    B. Supply the thermal energy needed to
    excite the metal analyte
    C. Bring the metal analyte to its ground
    state
    D. Supply the light that is absorbed by the
    metal analyte
A

C. Bring the metal analyte to its ground
state

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23
Q
  1. Most atomic absorption spectrophotometers
    incorporate a beam chopper and a tuned
    amplifier. The purpose of these components
    is to avoid errors that would be caused by
    A. Variations in flame temperature
    B. Deterioration of the hollow-cathode
    lamp
    C. Stray light from the hollow-cathode
    lamp
    D. Measurement of light emitted by the
    analyte
A

D. Measurement of light emitted by the
analyte

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24
Q
  1. In potentiometry, which of the following
    is considered the standard electrode?
    A. Hydrogen electrode
    B. Calcium electrode
    C. Potassium electrode
    D. Copper electrode
A

A. Hydrogen electrode

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25
Q
  1. In an electrolytic cell, which of the
    following is the half-cell where reduction
    takes place?
    A. Anode
    B. Cathode
    C. Combination electrode
    D. Electrode response
A

B. Cathode

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26
Q
  1. Mercury covered by a layer of mercurous
    chloride in contact with saturated
    potassium chloride solution is a description of which of the following types of
    electrodes?
    A. Sodium
    B. Calomel
    C. Calcium
    D. Silver/silver chloride
A

B. Calomel

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27
Q
  1. When a pH-sensitive glass electrode is not
    actively in use, in what type of solution
    should it be kept?
    A. Tap water
    B. Physiologic saline solution
    C. The medium recommended by the
    manufacturer
    D. A buffer solution of alkaline pH
A

C. The medium recommended by the
manufacturer

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28
Q
  1. When measuring K+ with an ion-selective
    electrode by means of a liquid ionexchange membrane, what antibiotic will
    be incorporated into the membrane?
    A. Monactin
    B. Nonactin
    C. Streptomycin
    D. Valinomycin
A

D. Valinomycin

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29
Q
  1. Which of the following is false about
    ion-selective electrode analysis of sodium?
    A. Uses a glass membrane
    B. Errors occur from protein buildup on
    the membrane.
    C. Membrane coated with valinomycin
    D. Principle based on potentiometry
A

C. Membrane coated with valinomycin

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30
Q
  1. What are the principles of operation for a
    chloride analyzer that generates silver ions
    as part of its reaction mechanism?
    A. Potentiometry and amperometry
    B. Amperometry and polarography
    C. Coulometry and potentiometry
    D. Amperometry and coulometry
A

D. Amperometry and coulometry

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31
Q
  1. When quantifying glucose using an
    amperometric glucose electrode system,
    which of the following is not a component
    of the system?
    A. Product oxidation produces a current
    B. Hydrogen peroxide formed
    C. Hexokinase reacts with glucose
    D. Platinum electrode
A

C. Hexokinase reacts with glucose

32
Q
  1. To calibrate the pH electrode in a pH/
    blood gas analyzer, it is necessary that
    A. The barometric pressure be known
    and used for adjustments
    B. Calibrating gases of known high and
    low concentrations be used
    C. The calibration be performed at room
    temperature
    D. Two buffer solutions of known pH be
    used
A

D. Two buffer solutions of known pH be
used

33
Q
  1. The measurement of CO2 in blood by means
    of a PCO2 electrode is dependent on the
    A. Passage of H+ ions through the
    membrane that separates the sample
    and the electrode
    B. Change in pH because of increased
    carbonic acid in the electrolyte
    surrounding the electrodes
    C. Movement of bicarbonate across the
    membrane that separates the sample
    and the electrode
    D. Linear relationship between PCO2 in
    the sample and measured pH
A

B. Change in pH because of increased
carbonic acid in the electrolyte
surrounding the electrodes

34
Q
  1. The measurement of oxygen in blood by
    means of a PO2 electrode involves which
    of the following?
    A. Wheatstone bridge arrangement of
    resistive elements sensitive to oxygen
    concentration
    B. Direct relationship between amount of
    oxygen in the sample and amount of
    current flowing in the measuring system
    C. Change in current resulting from
    an increase of free silver ions in solution
    D. Glass electrode sensitive to H+ ions
A

B. Direct relationship between amount of
oxygen in the sample and amount of
current flowing in the measuring system

35
Q
  1. Which of the following blood gas parameters are measured directly by the blood gas
    analyzer electrochemically as opposed to
    being calculated by the instrument?
    A. pH, HCC-3, total CO2
    B. PCO2, HCOJ, PO2
    C. pH, PCO2, PO2
    D. PO2, HCOf, total CO2
A

C. pH, PCO2, PO2

36
Q
  1. Which of the following statements is
    false about anodic stripping voltammetry
    (ASV)?
    A. Based on potentiometry
    B. Occurs in an electrochemical cell
    C. Involves preconcentration of the
    analyte by electroplating
    D. Used to measure lead
A

A. Based on potentiometry

37
Q
  1. Which of the following methods allows
    for the separation of charged particles
    based on their rates of migration in an
    electric field?
    A. Rheophoresis
    B. Electrophoresis
    C. Electroendosmosis
    D. Ion exchange
A

B. Electrophoresis

38
Q
  1. Which of the following techniques is
    based on electro-osmotic flow?
    A. Capillary electrophoresis
    B. Zone electrophoresis
    C. Iontophoresis
    D. Isoelectric focusing
A

A. Capillary electrophoresis

39
Q
  1. Which of the following is not a type of
    support media used for serum protein
    electrophoresis?
    A. Agarose gel
    B. Cellulose acetate
    C. Acrylamide
    D. Celite
A

D. Celite

40
Q
  1. In serum protein electrophoresis, when a
    buffer solution of pH 8.6 is used, which of
    the following characterizes the proteins?
    A. Exhibit net negative charge
    B. Exhibit net positive charge
    C. Exhibit charge neutrality
    D. Migrate toward the cathode
A

A. Exhibit net negative charge

41
Q
  1. Which of the following characteristics will
    a protein have at its isoelectric point?
    A. Net negative charge
    B. Net positive charge
    C. Net zero charge
    D. Mobility
A

C. Net zero charge

42
Q
  1. What dye may be used for staining protein
    bands following electrophoresis?
    A. Fat red 7B
    B. Sudan blackB
    C. Ponceau S
    D. Oil redO
A

C. Ponceau S

43
Q
  1. When electrophoresis is performed, holes
    appear in the staining pattern, giving the
    stained protein band a doughnut-like
    appearance. What is the probable cause
    of this problem?
    A. Protein denatured and will not stain
    properly
    B. Ionic strength of the buffer was too
    high
    C. Protein reached its isoelectric point
    and precipitated out
    D. Protein concentration was too high
A

D. Protein concentration was too high

44
Q
  1. What is the purpose of using ampholytes
    in isoelectric focusing?
    A. Maintain the polyacrylamide gel in
    a solid state
    B. Maintain the protein sample in
    a charged state
    C. Maintain the pH of the buffer
    solution
    D. Establish a pH gradient in the gel
A

D. Establish a pH gradient in the gel

45
Q
  1. Which of the following is not associated
    with silver stains?
    A. Reactive to nanogram concentrations
    of proteins
    B. Polypeptides stain a variety of colors
    C. Not as sensitive as Coomassie brilliant
    blue
    D. Preconcentration of CSF not
    necessary
A

C. Not as sensitive as Coomassie brilliant
blue

46
Q
  1. Which of the following is not associated
    with isoelectric focusing?
    A. Continuous pH gradient
    B. Migration of proteins with net charge
    of zero
    C. Separation dependent on isoelectric
    point
    D. Zone electrophoresis
A

B. Migration of proteins with net charge
of zero

47
Q
  1. Which of the following is an electrophoretic technique employing a pH
    gradient that separates molecules with
    similar isoelectric points?
    A. Zone electrophoresis
    B. High-resolution electrophoresis
    C. Isoelectric focusing
    D. Immunoelectrophoresis
A

C. Isoelectric focusing

48
Q
  1. Given the following information on
    a particular compound that has been
    visualized by means of thin-layer
    chromatography, calculate the /fyof
    the compound.
    Distance from origin to spot
    center = 48 mm
    Distance from spot center to solvent
    front = 93 mm
    Distance from origin to solvent
    front = 141 mm
    A. 0.29
    B. 0.34
    C. 0.52
    D. 0.66
A

B. 0.34

49
Q
  1. To achieve the best levels of sensitivity
    and specificity, to what type of detector
    system could a gas chromatograph be
    coupled?
    A. UV spectrophotometer
    B. Bichromatic spectrophotometer
    C. Mass spectrometer
    D. Fluorescence detector
A

C. Mass spectrometer

50
Q
  1. Which of the following instruments has
    a sample-introduction system, solventdelivery system, column, and detector
    as components?
    A. Atomic absorption spectrometer
    B. Mass spectrometer
    C. High-performance liquid
    chromatograph
    D. Nephelometer
A

C. High-performance liquid
chromatograph

51
Q
  1. Which type of elution technique may be
    used in high-performance liquid chromatography?
    A. Amphoteric
    B. Isoelectric
    C. Gradient
    D. Ion exchange
A

C. Gradient

52
Q
  1. Which of the following statements best
    describes discrete analysis?
    A. Each sample-reagent mixture is handled
    separately in its own reaction vessel.
    B. Samples are analyzed in a flowing
    stream of reagent.
    C. Analyzer must be dedicated to
    measurement of only one analyte.
    D. It does not have random access
    capability.
A

A. Each sample-reagent mixture is handled
separately in its own reaction vessel.

53
Q
  1. Which of the following chromatography
    systems may be described as having a
    stationary phase that is liquid absorbed on
    particles packed in a column and a liquid
    moving phase that is pumped through a
    column?
    A. Thin-layer
    B. High-performance liquid
    C. Ion-exchange
    D. Gas-liquid
A

B. High-performance liquid

54
Q
  1. Which of the following chromatography
    systems is characterized by a stationary
    phase of silica gel on a piece of glass and
    a moving phase of liquid?
    A. Thin-layer
    B. Ion-exchange
    C. Gas-liquid
    D. Partition
A

A. Thin-layer

55
Q
  1. Which of the following does not apply to
    gas-liquid chromatography?
    A. Separation depends on volatility of the
    sample.
    B. Separation depends on the sample’s
    solubility in the liquid layer of the
    stationary phase.
    C. Stationary phase is a liquid layer
    adsorbed on the column packing.
    D. Mobile phase is a liquid pumped
    through the column.
A

D. Mobile phase is a liquid pumped
through the column.

56
Q
  1. Ion-exchange chromatography separates
    solutes in a sample based on the
    A. Solubility of the solutes
    B. Sign and magnitude of the ionic charge
    C. Adsorption ability of the solutes
    D. Molecular size
A

B. Sign and magnitude of the ionic charge

57
Q
  1. Which parameter is used in mass
    spectrometry to identify a compound?
    A. Ion mass-to-charge ratio
    B. Molecular size
    C. Absorption spectrum
    D. Retention time
A

A. Ion mass-to-charge ratio

58
Q
  1. Which chromatography system is
    commonly used in conjunction with mass
    spectrometry?
    A. High-performance liquid
    B. Ion-exchange
    C. Partition
    D. Gas-liquid
A

D. Gas-liquid

59
Q
  1. Which of the following may be a
    sampling source of error for an
    automated instrument?
    A. Short sample
    B. Air bubble in bottom of sample cup
    C. Fibrin clot in sample probe
    D. All the above
A

D. All the above

60
Q
  1. Checking instrument calibration,
    temperature accuracy, and electronic
    parameters are part of
    A. Preventive maintenance
    B. Quality control
    C. Function verification
    D. Precision verification
A

C. Function verification

61
Q
  1. For which of the following laboratory
    instalments should preventive maintenance
    procedures be performed and recorded?
    A. Analytical balance
    B. Centrifuge
    C. Chemistry analyzer
    D. All the above
A

D. All the above

62
Q
  1. Which of the following is not the reason
    that preventive maintenance schedules
    are required?
    A. Keep instrument components clean
    B. Replace worn parts
    C. Extend the life of the equipment
    D. Keep personnel busy when the
    laboratory work is slow
A

D. Keep personnel busy when the
laboratory work is slow

63
Q
  1. Which globin chains compose hemoglobin Aj?
    A. Two alpha chains and two beta chains
    B. Two alpha chains and two delta chains
    C. Two alpha chains and two gamma
    chains
    D. Two beta chains and two delta chains
A

A. Two alpha chains and two beta chains

64
Q
  1. Which hemoglobin may be differentiated from other hemoglobins on the basis
    of its resistance to denature in alkaline
    solution?
    A. A,
    B. A2
    C. C
    D. F
A

D. F

65
Q
  1. Hemoglobin S is an abnormal hemoglobin
    that is characterized by a substitution of
    which amino acid?
    A. Valine for glutamic acid in position 6
    on the beta chain
    B. Valine for glutamic acid in position 6
    on the alpha chain
    C. Lysine for glutamic acid in position 6
    on the beta chain
    D. Lysine for glutamic acid in position 6
    on the alpha chain
A

A. Valine for glutamic acid in position 6
on the beta chain

66
Q
  1. When performing electrophoresis at pH
    8.6, which hemoglobin molecule migrates
    the fastest on cellulose acetate toward the
    anode?
    A. A1
    B. A2
    C. F
    D. S
A

A. A1

67
Q
  1. Because of similar electrophoretic mobilities, several hemoglobins cannot be
    differentiated on cellulose acetate medium.
    Electrophoresis of hemoglobins at pH 6.2
    on agar gel may be useful in differentiating which hemoglobins?
    A. AI from A2
    B. A! from D
    C. A, from E
    D. C from A2
A

D. C from A2

68
Q
  1. In addition to performing hemoglobin
    electrophoresis, a solubility test may be
    performed to detect the presence of what
    hemoglobin?
    A. A,
    B. C
    C. F
    D. S
A

D. S

69
Q
  1. Which of the following is not quantified
    using an immunoassay method?
    A. Vitamins
    B. Hormones
    C. Electrolytes
    D. Drugs
A

C. Electrolytes

70
Q
  1. Which of the following is a homogeneous
    immunoassay where separation of the
    bound from the free labeled species is not
    required?
    A. Radioimmunoassay
    B. Enzyme-linked immunosorbent assay
    C. Immunoradiometric assay
    D. Enzyme-multiplied immunoassay
    technique
A

D. Enzyme-multiplied immunoassay
technique

71
Q
  1. The substance to be measured reacts with
    a specific macromolecule of limited
    binding capacity. Which of the following
    assays does not employ this principle?
    A. Chemiluminescence immunoassay
    B. Enzyme-multiplied immunoassay
    technique
    C. Fluorescent polarization immunoassay
    D. High-performance liquid chromatography
A

D. High-performance liquid chromatography

72
Q
  1. Which of the following is not associated
    with the enzyme-multiplied immunoassay
    technique (EMIT)?
    A. Is a homogeneous enzyme immunoassay
    B. Determines antigen concentration
    C. Employs a labeled reactant
    D. Enzyme reacts with drug in serum
    sample
A

D. Enzyme reacts with drug in serum
sample

73
Q
  1. When using EMIT, the enzyme is coupled
    to
    A. Antibody
    B. Antigen
    C. Substrate
    D. Coenzyme
A

B. Antigen

74
Q
  1. The enzyme activity measured in the
    EMIT is the result of the reaction between
    the substrate and coenzyme with
    A. Free antibody
    B. Free unlabeled antigen
    C. Free labeled antigen
    D. Labeled antigen-antibody complexes
A

C. Free labeled antigen

75
Q
  1. Singlet oxygen reacting with a precursor
    chemiluminescent compound to form a
    decay product whose light energizes a
    fluorophore best describes
    A. Fluorescent polarization immunoassay
    B. Enzyme-multiplied immunoassay
    technique
    C. Electrochemiluminescence immunoassay
    D. Luminescent oxygen channeling
    immunoassay
A

D. Luminescent oxygen channeling
immunoassay

76
Q
  1. Which of the following stimulates the
    production of singlet oxygen at the surface
    of the sensitizer particle in a luminescent
    oxygen channeling immunoassay?
    A. Radiant energy
    B. Heat energy
    C. Enzymatic reaction
    D. Fluorescent irradiation
A

A. Radiant energy