Clinical Chemistry I ASCP Review | 467 Questions And Answers
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 Correct Answer - A most common light source for photometry in the
visible region. continuous spectrum (360-800 nm). near IR and UV.
Hydrogen and Deuterium (200-375 nm)
Mercury vapor- not a continuous spectrum, emitting radiation at specific wavelengths
Which of the following isolates light
within a narrow region of the spectrum?
A. Photomultiplier tube
B. Monochromator
C. Photovoltaic cell
D. Detector Correct Answer - B Use for selecting a narrow band wavelengths from a
continuous spectrum. Three kinds (prisms, filters, diffraction gratings.
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 Correct Answer - C
PMT- responds to the radiant energy light it absorbs by emitting electrons in a proportional
amount to the initial light absorbed.
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 Correct Answer - D is part of a barrier layer cell
PMT- 1. light to electricity
2. Amplification
5. 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 Correct Answer - D
256-2048 arranged in a linear fashion
Respond to a specific wavelength that results in a continuous UV/ visible spectrum.
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 Correct Answer - D
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 Correct Answer - D
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 Correct Answer - A
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 Correct Answer - C
540 +/- 5nm (10nm)
Which of the following formulas is an
expression of the Beer-Lambert law that is
routinely applied to spectrophotometric
analysis?
A. A u X C s/As = C u
B. C u X C s/As= A u
,C. A s X C s/C u = A u
D. A = 2 - log %T Correct Answer - A
1 1 . In spectrophotometry, which of the following is a mathematical expression of the
relationship between absorbance and transmittance?
A. A — abc
R A u/ C u = A s/C s
C. A = 2 - log %T
D. A = log %T Correct Answer - C
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 Correct Answer - D
Which of the following may be asso-
ciated 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 Correct Answer - C
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 Correct Answer - D
Which of the following represents
a primary advantage of performing
fluorometric over absorption spectro- scopic 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 Correct Answer - A
, 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. Correct Answer - A
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 Correct Answer - A
18. 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 Correct Answer - B
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 Correct Answer - C
uses a crystal of sodium iodide
thallium as an activator (gamma)
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 Correct Answer - C
In assaying an analyte with a single-beam atomic absorption spectrophotometer, what is the
instrument actually measuring?
A. Intensity of light emitted by the
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 Correct Answer - A most common light source for photometry in the
visible region. continuous spectrum (360-800 nm). near IR and UV.
Hydrogen and Deuterium (200-375 nm)
Mercury vapor- not a continuous spectrum, emitting radiation at specific wavelengths
Which of the following isolates light
within a narrow region of the spectrum?
A. Photomultiplier tube
B. Monochromator
C. Photovoltaic cell
D. Detector Correct Answer - B Use for selecting a narrow band wavelengths from a
continuous spectrum. Three kinds (prisms, filters, diffraction gratings.
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 Correct Answer - C
PMT- responds to the radiant energy light it absorbs by emitting electrons in a proportional
amount to the initial light absorbed.
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 Correct Answer - D is part of a barrier layer cell
PMT- 1. light to electricity
2. Amplification
5. 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 Correct Answer - D
256-2048 arranged in a linear fashion
Respond to a specific wavelength that results in a continuous UV/ visible spectrum.
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 Correct Answer - D
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 Correct Answer - D
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 Correct Answer - A
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 Correct Answer - C
540 +/- 5nm (10nm)
Which of the following formulas is an
expression of the Beer-Lambert law that is
routinely applied to spectrophotometric
analysis?
A. A u X C s/As = C u
B. C u X C s/As= A u
,C. A s X C s/C u = A u
D. A = 2 - log %T Correct Answer - A
1 1 . In spectrophotometry, which of the following is a mathematical expression of the
relationship between absorbance and transmittance?
A. A — abc
R A u/ C u = A s/C s
C. A = 2 - log %T
D. A = log %T Correct Answer - C
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 Correct Answer - D
Which of the following may be asso-
ciated 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 Correct Answer - C
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 Correct Answer - D
Which of the following represents
a primary advantage of performing
fluorometric over absorption spectro- scopic 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 Correct Answer - A
, 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. Correct Answer - A
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 Correct Answer - A
18. 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 Correct Answer - B
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 Correct Answer - C
uses a crystal of sodium iodide
thallium as an activator (gamma)
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 Correct Answer - C
In assaying an analyte with a single-beam atomic absorption spectrophotometer, what is the
instrument actually measuring?
A. Intensity of light emitted by the
