Chem TB Flashcards Unit 2
1) If tandem mass spectrometry is combined with a
chromatographic separation, what is added to the physical
property characterization of the compound being
analyzed?
2) In what mass spectrometers does the fragmentation of ions
take place after they have been separated by their m/z
value in a first stage?
3) What is the function of the vacuum system in a mass
spectrometer?
4) In regard to mass spectrometry, what is a molecular ion?
5) How is trapping-type spectrometry different from typical
beam-type mass spectrometry?
6) You would like to offer a service to the researchers in
your institution for identification and quantitative analysis
of proteins produced by microorganisms in liquid media
using your HPLC-mass spectrometer system. Which one
of the ionization techniques is best suited for this analysis?
7) You would like to offer a service to the researchers in
your institution for identification and quantification of
organic acids produced by microorganisms using your gas
chromatograph-mass spectrometer system. Before
selecting an ionization technique, you choose to run trial
samples with electron and chemical ionization. You notice
that the m/z of the acidic ions produced by chemical
ionization is higher than the m/z produced using electron
ionization. What is the cause of this disparity?
8) In a mass spectrometer, ion detection is typically
accomplished through the use of an electron multiplier.
This involves:
9) What type of mass spectrometer uses radio frequency–
generated fields to confine ions in three dimensions?
10) An example of a clinical application of an HPLC coupled
to a tandem mass spectrometer would be:
11) In a mass spectrometer, the ion with the highest
abundance in the mass spectrum that is assigned a relative
abundance of 100% is referred to as the:
Retention time
In a tandem mass spectrometer
To keep ions from colliding
during interactions with the
magnetic or electric fields
It is the unfragmented ion of
the original molecule being
studied.
Trapping-type mass
spectrometry uses an ion trap
designed to collect ions in
three dimensions instead of
two dimensions as in a typical
beam-type mass spectrometer.
Electrospray
Organic acids are not fully fragmented
by chemical ionization, yielding a
higher mass number.
a chain of dynodes that
“multiplies” the number of
electrons to provide a
detectable signal.
Quadrupole ion trapping-mass
spectrometer
screening and confirming the
presence of inborn errors of
metabolism.
base peak.
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Chem TB Flashcards Unit 2
12) The soft ionization technique that uses a UV-absorbing
compound upon which the analyte of interest is placed and
eventually vaporized into a plume of ions directed into the
mass analyzer is:
13) Because of the ability to identify and quantify proteins in a
complex mixture, mass spectrometry combined with
separation methods is an excellent analytical tool used
specifically in the field of:
14) In regard to the expression of enzyme activity, a katal is:
.
15) When a coenzyme binds to an enzyme, the enzyme
portion of the resulting molecule is referred to as the:
16) What is a correct statement describing a property of an
enzyme?
17) Statin drugs lower cholesterol by competitive inhibition of
the cholesterol-synthesizing enzyme HMG-CoA
reductase. A competitive inhibitor binds:
18) How does pH alter an enzymatic reaction rate?
19) Regarding enzyme kinetics, the substrate concentration at
which the reaction velocity is equal to 0.5 Vmax is referred
to as:
20) Zero-order kinetics occurs during the beginning of an
enzyme-catalyzed reaction when a substrate concentration
is high and the rate of the reaction is _____ on the _____
concentration.
21) True isoenzymes, which are multiple forms of an enzyme
that possesses the ability to catalyze an enzyme’s
characteristic reaction, are formed by:
22) During embryonic and fetal development, changes in
isoenzyme distribution patterns are common. These
changes are thought to result from:
23) Regarding enzyme kinetics, the Michaelis-Menten plot of
the relationship between reaction velocity and substrate
concentration is correctly expressed as what formulae?
24) Activators increase the rates of enzyme-catalyzed
reactions. In some cases, these activators interact with the
nonenzymatic component of the reaction such as the
substrate. However, in most cases the activator:
matrix-assisted laser desorption
ionization.
proteomics.
a unit that describes the
amount of enzyme that will
catalyze a mole of substrate in
1 second.
holoenzyme.
Enzymes are protein catalysts
that decrease the activation
energy of a chemical reaction.
to the active center of the
enzyme, thereby causing the
Km to increase.
By affecting key amino acids
in the enzyme protein at the
active center and other sites
Km
independent; substrate
the existence of more than one
gene locus coding for the
structure of the enzyme
protein.
differential expression and
changes in the relative
activities of gene loci within
developing cells.
 = Vmax[S]/Km + [S]
binds to the enzyme similar to the
enzyme/substrate combination.
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Chem TB Flashcards Unit 2
25) In a continuous-monitoring assessment of an enzyme
reaction rate, what is the preferable measurement?
26) When determining the activity of an enzyme in serum as
in a bisubstrate reaction, measurement of two different
substances can be made. One measurement determines the
decrease in substrate concentration acted upon by the
enzyme and the other:.
27) In the reciprocal plot pictured below, the solid line
indicates a normal enzyme reaction with no inhibition, and
the dotted line indicates a decrease in Vmax and no change
in Km. This plot is an example of which type of inhibition?
28) The reciprocal plot pictured below indicates a decrease in
Vmax and a decrease in Km. The solid line indicates a
normal enzymatic reaction. What type of enzymatic
inhibition is this?
29) Regarding measurement of a property related to substrate
concentration such as fluorescence production, the assay
that, although more technically demanding, theoretically
provides the most accurate measurement of enzyme
activity is the:
30) An example of a posttranslational modification of an
enzyme that produces an enzyme isoform would be:
31) Immobilized enzymes are used analytically in various
electrochemical techniques. The use of an ion-selective
electrode that is coated with an enzyme that produces ions
when placed in a substrate solution is a type of:
32) Any condition, such as extreme temperature or
extremes of pH, which changes the shape of the enzyme
protein structure generally causes loss of enzymatic
activity. This is referred to as:
33) In regard to factors that govern the rate of an enzymatic
reaction, first-order reaction kinetics occur at that part of
the reaction during which the rate of the reaction is:
34) The use of several enzymatic reactions linked together to
provide a means of measuring the activity of the first
enzyme or the concentration of the initial substrate is
referred to as a(n):
35) The interaction of the amino acid side chains with the
arrangement of the alpha-helices and beta-sheets to form a
three-dimensional protein structure is called the _____
structure of the protein.
36) All enzymes are classified to one of six classes based on
the reaction they catalyze. Based on this classification,
creatine kinase is a member of what enzyme classes?
Measurement of the increasing
concentration of product
measures the increase in
the concentration of the
second product formed.
Noncompetitive
Uncompetitive
two-point kinetic method.
alteration of carbohydrate side
chains.
potentiometric measurement.
denaturation.
directly proportional to the
substrate concentration.
consecutive enzymatic
reaction.
tertiary
Transferase
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Chem TB Flashcards Unit 2
37) Varying different factors and studying their effects on an
enzymatic reaction rate in the assessment of most
favorable reaction conditions for an enzyme assay is
referred to as:
38) In this heterogeneous assay, one of the reaction
components is attached to the surface of a solid phase. An
aliquot of patient sample containing the analyte of interest
is added, a wash step occurs, and an enzyme-labeled
antibody different from the bound antibody is added
followed by the substrate. This type of assay is called:
39) The substance that is typically injected into an animal to
elicit an immune response and induce formation of an
antibody is the:
40) A homogeneous fluorescence immunoassay that involves
the speed of the rotation of molecules, which is then
related to analyte concentration in a patient sample, is
known as:
41) Which immunoassay uses a label that was susceptible to
making serum cause a false positive because of
background fluorescence?
42) What is considered a quantitative immunoassay?
43) In the majority of clinical chemistry immunoassays, the
analyte of interest in a patient’s serum is typically the:
44) Certain immunoassays require separation of bound
reactant from free-labeled reactant for determination of
analyte concentration. What immunoassays requires this
separation step?
45) In an enzyme immunoassay with an enzyme-labeled
antigen, if there is a high concentration of patient antigen,
will there be _____ enzyme available to bind substrate.
46) A substance that cannot elicit an immune response alone
but that must be conjugated to a carrier molecule to cause
antibody production is referred to as a(n):
47) An antibody that has very strong affinity to a single
antigenic epitope is referred to as a(n) _____ antibody.
48) What information does crossed immunoelectrophoresis
provide that basic immunofixation does not?
49) In an ELISA procedure, the higher the concentration of
patient analyte in the test system, the _____ the amount of
product formation.
50) The component of an immunoglobulin molecule that
determines the antigenic specificity of that antibody is the:
optimization.
enzyme-linked immunosorbent
assay (ELISA).
immunogen.
fluorescence polarization
immunoassay.
Fluorescent
Electroimmunoassay
antigen.
ELISA
more
hapten.
monoclonal
It provides better resolution of
closely related proteins.
greater
sequence at the amino terminal
end of the heavy and light
chains.
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Chem TB Flashcards Unit 2
51) An immunoassay contains an antidigoxin antibody, a
digoxin-enzyme conjugate, a substrate, and the sample
containing an unknown concentration of digoxin. These
components are used in what immunoassays?
52) What methods is not a quantitative immunoassay method?
53) In a precipitin reaction, an excess of antigen over an
antibody will lead to:
54) You wish to determine which cells contain the protein
Substance P in the skin surrounding a flesh wound. Skin
scrapings are obtained, fixed in formalin, and mounted on
slides. You have an anti-Substance P antiserum. What
immunochemical protocol would be most appropriate to
use for this experiment?
55) In a noncompetitive immunoassay reaction format:
56) In a noncompetitive immunoassay reaction format, a very
high concentration of analyte antigen in the unknown
sample might produce a falsely:
EMIT
Counter
immunoelectrophoresis (CIE)
all antibody sites bound by
antigen with no formation of
precipitate.
Immunocytochemistry
antigen from an unknown
sample is allowed to react with
a solid-phase antibody, and a
second labeled antibody is
added that reacts with bound
antigen.
decreased result because the
high concentration of antigen
binds both the capture and
labeled antibody, reducing the
number of complexes formed.
nephelometry.
57) The light-scattering immunochemical method that is
considered to have the best sensitivity and a lower
detection limit for serum proteins is:
58) The most commonly used method of reducing carryover in extensive system flushing
most automated analytical systems is to use:
between specimens and sample
probe washing.
59) Your laboratory has purchased a discrete processing
Positive liquid displacement
analyzer that is dedicated to performing only thyroid
fixed-volume
hormone analysis. Which type of pipetting system will
likely be in place in this instrument?
60) An ion-selective electrode system for electrolyte analysis
continuous flow
that uses a peristaltic pump to move liquid reagents and
samples through a system of tubing is called a _____
analyzer.
61) The most significant improvement in the quality of
reduce error and variability
laboratory test results can be attributed to the ability of
caused by manual
automation to:
manipulation.
62) In a chemiluminescent analyzer system:
the excitation event that
produces light is caused by a
chemical reaction.
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Chem TB Flashcards Unit 2
63) What component causes carryover of the analyte in a
discrete analytical system that uses disposable reaction
vessels and measuring cuvets?
64) A tray of clear sample cups sits on a laboratory bench top
for an extended period of time. What analytes might be
affected?
65) The type of automated analyzer in which the operator is
able to use in-house reagents or reagents purchased from
suppliers different from the analyzer's manufacturer is
referred to as a(n):
66) In an automated laboratory workstation with a
bidirectional laboratory information system interface, the
laboratory’s bar-coded label on an individual specimen
contains information regarding identification and the
laboratory tests requesteD. The processor reads the bar
code and the analyzer performs the analyses. Where can a
preanalytical error still occur in this automated system?
67) Using whole blood as the specimen of choice in an
automated analytical system:
68) The steps involved in the completion of an automated
analytical process are collectively referred to as:
69) The point of interaction between the instrument operator
and an automated analyzer that is dedicated to a defined
task and is monitored by integrated computers is the:
70) The 80% rule of thumb that is used by some laboratories
in guiding decisions regarding automating a complete
laboratory to achieve cost reduction means:
71) The component of a point-of-care testing (POCT) system
that detects the reaction of the analyte with a binding
molecule or some other type of recognition element is the:
72) One of the most important benefits of connectivity
between a POCT device and information systems is:
The pipetting system
Bilirubin
open analyzer system.
When a data entry person
enters incorrect laboratory test
requests
essentially eliminates specimen
preparation time.
unit operations.
workstation.
if 80% of the specimen
handling situation can be
standardized and automated,
then the investment in
automation is justified.
sensor.
facilitation of the transfer and
capture of patient POCT and
quality-related data into
permanent medical records.
73) To document that an individual has satisfactorily
assess a practical
completed training and been found competent in the use of demonstration of skill through
a point-of-care testing (POCT) device, it is important to:
performance of parallel sample
analysis.
74) The final step in the documentation of satisfactory training observation of that individual’s
of an individual in the use of a POCT device is:
performance of the entire
procedure on three different
occasions.
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Chem TB Flashcards Unit 2
75) One of the problems with performing conventional quality
control (QC) testing on a single-use disposable POCT
device is that:
76) In the design of a POCT device, the component that
coordinates all the other systems and ensures that all the
required processes for an analysis take place in the correct
order is referred to as the:
77) The Connectivity Industry Consortium (CIC) developed a:
only that single testing unit is
monitored.
control subsystem.
set of standards that ensures
POCT devices meet critical
user requirements such as
interfacing between POCT
devices and information
systems.
78) An example of in vivo POCT technology would be:
optical fluorescence.
79) To assess the presence of (not the concentration of) a
immunochromatographic
specific cardiac marker, such as myoglobin in a blood
technique that is part of a
sample, the best POCT analysis to use would be a(n):
single-use qualitative cartridge
test strip.
80) Regarding internal quality control (QC) for a bench top
at least one QC sample should
analyzer:
be run a minimum of once per
shift.
81) The isoelectric point of an amino acid or protein is defined pH at which the amino acid or
as the:
protein has no net charge.
82) C-reactive protein (CRP) is considered an acute phase
albumin.
protein (APP) because its concentration in blood is
increased quickly during inflammation. An example of a
negative APP would be:
83) The acid-base properties of amino acids are important in
at neutral pH, they have
their function. Amino acids and proteins are both referred balanced positive and negative
to as ampholytes. This means:
charges.
84) The quaternary structure of a protein is the:
association of other peptide
chains with the main protein.
85) The plasma protein that demonstrates a decreased serum
haptoglobin.
concentration during an intravascular hemolytic disorder
and is used to identify this occurrence is:
86) What proteins is the most abundant plasma protein in
Alpha-fetoprotein
early embryonic life and is also measured to assess
hepatocellular carcinoma in adults?
87) Hyperproteinemia is caused by:
dehydration.
88) An increase in Bence-Jones protein in urine typically
Immunoglobulin light chain
indicates the presence of paraproteins. What is Bencefragments
Jones protein?
89) What statements concerning albumin is not correct?
Albumin is involved in plasma
reduction and oxidation
reactions.
7
Chem TB Flashcards Unit 2
90) Known functions of proteins normally present in plasma
include all of the following except:
91) The serum protein that is analyzed to determine the
presence of emphysema is:
92) What proteins are important in the regulation of
circulating iron?
93) You operate a laboratory that receives many patient
samples from the renal clinic next door. These patients
have serious kidney problems, with causes that range from
diabetes and IgA nephropathy to Fanconi syndrome.
Would you expect to see elevated or decreased total urine
protein from the patients that go to this clinic?
94) Albumin concentration in blood can be analyzed in an
empty blood collection tube containing no anticoagulant.
This means that you are analyzing
95) Serum proteins or protein complexes that precipitate at
temperatures lower than normal core body temperature
and that, if precipitated in tissues, result in vasculitis and
ischemic injury to peripheral tissues are referred to as:
96) At a physiological pH of 7.4, most amino acids:
97) At a pH of 4.0, the:
98) The element of protein structure that involves the folding
of the polypeptide in three dimensions and the formation
of disulfide bonds between cysteines is the _____
structure.
99) Refractometry is a rapid, semiquantitative method of total
protein determination. What will lead to a faulty
interpretation of protein values obtained by refractometry?
100) Immunofixation electrophoresis:
101) A malignant neoplasm that is composed of plasma cells
that exhibit monoclonality and are diffusely present in the
bone marrow is referred to as:
102) The addition of sulfosalicylic acid for a qualitative
turbidimetric protein determination of a urine specimen is
done to:
emulsification of fat.
alpha1-antitrypsin.
Transferrin
Elevated
serum that has been obtained
when no anticoagulants are
mixed with whole blood and
then centrifuged.
cryoglobulins.
have no net charge.
carboxyl and amino groups of
an amino acid become
protonated, causing the amino
acid to have a net positive
charge.
tertiary
Serum protein less that 3.5
g/dL
involves exposure of
electrophoresed proteins to
antisera against different
immunoglobulin heavy and
light chains with resultant
precipitation.
multiple myeloma.
precipitate a protein in the
specimen that might be missed
by albumin urine dipstick
methods.
8
Chem TB Flashcards Unit 2
103) Analyses of free light chains, particularly
immunoassays that measure the ratio of free - to free light chains, are sensitive indicators of:
104) The reference method for protein determination that
converts nitrogen to ammonium ions by acid digestion is
the:
105) The proteins that are deposited in tissues as aggregates
and that form -sheet structures with eventual damage to
the tissues are referred to as:
106) A healthy 27-year-old pregnant woman in the second
trimester sees her obstetrician for a routine visit. Blood
and urine samples are obtained. Total serum protein and
protein electrophoresis are performed on the blood sample
and total urine protein is also analyzed. The results of the
serum protein electrophoresis indicate a substantial
increase in the -globulin region of the
electrophoretogram. Which of the -globulins might this
be and why?
107) A tumor of plasmacytoid cells that is diagnosed as
Waldenström macroglobulinemia produces a paraprotein
that is an:
108) The most abundant complement protein component that
is common to all three pathways of complement is:
109) What is the globulin concentration of a specimen given
the following information: total protein, 6.5 g/dL, and
albumin, 3.8 g/dL?
110) A hydrolase enzyme important during digestion that
catalyzes the hydrolysis of starches while food is still in
the mouth is:
111) What transferase enzyme is involved in the conversion
of the stored form of energy to usable energy (adenosine
triphosphate [ATP]) within cardiac myocytes?
112) Increased enzyme activity is typically observed in
serum or plasma:
113) At present, the major diagnostic usefulness of tartrateresistant acid phosphatase type 5b is in its use as a marker
of conditions with:
114) What statements concerning lipase is incorrect?
115) The principal source of serum cholinesterase (CHE) in
blood is:
116) What enzymes catalyzes the transfer of an amino group
to alpha- ketoglutarate with the formation of oxaloacetate
and glutamate?
disorders of immunoglobulin
synthesis such as multiple
myeloma.
Kjeldahl method.
amyloid.
It is likely alpha1-fetoprotein
due to fetal development.
IgM.
C3.
2.7 g/dL
S-type amylase.
Creatine kinase
following injury or damage to
tissue.
an osteolytic component.
Lipase is a small enzyme that
can be detected in urine.
liver.
Aspartate aminotransferase
(AST)
9
Chem TB Flashcards Unit 2
117) If you were asked by your laboratory director to set up
an enzyme profile (group of tests) specifically to assess
hepatobiliary (biliary obstruction) disease, what sets of
enzymes would be most appropriate?
118) A physician orders several laboratory tests on a 55year-old male patient who is complaining of generalized
(all-over) pain, stiffness, fatigue, and headaches. What is
the most likely diagnosis: based on the following serum
test results: ALP—significantly increased, GGT normal?
119) Which is the most sensitive enzyme for monitoring
chronic alcoholic liver disease?
120) Activators that are required for normal CK activity
include:
121) What products are formed from the forward reaction
catalyzed by ALT?
122) All of the statements below about the clinically
significant phosphatases are true except they:
123) A 10-year-old girl visits her pediatrician with the
complaint of bone pain. Following enzyme studies, these
results were obtained: ALP 3.5 higher than upper
reference limit; NTP normal. These results are consistent
with a diagnosis of:
124) A 37-year-old woman who thinks she might be
pregnant visits her physician with a complaint of upper
right quadrant pain. Blood samples are obtained. Increased
enzyme activity was seen for ALP, AST, lactate
dehydrogenase (LD), and GGT. The ALP was 10 times
higher than the upper reference limit. A hepatitis panel
and a pregnancy test had negative results. Gel
electrophoresis was done to separate ALP isoenzymes,
with a dense liver band and what appeared to be a diffuse
placental band. If this woman’s physician has ruled out
pregnancy, activity of what other serum enzyme could be
measured to differentiate between hepatobiliary disease
and liver disease?
125) A 37-year-old woman who thinks she might be
pregnant visits her physician with a complaint of upper
right quadrant pain. Blood samples are obtained. Increased
enzyme activity was seen for ALP, AST, LD, and GGT.
The ALP was 10 times higher than the upper reference
limit. A hepatitis panel and a pregnancy test had negative
results. Gel electrophoresis was done to separate ALP
isoenzymes, with a dense liver band and what appeared to
be a diffuse placental band. If there is not a pregnancy,
what is the name given to the isoenzyme band that
migrates in the same region as the placental isoenzyme?
NTP, ALP, and glutamyltransferase (GGT)
Bone disease
GGT
magnesium only.
Pyruvate and glutamate
catalyze the transfer of amine
groups to ketoacids.
normal bone growth.
NTP
Regan isoenzyme
10
Chem TB Flashcards Unit 2
126) Tartrate-resistant acid phosphatase (TR-ACP) that is
present in unhemolyzed serum is synthesized mainly in:
127) Heart tissue contains what CK isoenzymes?
128) Why is heparin the only acceptable anticoagulant to use
when obtaining blood samples for ALP analysis?
osteoclasts.
MM and MB
Other anticoagulants contain
inhibitors of magnesium,
which is a required cofactor for
ALP activation.
There will be no effect,
because this is an acceptable
specimen for this test.
129) A specimen is received in a green top tube (heparin)
with a request for alkaline phosphatase analysis. The
plasma is separated and the test is performed. How will
this specimen type affect the ALP results?
130) What statements concerning lipase (LPS) is incorrect? A
a. When comparing LPS with amylase in diagnosis of acute
pancreatitis, amylase is a more specific diagnostic finding.
b. Following an acute attack of pancreatitis, lipase levels
elevate within 4 to 8 hours.
c. Lipase is a hydrolase that breaks down glycerol esters of
long chain free fatty acids.
d. Most serum lipase activity is derived from pancreas, but
gastrointestinal mucosa contributes a small amount.
131) What statements is incorrect concerning creatine kinase CK catalyzes the conversion of
(CK)?
creatine and ADP to creatine
phosphate and ATP.
132) The recommended assay, because of its specificity and monoclonal sandwich
sensitivity for the measurement of the activity of the CKimmunoassay.
MB isoenzyme, is the:
133) The usefulness of analyzing lipoprotein-associated
upregulation in atherosclerotic
phospholipase A2 for the identification of individuals at
lesions, particularly complex
risk for future cardiovascular events is because of its:
plaque.
134) Because your immunoassay analyzer is down for
a nonspecific result due to
maintenance, you have performed an immunoinhibition
possible presence of CK-B
assay to determine the relative presence of CK isoenzymes subunits.
in an individual who has presented with acute upper body
pain. The assay reveals a strong activity after inhibition of
CK-M subunits using a monoclonal antibody. This result
indicates:
135) Certain muscle relaxants are hydrolyzed by CHE
Decreased drug metabolism
during surgical procedures. If an individual with the
over time with resultant
a
atypical (E ) gene variant is exposed to this relaxant, what paralysis of respiratory
would occur?
muscles
136) A severely hemolyzed serum specimen from an
LD increased, CK increased
individual with hemolytic anemia is received in the
laboratory with a request for total CK and LD enzymes.
How will the results of these analyses be falsely affected
by the condition of the specimen?
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Chem TB Flashcards Unit 2
137) A phosphotransferase enzyme that has increased
activity when injury, inflammation, or necrosis of skeletal
muscle occurs is:
138) What is considered to be a nonspecific tumorassociated marker?
139) An example of a blood group antigen that would be
elevated in pancreatic cancer and is US Food and Drug
Administration (FDA) approved as an aid in monitoring
pancreatic cancer patients is:
140) Upon receipt of a test request for assay of human
chorionic gonadotropin (hCG) on a 60-year-old male, you
would:
141) The primary clinical usefulness of assessing alphafetoprotein (AFP) as a tumor marker is for:
142) Proteins found in normal fetal tissue and also in certain
tumors are referred to as:
143) The properties of an ideal tumor marker include all of
the following, except it should:
144) Follicular lymphoma occurs when the:
145) A physical agent, such as exposure to ultraviolet light
for an extended period of time, or a biological agent, such
as a virus, may cause cancer. These agents are referred to
as:
146) Proto-oncogenes are present in the human genome to
serve the function of:
147) What tumor markers is not a carbohydrate-related
tumor marker with its most important clinical use in the
assessment of breast cancer recurrence?
148) Tumor markers that are antigens located on the surface
of tumor cells are called:
149) What tumor markers is useful for monitoring germ cell
tumors or placental tumors?
150) A 35-year-old man has blood work done to assess his
hypertension and weight gain. He has also felt fatigued
and moody with some respiratory difficulties. His physical
appearance indicates possible Cushing’s syndrome and his
physician obtains blood for lab analysis. The man’s
adrenocorticotropic hormone (ACTH) level is extremely
elevated (>300 ng/L), but upon ultrasound analysis the
adrenal gland appears normal. What might be the cause of
the elevated ACTH?
CK.
Alkaline phosphatase (ALP)
CA 19-9.
perform the test because hCG
can be elevated in testicular
germ cell tumors.
monitoring therapy in patients
with liver cancer.
oncofetal antigens.
be able to distinguish between
benign and malignant tumors.
bcl-2 gene on chromosome 18
is translocated to the
immunoglobulin heavy chain
locus on chromosome 14.
carcinogens.
regulators of cell growth and
proliferation.
CA 125
carbohydrate-related tumor
markers.
hCG
Ectopic synthesis of ACTH by
small cell lung carcinoma
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Chem TB Flashcards Unit 2
151) An individual with a history of miscarriage visits her
physician to discuss her positive hCG test done with a
qualitative point-of-care device. The patient says she
"feels pregnant" but wants to be certain. Following an
ultrasound analysis, she is diagnosed with a germ cell
tumor of unknown type. What two tumor markers are
useful in classifying germ cell tumors?
152) An oncofetal antigen commonly used to assess
recurrence of tumor growth following removal of a colon
tumor would be:
153) Activated forms of normal cellular genes are termed:
154) The loss of a gene that codes for a tumor suppressor
protein would predispose certain cells to cancerous
transformation and unchecked proliferation. This class of
genetic alteration is referred to as:
155) A 49-year-old man visits his physician with complaints
of back pain; urinary frequency, especially at night; and
difficulty passing urine. Results of prostate-specific
antigen analysis reveal a value of 2.0 µg/L. The physician
diagnoses the problem as benign prostatic hyperplasia
(BPH); however, because the man’s father had prostate
cancer, the physician wants to track this patient for
possible prostate cancer development. Each year, the
man’s PSA value increases 0.5 µg/L. This increase
indicates:
156) A translocation between chromosomes 9 and 22
produces the BCR-ABL fusion gene. This is the
transforming event in 90% of individuals with chronic
myelogenous leukemia (CML). What statements regarding
the protein product of this fusion gene is correct?
157) A 25-year-old married woman has developed unusual
abdominal pain. Her mother died of ovarian cancer and
she is concerned that she is developing the same disease.
Her physician orders CA 125 and hCG analyses, both of
which return with a moderately elevated value. How
should the physician interpret these results?
158) One of the mutations that is found most frequently in
cancers and can ultimately lead to colon cancer involves a:
159) Regarding predictive value models of a tumor marker
analysis assay, receiver operating characteristic curves are
most useful in assessing tumor marker analyses because:
160) Most oncogenes are activated through:
AFP and hCG
CEA.
oncogenes.
deletion.
a normal increase in PSA over
time with age and likely BPH.
It is a cytoplasmic tyrosine
kinase that activates a number
of signaling pathways leading
to growth and inhibition of
apoptosis.
The physician should perform
more laboratory testing and
transvaginal ultrasonography to
determine whether the patient
has ovarian cancer or is just
pregnant.
point mutation in the K-ras
proto-oncogene.
they can display performance
of tests or markers over the
entire range of decision levels.
dominant mutations.
13
Chem TB Flashcards Unit 2
161) A 65-year-old man has been diagnosed with prostate
cancer and is being prepared for radiation therapy. His
physician is concerned that the cancer may have
metastasized to the patient’s skeletal system. What
laboratory analytes would give this information to the
physician?
162) What statements regarding creatinine is correct?
163) Urea:
164) Creatinine clearance is used to assess the _____ of a
patient.
165) What is the primary reagent used in the Jaffe reaction
for creatinine?
166) A practicing physician at a university student
healthcare facility often recommends to student patients
that they take large doses of vitamin C (ascorbic acid) to
fend off colds during the semester. As director of the
chemistry laboratory that serves this facility, you notice a
trend in that many of this physician’s students’ serum
creatinine levels are unusually high. You are currently
using a type of analysis based on the Jaffe reaction. What
might be the cause of the elevated values?
167) Plasma urea concentration:
168) In the measurement of urea, urea is initially hydrolyzed
by urease to form ammonium ions. BThis assay combined
with the spectrophotometric measurement of the resulting
ammonia is referred to as the:
169) Urea is produced from:
170) The major nonprotein nitrogen degradation product of
endogenous purines is:
171) Why do values obtained with the Jaffe reactions for
creatinine measurement overestimate creatinine
concentration by ~20%?
172) Why does persistently acidic urine lead to formation of
uric acid renal stones?
173) All of the following conditions are associated with
hyperuricemia except:
ALP
Most intraindividual variation
in serum creatinine is due to
muscle mass.
concentration in plasma is
increased by a high-protein diet
glomerular filtration rate
Alkaline picric acid
Elevated ascorbic acid in
serum produces a Jaffe-like
chromogen in this analysis that
can be interpreted as increased
serum creatinine.
can increase because of
decreased renal perfusion.
Berthelot reaction.
catabolism of proteins and
amino acids.
uric acid.
Noncreatinine chromogens in
the reaction that react with the
picrate in the end-point Jaffe
methods overestimate true
plasma creatinine
concentration.
Uric acid has a pKa of 5.57,
which makes it insoluble in
acidic solutions.
severe hepatocellular disease.
14
Chem TB Flashcards Unit 2
174) Creatininase reactions for creatinine assessment:
175) Uricase is used in the assay of uric acid to:
176) Primary gout is distinguished from secondary gout by:
177) A hemolyzed serum sample from an individual is
assayed for creatinine and a result is obtained that is
decreased compared to the normal reference interval. If
this individual has a normal glomerular filtration rate,
what statements is true?
178) An individual’s laboratory results indicate increased
serum creatinine and urea values, and his physician’s
diagnosis indicates a postrenal obstruction. What would
the glomerular filtration rate in this individual likely be?
179) Conversion of glucose into lactate or pyruvate is
referred to as:
180) An example of a monosaccharide would be:
181) The breakdown of glycogen stores in the liver to
increase serum glucose is referred to as:
182) Blood is collected in a tube containing no anticoagulant
and is transported uncentrifuged to the laboratory from an
outpatient clinic. Transport time at room temperature,
accessioning, and sample preparation time equal
approximately
hours. If a serum glucose level is
requested for this tube of blood, how might the results be
affected by the timing?
183) By what mechanism does glucagon promote
hyperglycemia?
184) What is the classic test to determine a diagnosis of
hypoglycemia?
185) A 75-year-old man was brought by his daughter to a
hospital emergency department. He was in a confused
state, trembling, sweating, with a rapid pulse,
lightheadedness, and complaining of hunger and epigastric
discomfort. His daughter claims that he does not drink
alcohol and that he takes oral hypoglycemic drugs to
control his diabetes. What is the likely cause of his
symptoms?
186) In an individual with a normal hematocrit, whole-blood
glucose values are approximately what percent different
from plasma glucose values?
187) The glucose assay on an analyzer uses hexokinase as
the enzyme that phosphorylates glucose. What are the
initial products formed from the first step of this reaction?
catalyze the conversion of
creatinine to creatine.
oxidize uric acid to form
allantoin.
its polygenic basis.
The assay must be subject to
interference from bilirubin.
Decreased
glycolysis.
glucose.
glycogenolysis.
The glucose value would be
increased by approximately
15%.
Glucagon stimulates glucose
synthesis by gluconeogenesis.
A 72-hour fast
He has possibly taken too
much of his medication and is
suffering from hypoglycemia.
10% lower
Glucose-6-phosphate and
adenosine diphosphate (ADP)
15
Chem TB Flashcards Unit 2
188) What coupled-enzyme glucose methods requires
extended incubation time to allow for the spontaneous
conversion of the -form of glucose to the -form so that
both forms can react with the initial enzyme in the
reaction?
189) The major storage carbohydrate in animals is _____,
which is located most abundantly in _____.
190) What has as one of its biological functions the
regulation of the lifespan of proteins?
191) A type 1 diabetic who is in the early stages of the
disease is taken to the emergency room with symptoms of
hypoglycemia. LACK of what endogenous hormones
might be the cause of this?
192) A heparinized blood sample is received in the
chemistry laboratory. After centrifugation, the plasma
appears markedly hemolyzed. If the hexokinase method is
used in this lab to measure glucose, why should this
specimen be re-collected?
193) What effect does ethanol have on blood glucose value?
194) What effect does salicylate have on blood glucose
value?
195) What effect does septicemia have on blood glucose
value?
196) What effect does epinephrine have on blood glucose
value?
197) What effect does glucagon have on blood glucose
value?
198) A 46-year-old man visits his physician complaining of
fatigue and chest pains. His family history reveals that his
father and grandfather both died of heart attacks at the age
of 50. Laboratory results indicated elevated total
cholesterol, elevated low-density lipoprotein (LDL), and
normal triglyceride. He is eventually diagnosed with
familial hypercholesterolemia and atherosclerosis. What is
the likely cause?
199) The lipoprotein with the smallest diameter and that has
a 50:50 lipid:lipoprotein ratio is the:
200) In the small intestine, _____ is (are) solubilized by
emulsification to form micelles.
201) Cholesterol is esterified to form a cholesteryl ester by
acylcholesterol acyltransferase in the cell. In the
circulation, cholesteryl esters are formed by the action of
what enzymes?
202) Recognized abnormalities of fatty acid catabolism
associated with uncontrolled diabetes mellitus include the
development of ketones. This ketosis is caused by:
Glucose oxidase method
glycogen; the liver
Glycoproteins
Glucagon
Red blood cells contain
phosphate esters and enzymes
that interfere with the
hexokinase assay.
Decreases
Decreases
Decreases
Increases
Increases
Genetic lack of LDL receptors
on cell surfaces
HDL.
cholesterol
Lecithin cholesterol
acyltransferase
excess acetyl-CoA being
diverted to form ketone bodies.
16
Chem TB Flashcards Unit 2
203) Why would high sensitivity C-reactive protein (CRP)
be an indicator of potential coronary heart disease (CHD)?
204) A 6-year-old girl has complained about painful
urination and is taken to her pediatrician. There is no
family history of CHD or any lipid abnormalities. After a
fasting blood specimen and urine specimen are obtained,
laboratory findings are as follows (healthy reference
intervals are in parentheses): serum albumin 1.8 g/dL (3.5
to 5.5 g/dL), total serum cholesterol 200 mg/dL (<170
mg/dL), LDL cholesterol 130 mg/dL (<110 mg/dL),
serum triglyceride 250 mg/dL (<200 mg/dL), serum urea
nitrogen 20 mg/dL (7 to 18 mg/dL), heavy urine protein
(normal is negative), and 1+ urine blood (normal is
negative). All other laboratory values were normal. These
findings are most compatible with:
205) What distinguishes lipoprotein(a), or Lp(a), from LDL?
206) An individual visits a physician, who notes that the
patient has splenomegaly, enlarged and orange-colored
tonsils, and tingling feelings in the extremities, indicating
peripheral neuropathy. Upon examination of the blood
smear for a white blood cell differential, many foamyappearing cells were noted. Normal triglyceride and total
cholesterol values were noted; however, a marked
decrease of HDL was also noted. What is the name of this
disorder?
207) An individual visits his physician with splenomegaly,
enlarged and orange-colored tonsils, and tingling feelings
in the extremities, indicating peripheral neuropathy. Upon
examination of the blood smear for a white blood cell
differential, many foamy-appearing cells were noted.
Normal triglyceride and total cholesterol values were
noted; however, a marked decrease of HDL was also
noted. What is the cause of this disorder?
208) The lipoprotein that, because it is considered
proatherogenic, is often measured by the laboratory to
assess the likelihood of CHD in an individual with normal
lipid values but a strong family history of cardiovascular
disease is:
It is an acute phase reactant
plasma protein that rises in
response to inflammation,
which is associated with risk of
future CHD.
a renal disorder with secondary
hyperlipidemia.
Lp(a) contains a carbohydraterich protein called apo(a) that
is covalently bound to apo B100 through a disulfide
linkage.
Tangier disease
Mutations in the ABCA1
transporter gene
lipoprotein(a).
17
Chem TB Flashcards Unit 2
209) The apolipoprotein that functions to facilitate uptake of
chylomicron remnants by the liver, is involved in
dysbetalipoproteinemia, and that has an isoform
associated with the risk of Alzheimer disease development
is apo:
210) There is an inverse relationship between what
cholesterol-containing lipoproteins and increased risk of
CHD?
211) In the 3-step assay for determination of cholesterol
concentration, cholesteryl esters must be cleaved by an
enzyme. This hydrolytic cleavage forms:
212) In the 3-st In the 3-step assay for determination of
cholesterol concentration, cholesteryl esters must be
cleaved by what enzymes for the initial step to occur?
213) The difference between traditional HDL cholesterol
assays and the direct homogeneous assay is that:
214) Cholesterol plays a role in all of the following except:
215) The polar amphipathic lipid that forms a surface
coating around a core of cholesterol esters and triglyceride
in a lipoprotein is:
216) The class of lipid that is derived from fatty acids and
that alters blood pressure by its action on arterial smooth
muscle cells is:
217) Essential fatty acids are:
218) What is (are) the principal apo B-100 containing
lipoprotein(s) secreted by the liver?
219) A 9-year-old boy was referred by his dermatologist for
a lipid evaluation after the boy developed what appeared
to be a raised yellowish rash over his palms and elbows.
The boy had no previous history of heart problems and no
family history of any coronary disorders. However, when
he was 8, he did have two acute attacks of pancreatitis and
abdominal pain. His lipid workup is as follows (specimen
was a fasting blood draw): triglyceride 3200 mg/dL
(normal <200 mg/dL), total cholesterol 190 mg/dL
(normal <200 mg/dL), glucose 160 mg/dL (normal 60 to
110 mg/dL). His HDL concentration was in normal range,
but LDL was elevated. Specimen was grossly lipemic.
What is the likely cause of these symptoms?
220) What lipid metabolic pathway involves the removal of
excess cellular cholesterol from cells and returning it to
the liver for excretion?
E
HDL
cholesterol and fatty acids.
Cholesteryl ester hydrolase
there is no physical separation
of HDL from the non-HDL
fractions and HDL is
selectively measured.
myelinization of the central
nervous system.
phospholipid.
prostaglandins.
fatty acids that cannot be
synthesized
VLDL
Lipoprotein lipase deficiency
Reverse-cholesterol transport
18
Chem TB Flashcards Unit 2
221) You have received two blood samples, one in a sodium
citrate tube for coagulation studies and the other in an
oxalate tube for glucose analysis from a patient diagnosed
with diabetes mellitus. This patient’s physician contacts
you to request that lipid and lipoprotein analyses be added
to the previous studies. What would be the best blood
specimen for lipoprotein analyses and why?
222) In addition to unesterified cholesterol, what is the
second constituent of the outer coating of a lipoprotein,
labeled with a question mark and represented by a white
circle in this diagram?
223) The Friedewald formula is used to indirectly determine
the concentration of what?
224) Approximately one-third of the daily production of
circulating cholesterol is converted in the liver to form:
225) The high-sensitivity detection method for CRP (hsCRP) used to detect low concentrations of this protein is
typically a(n):
226) The major component of a lipoprotein that functions to
maintain the structural integrity of the lipoprotein complex
and that modulates the activity of the enzymes that act on
lipoproteins is the:
227) In the intracellular-cholesterol transport pathway of
lipoprotein metabolism, cholesterol homeostasis is
maintained through control of cellular uptake. The LDL
cell surface receptor delivers lipoprotein particles
containing cholesteryl esters to lysosomes. The
apolipoprotein that is recognized by this receptor is apo:
State the metabolic disorder for the below plasma protein
abnormality.
228) Elevated serum C-reactive protein
229) Elevated retinol-binding protein
230) Decreased serum ceruloplasmin
231) Decreased haptoglobin
Serum would be best because it
has no osmotic effects on cells
and current cut points are
based on serum values.
Phospholipid
LDL cholesterol
bile acids.
light-scattering technique.
apolipoprotein.
B-100.
228.
229.
230.
231.
Inflammation
Chronic renal disease
Wilson disease
Intravascular hemolysis
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Chem TB Flashcards Unit 2
232) State the classification of the below enzymes.
a. Creatine kinase
b. Lactate dehydrogenase
c. Alkaline phosphatase
233) Match the enzyme with its correct substance required for
enzyme reaction.
a.
Creatine kinase
b.
Aspartate aminotransferase
c.
Amylase
234) True/ False
In an enzyme immunoassay such as ELISA, the specificity of
the labeled enzyme is the most important aspect of the
measurement.
235) True/ False
If programmed appropriately, a multiple-channel analyzer
could assess samples as a single-channel analyzer.
236) True/ False
Specimen bar coding has allowed for the ability of a system
operator to place specimens in random sequence, thereby
eliminating the need for specimen load lists.
A Transferase
B Oxidoreductase
C Hydrolase
A Pyridoxal phosphate
B Magnesium
C Calcium
False
True
True
20