Cell Quiz Review s1

Chem TB Flashcards Unit 1

1) An individual working in a clinical chemistry possible conflict of interest. laboratory is married to a sales representative who works for a company that sells chemistry laboratory supplies. When the laboratory manager requests a list of needed supplies, cost of supplies, and vendors, this individual only recommends the spouse’s company as the vendor. This is considered to be a: 2) A patient visits her physician stating that her prescribed a genetic variation in drug- painkiller is not working to reduce the pain following her metabolizing enzymes recent surgery. A friend of the patient claims that the same painkiller “worked wonders” to reduce her pain after the same surgery. The physician states that the difference in the effect of the drug might be caused by ____, which is studied in pharmacogenetics. 3) John works in a molecular diagnostics laboratory and confidentiality of patient receives a blood sample that has the name of a close friend genetic and medical printed on the bar-coded label. The genetic test that is information. ordered on the friend’s sample would provide diagnostic information about a disorder that has a poor prognosis, and the test is usually performed by John. He asks a fellow employee to analyze the sample for him and not divulge the results. This ethical issue concerns: 4) Molecular diagnostic testing methods and results can either qualitative or be: quantitative.

5) Clinical epidemiology, which is the study of the selection and interpretation patterns, causes, and effects of health and disease in of laboratory tests. certain populations, has provided the clinical laboratory with methods that evaluate the effects and outcomes of laboratory testing. This allows for a more effective: 6) Analysis of what by molecular diagnostic methods Circulating plasma nucleic provides a measure of processes that are ongoing at the acids time of blood sampling? 7) A healthy individual with no clinical signs or screening for disease in the symptoms of disease visits his physician for a routine absence of clinical signs or physical examination. Blood samples are collected and symptoms. sent to the laboratory. The tests requested on the sample are for general laboratory analyses, including a complete blood count, a panel of general chemistry tests (including glucose, protein, cholesterol, and others), and an analysis of urine. This type of testing in laboratory medicine is directed at: 8) The discipline involved in laboratory medicine. the selection, provision, and interpretation of diagnostic testing that uses primarily samples from patients is:

1 Chem TB Flashcards Unit 1

9) A male laboratorian works in the clinical chemistry Resource allocation, laboratory of a large hospital. He is approached by his maintenance of friend, who is a representative of a drug company, and confidentiality, conflict of asked to analyze some patient samples for drug levels of a interest, and publishing specific drug that the representative’s company sells and issues. that these patients use. The representative wants to publish a report on the rate of drug absorption and distribution of this drug and tells his laboratorian friend that he will personally reimburse him for his time. What ethical issues come into play here? 10) A statistic is a: value calculated from the observations in a sample to describe a particular characteristic of that sample.

11) A population mean (µ) is calculated by what xi/N formula? 12) What is the correct formula for calculating the CV = (standard deviation ÷ percent coefficient of variation of a set of measurements? mean)  100% 13) The type of method comparison that compares Bland-Altman difference the average results between two analyses with the plot. differences between varying concentration values of the two analyses is referred to as a(n): 14) How is the formula for population standard The positive square root of deviation (σ) stated? the [(sum of squared differences between mean and individual values) ÷ N] 15) Two types of error may be encountered during systematic analysis of a substance. The type of error that occurs with a constant or predictable difference or trend, either positive or negative, and thus is related to bias, is a(n) _____ error. 16) A research project examining cholesterol values 2.19%. using a new Cholestcheck assay produces the following cholesterol values from a random sample of 14, 25-year- old women: Mean = 137 mg/dL 2 standard deviations = 6 mg/dL N = 14 The coefficient of variation percent for this assay is: 17) You are performing a precision study on a new reproducibility chemistry analyzer in your hospital lab by analyzing a single sample many times. The study involves performing the analysis on different shifts using different calibrators and analysis by different laboratorians. This aspect of precision is referred to as:

18) Following a precision study in which 2 2  within-run +  between-run repeatability and reproducibility of 20 samples are assessed, what formulae would be used to determine the total standard deviation (σ2T)? 19) The ability of an analytical method to assess analytical sensitivity. small variations of the concentration of an analyte, and that is often expressed as the slope of the calibration curve, is referred to as: 20) Method selection involves consideration of Analytical performance several different criteria. Assessment of a candidate criteria method’s precision, accuracy, and analytical specificity are components of what categories? 21) The statistical analysis used to compare values regression analysis. obtained by a new method with those obtained by an established method is: 22) The Student t distribution: compares the means of two samples using sample statistics. 23) A list of intervals followed by a list of frequency distribution. frequencies is referred to as a: 24) The type of regression analysis that is Deming considered to reliably estimate the relationship between modified target values and that takes into account errors in both methods 1 and 2 is _____ regression analysis. 25) Comparisons of measurement values between traceability. clinical laboratories require a hierarchical approach that obliges routine clinical chemistry measurements to be referred back to a reference measurement procedure. This concept is known as: 26) To systematically assess errors associated with uncertainty. laboratory results, a parameter associated with the result of a measurement that characterizes the dispersion of the values reasonably attributed to the substance being measured is considered. This parameter is expressed by a formula that includes preanalytical, analytical, and traceability components and is referred to as: 27) In a chemistry methods analysis, linearity refers relationship between to the: measured and expected values over the range of analytical measurements. 28) In the calibration hierarchy, a reference Pure random error measurement procedure, which is a fully understood procedure of highest analytical quality, is at the top. This procedure is associated with what types of error?

29) In a qualitative point-of-care test, clinical probability of classifying a sensitivity is considered as the: result as positive. 30) True negatives ÷ (false positives + true specificity. negatives) is the formula for determining: 31) The proportion of a population that has the prevalence. particular disease being studied is referred to as the: 32) What is the positive predictive value of a test in 83% which 220 tested individuals with positive test results actually have the disease and 45 tested individuals with positive test results do not have the disease? 33) In regard to the number of true-positive and true positives. negative, and false-positive and negative, results in laboratory testing, the prevalence times the sensitivity is equal to the number of: 34) Calculate the sensitivity for the following data: 90%. in a group of 90 patients diagnosed with sickle cell disease, 81 tested positively for it. The sensitivity of this test is: 35) A receiver operating characteristic (ROC) curve true positives versus false is a plot of: positives. 36) ROC curves are most useful in assessing the they can display performance of quantitative laboratory analyses because: performance of tests over the entire range of decision values. 37) A laboratory analysis that produces quantitative continuous results with an infinite number of sensitivity and specificity pairs is referred to as a _____ test. 38) Nondiseased individuals that are classified as false positives. diseased by having a positive result on a specific laboratory test are considered: 39) Combination testing involves the use of falsepositive results multiple laboratory tests in an attempt to decrease costs or increase. assist in diagnosing a specific disease. One of the problems with this type of testing is that: 40) A method that can be used to calculate the Bayes theorem. probability of a disease after new information is added to previously obtained information involves: 41) To calculate the sensitivity of a laboratory test true positives and false to correctly classify true positives, one must first know the negatives. number of: 42) To calculate the predictive value of a positive Sensitivity, specificity, and test, what should be known? prevalence 43) The probability of occurrence of a specific test likelihood ratio. value given that the disease is present divided by the probability of the same test value if the disease was absent is the:

44) Systematic reviews are used to assess and formulation of the clinical answer very specific clinical questions in an unbiased question that will form the way. The most important of the steps in conducting a basis of the review. systematic review is the:

45) In reading a research internal validity. article, you determine that the study design was flawed because there was no control group. This is an example of a weakness in: 46) When developing clinical practice guidelines, Selecting and refining the what is the critical first step? topic upon which the investigation will center 47) Another way that “bias” can be defined is as systematic _____ error. 48) Internal validity is the: degree to which the variables in the study apply to all individuals in the study. 49) During diagnostic accuracy studies in evidence- index test. based laboratory medicine, a laboratory test being studied, for example, produces results that are compared with the gold standard of testing, which would be the currently used assay or assay system. The test of interest is referred to as a(n): 50) A research study was prepared to assess the Systematic error increased. diagnostic accuracy of a therapeutic drug monitoring assay for HMG-CoA reductase inhibitors (statins). The study was flawed with poor design. What statements are correct? 51) In a randomized control trial, the use of a new patient outcome. vaccine was observed to reduce the number Chlamydia trachomatis infections in a population of college-aged women. This finding is referred to as a(n): 52) If the evidence overwhelmingly points toward Clinical audit the introduction of a new laboratory analysis and practice, yet physicians fail to incorporate the new test into their clinical practice, what component of evidence-based laboratory medicine will reveal this? 53) In a research study, a physician asks if the prognostic value study. results from the therapeutic drug assay will be able to predict the patient’s eventual health outcome. A study to determine this is referred to as a: 54) Following a systematic review, random control Developing a clinical studies, clinical audit, and a cost evaluation, an assay for practice guideline for assessment of growth hormone level as a predictor of bone implementation of the assay cancer has been recommended by a group of orthopedic

surgeons to be performed in your chemistry laboratory. What is the next step before implementation of the assay?

55) Following a systematic review, random control This specialty group of studies, clinical audit, and a cost evaluation, an assay for physicians might be assessment of growth hormone level as a predictor of bone motivated to implement this cancer has been recommended to be performed in your test to produce income for chemistry laboratory. What might be an issue if the group the group practice. recommending this assay was composed of all oncologists? 56) STARD: includes a listing of items that need to be included in reports of studies on diagnostic accuracy. 57) QALY: is an outcome achieved in cost-utility analysis. 58) In a study of diagnostic accuracy, the selection External validity of the study groups was not random and included only a few individuals in each group. This would likely affect what? 59) Even if somewhat impractical, what The method of specimen preanalytical factors should be standardized when collection establishing a reference interval for an analyte? 60) To determine the confidence intervals of nonparametric testing. percentiles of ranked data (data arranged by magnitude of value), it is most appropriately assessed using: 61) True negatives ÷ (false positives + true clinical specificity. negatives) ´ 100 is the formula for determining: 62) Calculate the clinical sensitivity for the 90%. following data: in a group of 80 patients diagnosed with sickle cell disease, 72 had positive test results. The clinical sensitivity of this test is: 63) What is an example of an exclusion criterion Use of oral contraceptives when establishing a healthy population-based reference interval? 64) An important assumption that is made when the true distribution that the using parametric methods to estimate percentiles and their reference values exhibit is confidence intervals in determining reference limits is Gaussian. that: 65) A physician asks your laboratory to begin Changes in a subject-based performing thyroid-stimulating hormone (TSH) analyses reference value might on all specimens that have a free thyroxine (FT4) analysis indicate altered biochemical

ordered, a practice that your laboratory currently does not status yet still be within the perform. Your laboratory typically performs TSH only on population-based healthy those FT4 specimens that are outside the population-based reference interval. reference interval. The physician suggests using subject- based reference intervals, claiming that population-based intervals are clinically insensitive. What is the basis of this claim? 66) What is the statistical range of the following 8 distribution of data? 21 25 18 20 19 21 23 26 67) The proportion of a population (or of those prevalence. being tested) with the disease being studied is referred to as the: 68) To reduce workload in your chemistry Yes, if certain conditions laboratory, you are setting up a small laboratory on the have been fulfilled, such as opposite side of your large city from the main laboratory. population matching, data When preparing the new laboratory’s chemistry analyzer, comparison, analytical you decide to use the reference values that have been performance agreement, and generated by the main laboratory’s chemistry analyzer, specimen standardization. which is a larger model (but similar in all other respects) than yours. Can this be justified? 69) Visually inspecting the distribution of reference Outlier values values can provide a safeguard against misinterpretation of statistical methods, and it may provide valuable information about the data. What observations might represent erroneous values? 70) The results of a certain type of quantity reference values. obtained from a single individual or group of individuals corresponding to a stated description is the definition of: 71) When a coagulated blood sample is separated liquid component with no by centrifugation, the liquid component is separated from clotting factors in it. the cells. This “serum” is the: 72) An example of an uncontrollable preanalytical an individual’s age. variable would be: 73) The best use of a saliva specimen would be for Measurement of blood what analyses? group substances to determine secretor status and genotype 74) Hemolysis will cause potassium _____ when and lactate dehydrogenase analyzed. (LD) values to appear increased 75) The type of urine specimen that is best for clean, early morning, fasting detection of abnormal amounts of certain analytes such as specimen. chorionic gonadotropin for pregnancy testing is a: 76) Arthrocentesis is a technique used to collect: synovial fluid. 77) An amniotic fluid specimen for bilirubin Because the tube is not analysis is received in the laboratory in a clear plastic darkened, light will cause

collection tube. How will this affect the results of the the bilirubin to be photo- bilirubin analysis? degraded and the results will be falsely decreased. 78) As an anticoagulant, heparin acts to: activate antithrombin. 79) What anticoagulants is considered unacceptable Heparin for a blood sample that will be used for DNA amplification in the polymerase chain reaction?

80) An individual has several laboratory tests Total protein will be ordered and is having blood collected. After applying the increased and potassium tourniquet, the phlebotomist has to answer the phone and will be decreased. write down a message, leaving the tourniquet in place for approximately 3 minutes. How will this affect this individual’s serum composition of total protein and potassium? 81) An individual has several laboratory tests It will be increased. ordered and is having blood collected. After applying the tourniquet, the phlebotomist has to answer the phone and write down a message, leaving the tourniquet in place for approximately 3 minutes. How will this affect this individual’s serum composition of bilirubin? 82) What analytes shows no difference in Cholesterol composition between a serum and a plasma specimen? 83) A blood collection tube There will be a significant containing a specific amount of additive is only half filled effect on the test results with blood instead of being completely filled. Will this because the additive must collection affect laboratory test results? be mixed with a full tube of blood to achieve its appropriate effect. 84) When collecting a timed urine specimen for the individual’s bladder laboratory analysis: must be emptied first at the beginning of the time of collection, and this urine is discarded. 85) A skin puncture of an individual’s finger is Warm the finger for 3 ordered for hematocrit analysis and is to be collected into minutes using a warming a capillary tube. It is cold in the phlebotomy area, and the device. phlebotomist notices that the individual appears cold and pale. What should the phlebotomist do to stimulate blood circulation to the finger so an acceptable fingerstick specimen will be obtained? 86) An example of a preanalytical error would be: mislabeling a tube of blood with an incorrect name. 87) The best additive in a collection tube for acid citrate dextrose.

enhancing the vitality and recovery of white blood cells for isolation of genomic DNA is: 88) If alerted to a control problem when using assess the analytical Westgard multirules, an analyst should first: method, equipment, reagents, and specimens. 89) Upon examination of the week’s analytical run 41s; systematic of plasma glucose tests, you notice that four consecutive normal control values are +1 s (standard deviation) from the mean. In your QC report, you note that Westgard multirule _____ has been broken and realize that this rejection rule is sensitive to _____ error. 90) Upon examination of the week’s analytical run improper calibrator of plasma glucose tests, you notice that four consecutive preparation. normal control values are +1 s (standard deviation) from the mean. In your QC report, you note that a Westgard multirule has been broken and realize that this rejection rule is sensitive to a specific type of error. An example of this type of error would be: 91) Preparation of a CLSI-defined procedure Analytical document of an analytical protocol is a means of controlling what types of variables? 92) What would be considered a postanalytical Result reporting variable in regard to laboratory services? 93) The Westgard multirules for quality control two consecutive control were designed to interpret control data and to aid in values have exceeded the troubleshooting. The rule stated as 22s is interpreted as mean ±2 s. meaning: 94) Lean Production: is a quality process that focuses on creating more value by eliminating activities that are considered wasteful. 95) What would be considered a cost of Repeating an analytical run nonconformance? because the QC is out of range 96) Six Sigma processes: are quality performance goals that require a specific number of standard deviations of process variation to fit within the tolerance limits for the process. 97) Upon examination of the control chart of the 100; systematic week’s analytical run of serum creatinine, you notice that 10 consecutive level II control values lie on the same side of the mean. In your QC report, you note that Westgard

multirule _____ has been broken and realize that this rejection rule is sensitive to _____ error. 98) Upon examining a Levey-Jennings control chart R4s and 13s for analyte X, you notice that on day 6 the one control was −2.5 s from the mean and the duplicate control was +3.3 s from the mean. What Westgard control rules was/were broken?

99) What statements concerning the use of internal Serum controls are prepared control materials is incorrect? from human serum pools and are analyzed in analytical runs that are separate from patient samples. 100) In regard to a Gaussian distribution, ±2 s from 95.5% the mean encompasses _____ of values. 101) Random error would be caused by: pipetting errors. 102) According to CLIA regulations, a score of 80% _____ must be attained on three consecutive external proficiency test challenges for a laboratory to be accredited and continue patient testing. 103) You have received your proficiency test results 0.67 SDI from the accrediting agency and note that your creatinine result was unacceptable at greater than 2 SDI from the group mean. The value that was entered on your survey report form was 15 mg/dL. The group method mean was 1.3 mg/dL, with a method standard deviation of 0.3 mg/dL. You realize that your laboratory made an error in entering the result. The result was actually 1.5 mg/dL, using this corrected result what would the correct SDI be? 104) You have received your proficiency test results Yes from the accrediting agency and note that your creatinine result was unacceptable at greater than 2 SDI from the group mean. The value that was entered on your survey report form was 15 mg/dL. The group method mean was 1.3 mg/dL with a method standard deviation of 0.3 mg/dL. You realize that your laboratory made an error in entering the result. The result was actually 1.5 mg/dL, would the recalculated SDI now be in agreement with the rest of the laboratories in the testing program? 105) Two types of error may be encountered during systematic chemical analysis of a substance. The type of error that

occurs as a result of contaminated calibrating solutions would be _____ error.

106) You arrive at the clinical chemistry laboratory D one morning and discover that personnel from the third shift left you the QC sheet from the thyroid-stimulating hormone (TSH) run. The technician has circled the level I TSH control values, and you realize that all six of the level I control values are +3 s from the mean. No results have been released. Now it’s your decision regarding what to do next. First, which Westgard rule(s) has (have) been violated? A. 22s B. 41s C. 13s D. All of the above rules have been broken. 107) You arrive at the clinical chemistry laboratory Hold all results, reject the one morning and discover that personnel from the third run, and troubleshoot. shift left you the QC sheet from the thyroid-stimulating hormone (TSH) run. The technician has circled the level I TSH control values, and you realize that all six of the level I control values are +3 s from the mean. No results have been released. Now it’s your decision regarding what to do next. What is your decision regarding the release of 108) You arrive at the clinical chemistry laboratory Systematic error due to one morning and discover that personnel from the third calibration issues shift left you the QC sheet from the thyroid-stimulating hormone (TSH) run. The technician has circled the level I TSH control values, and you realize that all six of the level I control values are +3 s from the mean. No results have been released. Now it’s your decision regarding what to do next. What kind of error is most likely occurring? 109) According to the five-Q framework, the “QP” planning. refers to quality: 110) What is the role of quality planning in the five- To ensure that the Q framework of quality? laboratory's performance satisfies quality

requirements 111) The first step in the development of an in- a needs assessment or gap service training program using an instructional system for analysis. employee competency in the laboratory is: 112) To make 20 mL of a 0.1 g/L solution from a 10 0.2; 19.8 mg/mL stock solution, you should add _____ mL of the stock solution to _____ mL of solvent. 113) What statements concerning type I water is not Type I water is obtained correct? from distillation only and contains a few impurities.

114) What is the relative centrifugal force (RCF) for 32.7 g a centrifuge spinning at 1200 rpm with a rotor head radius of 8 inches? 115) Reverse osmosis is: a process by which water is forced through a semipermeable membrane that acts as a molecular filter. 116) The National Institute for Occupational Safety Universal Precautions. and Health of the CDC distributes a document that specifies how U.S. clinical laboratories should handle infectious agents. This document is referred to as: 117) A highly purified chemical that is directly primary reference material. weighed or measured to produce a solution whose concentration is exactly known is referred to as a: 118) Chemicals with the designation _____ are analytical reagent grade suitable for use in most clinical chemistry laboratory analyses. 119) What is the molarity (mol/L) of a solution 1.7 mol/L containing 25 g of H2SO4 (MW= 98 g) in 150 mL of deionized water? 120) How many grams of NaCl (MW = 58.5 g) are 87.75 g required to prepare 250 mL of a 6 mol/L solution of NaCl? 121) What is the normality of a 0.82 N solution containing 20 g of H2SO4 (MW = 98) in 500 mL of buffer? 122) Universal Precautions: consist of guidelines that in part necessitate the wearing of barrier protection when handling potentially infectious material. 123) You have seen another laboratorian collecting Universal Precautions blood from a patient without using any barrier protection.

What safety mandate is this employee ignoring? 124) The one technical aspect of a clinical laboratory pipetting. that has received considerable attention in the need for ergonomic design to decrease musculoskeletal stress would be: 125) Regarding centrifugation, what is the formula RCF = 1.118  105  r (in for calculating relative centrifugal force (RCF)? cm)  rpm2 126) Fifty milligrams (mg) per 1000 mL is equal to: 0.050 g/L 127) What is the Clinical and Laboratory Standards 1200 g for 10 min Institute (CLSI) recommendation for the most appropriate RCF and time for centrifugation of blood samples to obtain sufficient separation of cellular and liquid components? 128) The class of fire that involves flammable liquids dry chemical or carbon and gases is class and the recommended extinguisher dioxide. agent is: 129) The type of pipette that is a piece of glass measuring pipette. tubing drawn out to a tip and graduated uniformly along its length and is used for reagent measurement is referred to as a: 130) The increased use of electronic health record Logical Observation (EHR) systems has amplified the need for standardized Identifier Names and Codes communication between EHR and other systems. The system. newest universal code system that has standardized terms for all kinds of laboratory observations and measurements and includes a code number, a long formal name, a shorter name, and synonyms is referred to as the: 131) In regard to absorption photometry, absorbance A =  log T is calculated from transmittance by what formulae? 132) What statements best describes Beer law? The concentration of a substance is inversely proportional to the logarithm of transmitted light. 133) There are several interferences that can affect or occurs when the solution limit fluorescence measurements. For example, the inner absorbs greater than 2% of filter effect: the exciting light, producing a nonlinear response between concentration and fluorescence emission. 134) A molecule is said to fluoresce when it absorbs a lower energy. light at one wavelength and emits light of: 135) In regard to atomic absorption (AA) The technique measures spectrophotometry, what statements is correct? concentration through the detection of absorbance of electromagnetic radiation by

atoms of elements instead of molecules. 136) What statements concerning nephelometry is In a nephelometric correct? procedure, the measurement of scattered light that is not in the direct path of the transmitted light is made at right angles to the incident light. 137) A blood specimen is obtained from an The lipemic specimen will individual who is known to have elevated lipids and the produce interfering serum appears milky. This individual’s physician has background light intensity ordered an estrogen immunoassay that your laboratory and excess light scatter in performs using a nephelometric technique. What this type of assay. statements is correct concerning the possible outcome of this assay?

138) A monochromator’s filter must be tested to spectral bandwidth. determine whether it can isolate a specific part of the electromagnetic spectrum. Percent transmittance (%T) of light is plotted against a specific wavelength in nanometers. It is noted at which wavelengths 50%T (one half of the peak transmittance) occurred. This type of test assesses the filter’s: 139) A manual stat protein analysis is performed on a 7.2 g/dL patient sample. The patient’s unknown sample had an absorbance reading of 0.6. The protein calibrator with an absorbance reading closest to the unknown's absorbance had a concentration of 6 g/dL and an absorbance reading of 0.5. Applying Beer law, calculate the unknown protein concentration in the patient sample. 140) What would be a limitation in a nephelometric Excess antigen in the measurement that might produce faulty values? antigen/antibody reaction 141) In spectrophotometric determinations, what is Molar absorptivity  length the formula for calculating the absorbance of a solution? of light path  concentration in mol/L 142) A standard calibrator solution of glucose has a 150 mg/dL concentration of 125 mg/dL and gives an absorbance of 0.20. Assuming a linear reaction, what is the concentration of glucose in a patient’s serum that has an absorbance of 0.24? 143) What wavelengths is within the “near” 320 nm ultraviolet region of the electromagnetic spectrum?

144) Laboratory analysis of free thyroxine (fT4) in The dilution of the sample your chemistry laboratory is performed with a has lowered produced conventional fluorometric analyzer, which uses a laser photobleaching by the

light as the excitation source. You have received a sample intense light source and from an individual known to have a very elevated fT4 photodecomposition of the level. For the sample’s value to be within linear range of analyte. the assay, you dilute the sample by a factor of 10 and proceed with the analysis. Upon reviewing the results, you note that the value of the diluted sample is reported as “none detected.” What is the likely reason for this result? 145) A fluorometric measurement technique used to fluorescence polarization. detect immunologic reactions that measures fluorescence produced by the rotation of small versus large fluorescent- labeled molecules and their relation to analyte concentration in an unknown sample is known as: 146) Which component of a generic Monochromator spectrophotometer isolates radiant energy of a specific wavelength (spectral isolation) and excludes that of other wavelengths?

147) Atomic absorption spectrophotometry is an elements. emission technique that is used frequently in clinical laboratories to measure: 148) The light source in an atomic absorption hollow cathode tube. spectrophotometer is typically a: 149) When selecting a photometric technique that is Fluorescence intensity more sensitive to a low concentration of analyte, a measurements are more laboratory director compares absorbance measuring sensitive because of the use devices against those that measure fluorescence intensity. of intense light sources, Which technique is considered more sensitive in its signal filtering, and measurements and why? sensitive light emission photometers. 150) What components is found only in a An excitation source fluorometer used to make measurements of emitted fluorescent light as opposed to in a spectrophotometer used to make measurements of absorbed/transmitted light? 151) What optical techniques is not considered an Nephelometry emission technique? 152) Which two optical techniques are combined Laser-induced fluorometry operationally in a flow cytometer? and light scattering techniques 153) A light-beam chopper in a double-beam-in-time compensate for light source spectrophotometer is used to variation. 154) In a fluorometric measurement, the difference the Stokes shift. between the maximum wavelength of the excitation light and the maximum wavelength of the emitted fluorescence light is a constant referred to as: 155) A physician is concerned about an emphysema Amperometric method patient’s PO2 level and wants to determine it in this

patient’s blood. What would be best used to determine PO2? 156) A commonly used electrode also used as an Silver/silver chloride internal reference electrode in ion-selective electrode measurements is what? 157) Measurement of pH involves which kind of Hydrogen redox electrode electrode? 158) An electrochemical technique used to measure coulometry. chloride in serum or plasma is: 159) The measurement of the voltage difference potentiometry between two half-cells immersed in solution is referred to as: 160) What voltage potentials occurs as the result of Redox potential chemical equilibrium involving electron transfer reactions? 161) A commonly used glass electrode that is used as Calomel a reference electrode in pH measurements is the _____ electrode.

162) A PCO2 electrode: is a potentiometric cell in which carbon dioxide gas from the sample diffuses through a membrane and forms carbonic acid. 163) Incorporation of _____, a neutral antibiotic, into valinomycin a polyvinyl chloride membrane allows for the manufacture of an ion-selective electrode that is highly selective for potassium. 164) The type of ion-selective electrode mentioned in polymer membrane the preceding question is in a category of electrodes referred to as _____ electrodes. 165) What is not measured with an enzyme-based DNA segments biosensor, with a light sensing fiber optic probe? 166) What conditions are among the requirements for A concentration gradient for a Nernst equilibrium potential to exist for a given charged a given charged ion species ion species across a semipermeable membrane as in an must exist across that ion-selective electrode? membrane. 167) A biosensor that uses both enzyme detection urea using urease and the and an ion-specific electrode could be examining: production of ammonium ions. 168) In an optical sensing (optode) system for the The decrease in intensity of measurement of PO2 using fluorescence, what is being an organic dye’s measured? fluorescence in the presence of molecular oxygen, which is proportional to the PO2

169) Potentiometric measurements are based on two electron or metallic galvanic electrochemical cells. These types of cells consist conducting electrodes that of: are connected by an electrolyte solution that conducts ions. 170) In electrophoresis, the best support medium to polyacrylamide. use because it is thermostable, strong, transparent, and eliminates endosmosis due to the lack of a charge is: 171) The component of an electrophoresis system buffer. that carries the applied current and establishes the pH at which electrophoresis is performed is the: 172) Upon receiving a serum sample for protein There would be an electrophoresis, which you perform using agarose gel, you increased β-globulin band. note that the specimen is hemolyzed. How would hemolysis affect the banding pattern of this type of electrophoresis? 173) What is the importance of the ionic strength of A heat-labile protein will the buffer used in gel electrophoresis? become denatured if the ionic strength of the buffer is too high. 174) On a serum protein electrophoresis, if the sample overload. albumin band appears distorted and large, the likely cause is: 175) If the viscosity of the support medium used in a decrease. protein electrophoresis system is too high (thick), the rate of migration will: 176) You have just set up the morning protein The current or voltage on electrophoresis. When you return 45 minutes later, you the power supply was set stain the gel and notice that the bands did not migrate very too low. far from the point of application. What is the likely explanation? 177) In an electrophoresis system, the _____ is the cathode negative electrode. 178) The process of transferring the electrophoresed Southern blotting. DNA fragments out of a gel and onto a special nylon paper is referred to as: 179) What stains are used to stain a serum protein Amido Black and electrophoresis gel? Coomassie Brilliant Blue 180) What would the concentration of albumin be if 4.68 g/dL the total protein value was 8.5 g/dL and the densitometer measured the albumin fraction as 55% of the total? 181) The main advantage of capillary electrophoresis more efficient heat over standard gel electrophoresis is: dissipation for better separation. 182) If the viscosity of the support medium used in a decrease. protein electrophoresis system is too high (thick), the

migration rate will: 183) A separation technique that can detect proteins Northern blotting. in a complex mixture with the use of antibodies directed against a protein of interest is: 184) In capillary electrophoresis, hydrodynamic involves sample injection sample injection: into the capillary by applying a positive pressure to the sample inlet. 185) A type of electrophoresis that provides isoelectric focusing increased resolution in protein separation by allowing the protein to migrate to a point where the protein’s charge becomes zero and its migration stops is _____ electrophoresis. 186) The isoelectric point (pI) of a protein is the pH has no net charge. at which the protein: 187) Endosmosis: is the movement of solvent along with highly hydrated ions to produce the driving force in capillary electrophoresis.

188) You are examining a protein electrophoresis A plasma sample was pattern and notice an unusual band at the starting point of probably applied instead of the electropherogram that is not present in the normal serum. control. If the patient were healthy, what is the most likely cause of the unusual banding pattern? 189) The theory of electrophoresis states that: ionized chemical species having an electrical charge move toward either the cathode (negative electrode) or the anode (positive electrode). 190) In the isolIn the isolation of nucleic acids from blood Size-exclusion samples, a step is typically performed to separate large molecules, such as proteins and nucleic acids, from smaller molecules such as salts. Which type of separation mechanism would best be suited for this task? The type 191) The type of separation mechanism for chromatography that affinity involves, as one example, use of immunologic principles is _____ chromatography. 192) In the thin layer chromatography procedure for drug ratio of distance moved by screening, the retention factor (Rf) value for a compound is the unknown solute to given by the: distance moved by the solvent in the mobile phase. A toxico 193) A toxicology screen is set up using thin layer 0.23, 0.43, 0.63

chromatographic plates. Four positive controls/standards are used with the following distance of migration from application point results: Std A = 8 cm; Std B = 15 cm; Std C = 22. The acetone solvent front moved 35 cm. After processing an unknown sample, a solute had a migration distance of 16 cm. What are the retention factors (Rf) of standards A, B, and C?

A toxicol 194) In the above question, what is the Rf of the unknown 0.45 solute? 195. 195) A measure of peak separation in a chromatographic resolution. method that equals the difference in retention time for two components divided by the average of their peak widths is the definition of:

196. 196) Examine the following HPLC chromatograms, both of Chromatogram A which were obtained from the same sample: A B

Which chromatogram has the best resolution because of increased separation or chromatographic efficiency? 197. 197) What improvements could be made to increase the Using smaller particles in chromatographic (separation) efficiency of a poorly resolved the stationary phase HPLC separation? 198. 198) In HPLC, analyte detectors can consist of fluorometers, monitoring the current that photometers, and electrochemical detectors. An electrochemical is generated by oxidation or detector measures an electroactive analyte by: reduction reaction under a constant potential voltage and that is proportional to the concentration of analyte. 199. 199) You are preparing placental tissue for separation and Ion-exchange

isolation of a specific enzyme. The enzyme has a negative charge, so you want to use chromatography to perform your task. What chromatographic separation mechanisms would be most useful? 200. 200) A type of detector used in GC that is universal in its thermal conductance detection of compounds but has low sensitivity compared with other detectors is a(n) _____ detector. 201. 201) In partition chromatography, separation is based on: the differences in the relative solubility of compounds between the stationary and mobile phases. 202. 202) In clinical applications using gas chromatography, what Temperature programmed column temperature techniques will cause the more volatile operation analytes to elute first and produce the best separation of mixtures of analytes with a range of volatilities? 203. 203) What component of an HPLC introduces an aliquot of A fixed-loop injector with a sample into the column and how is this introduction switching valve moves the accomplished with the high pressure in the flow path? sample into the flow path.

204. 204) Some analytes must be derivatized to increase their adding fluorescent labels or column retention or detectability. Derivatization means: combining the analyte with chiral reagents or other chemicals to increase detectability. Match the color of the evacuated blood collection tube stopper 205. Green with the additive in that tube. 206. Lavender 1. 205. Heparin 207. Yellow 2. 206. EDTA 208. Gray 3. 207. Acid citrate dextrose 4. 208. Glycolytic inhibitor 209) True or False? Molecular diagnostics testing is only used False by the clinical chemistry laboratory. 210) True or False? In regard to clinical evaluation of method, a True high clinical sensitivity means few false negatives. 211) True or False? The maximum amount of working volume False of a flammable solvent allowed outside a storage cabinet is 1 gallon per room. 212) True or False? The visible spectrum is composed of those True wavelengths between 380 and 750 nm. 213) True or False? Thin layer chromatography is a type of False planar chromatography with separation based on the principles of partition chromatography. 214) True or False? In column chromatography, analytes are True

20 Chem TB Flashcards Unit 1 identified by their retention times.