Chap 11 Questions and Answers

Chap 11 Questions and Answers An immunoassay is performed in the following manner to look for an antigen (Ag) in the patient serum: Patient serum + labeled Ag + known antibody (Ab) are added together and incubated. Unbound material is washed off. The amount of labeled Ag is then measured. What assay is performed? Competitive Best describes competitive binding assays A limited number of binding sites are present identity the characteristics associated with non competitive enzyme immunoassays Antibody is bound to the solid phase Best describes homogenous assays A washing step is not necessary Testing situation where there is a direct relationship between the amount of bound label and the amount of patient antigen present 1)Competitive radioimmunoassay using labeled antigen 2)Competitive enzyme immunoassay using labeled antigen 3)Noncompetitive enzyme immunoassay using a second labeled antibody You must choose between two widely accepted, commonly used colorimetric enzyme immunoassay kits to measure a plasma protein that circulates at a moderately high concentration. Each kit uses a different enzyme and substrate. What is the most important consideration in making your choice? Wavelengths detected by microtiter plate reader Which assay is the best choice for measuring small molecules, such as drugs and small peptide hormones? Enzyme multiplied immunoassay technique (EMIT) Point of care testing is performed most easily using Immunochromatographic assay Compared with a capture assay, a radioimmunoassay is likely to be more advantageous in terms of Analytical sensitivity The signal measured in a fluorescence polarization immunoassay is the Orientation of emitted light waves Rheumatoid factor can cause false positive results in which type of assay Heterogeneous noncompetive Extremely high analytical concentrations can cause false negatives results (hook effect) in which type of assay? Heterogenous noncompetitive Statement about noncompetitive enzyme immunoassay is true All patient antigen is allowed to react with binding sites What compound is an appropriate label in chemiluminescent assay Ruthenium derivative In a capture assay to determine the presence of a viral antigen in a patient sample, which of the following would be on a solid phase Unlabeled antibody The use of vitamin of B7 in a delayed capture assay is found in which technique ? Biotin avoiding labeling assay An indirect ELISA assay was performed on a patients serum sample. What is the relationship of the amount of enzyme activity to the amount of patients antibody measured? Directly proportional An immunoassay is performed in the following way: Antigen is bound to a solid support. Patient serum is added, and patient antibodies bind to the antigen. The well is washed, and enzyme-labeled anti-immunoglobulin antibodies are added. The well is washed, and enzyme substrate is added. Enzyme activity is determined. Which immunoassay is described? ELISA When is the enzyme labeled antibody added in the sandwich immunoassay testing technique? Right after incubation stage The "sandwich" inthe sandwich immunoassay testing techniques is between: 2 reagent antibodies To detect low molecular weight analyzes, which immunoassay is best? Homogenous immunoassay A urine drug screen is performed using which technique below? (LO 9, T2) Homogenous immunoassay A out patient physicians office is investigating the addition of a convenient way to perform analysis for a commonly tested analyte where results are often needed before the physician enters the examination room. Which is most appropriate? Rapid immunoassay How is pregnancy testing performed at home? Immunochromatography ------ is more sensitive?this assay is also sensitive enough to detect very low and very high analyte concentrations? Heterogenous chemiluminescense Indirect immunofluorescense is similar to which type of enzyme immunoassay in terms of the performance of the assay? ELISA An antigen is fixed to a microscope slide, then incubated with patient serum. After washing, fluorescently labeled anti-human immunoglobulin is applied. After an additional wash, the slide is inspected with a fluorescent microscope. This technique is called: Indirect immunofluorescence A tissue section is fixed to a microscope slide, then incubated with a flurecently labeled antibody that binds to an antigen expressed by cells in that tissue. The preparation is then washed and inspected with a flurescent microscope. Direct immunofluorescence Which immunoassay provides results indirectly proportional to the concentration of patient antigen present CMLA Therapeutic Drug Monitoring for phentoin is commonly tested using which technique? CMIA Assay format that has the lowest equipment cost Immunochromatography Which assay assay poses the greatest risk of exposure to biohazards Radioimmunoassay Select the technique that would most likely be used to determine the concentration of a therapeutic drug Fluorescence polarization The standard method for detecting antinuclear antibodies (in certain auto immune diseases) is: Indirect immunofluorescence Testing interference that would cause a false positive result? Cross-reactivity Testing interference that would cause a false negative result Postzone effect A benefit to polycrylamide over agarose in gel electrophoresis is Polyacrylamide gel can provide resolution high enough for protein size and charge differentation What is ment by semiconservative replication of DNA? Each strand is the template for another strand For a probe to hybridize to the target, which condition must be met? The target must have complementary bases A ligase is an enzyme that Joins two DNA chains by creating a phosphodiester bond The reaction characterized by amplification of a specific region of a DNA strand through denatured and annealing. Polymerase chain Reaction What method does not require repeated heating and cooling TMA How would you interpret results of DNA restriction analysis by gel electrophoresis if there was a difference in one band? The samples are not identical Which type of RNA is used to directly translate the DNA code into making functional proteins Messenger RNA Which method would work best for detection of a RNA based virus? TMA In DNA sequencing what is the purpose of the dideoxynucleotide bases To stop the growth of a DNA chain at a certain point Which method is most precise for detecting mutations? Chain termination sequencing Select the probe sequence that will hybridize to the following nucleic acid sequence:C G A T A T T G T C G C T A T A A C A G Select the strand of RNA that is complementary to this single strand of DNA? A T T A G C G T A T U A A U C G G C U A U The individual nucleotides along a single strand of DNA are held together by Phosphodiester bonds Complementary strands of the DNA are held together by Hydrogen bonds What process confers specificity in molecular biology methods Hybridization In a qPCR, the threshold cycle represents An indication of the original amount of target in The sample In a polymerase chain reaction, the strand length if the amplicons is determines by the Primer sequences The best method for detecting multiple genotypes of the same virus is Branched DNA amplification Multiple probes bind to target sequences in: Branched DNA amplification The common characteristic of transcription mediated amplification and reverse transcripts polymerase chain reaction is that both Start with an RNA target Strand displacement amplification shares which characteristic with thr polymerase chain reaction Both involve DNA polymerase Which process can be combined with a bead or array format enabling detection of 100 different targets in one sample Hybridization assays Sanger chain termination sequencing differs from polymerase chain reaction because Dideoxynucleotide triphosphates are added Which method is utilized for HLA typing? NGS DNA replication requires which enzymes? DNA polymerase and primase What is the difference between mutation and a polymorphism A mutation can exist in a single person; a polymorphism must exist in at least 2% of the population When denatured, DNA is converted from: a double strand to a pair of single strands. In the process of translation, the addition of a particular amino acid to a growing a protein may be specified by: One of several specific combinations of three mRNA nucleotides What I'd meant by "gating" in flow cytometry? An electronic window separating sub populations of cells A mature cytotoxic T cell expresses which markers? CD8, CD3, and CD2 An intrinsinic parameter that can be measured by a flow cytometer is Granularity As measured in flow cytometry, cells that are the smallest and have the least granules would be identified as: lymphocytes Intrinsic cellular parameters are distinguished by which of the following: FORWARD LIGHT SCATTER The expression of cell surface markers is determined in the flow cytometer by which of the following Fluorescence In flow cytometry, if there are 2 light detectors, what does the amount of side scatter indicate? Granularity of the cell Identify the difference between batch and random access analyzers Batch analyzers only do one type of analysis at a time The lowest measurable amount of an anaylte is called Analytic sensitivity The reference interval is determined by measuring an analyte in samples from a large number of healthy people, using the same instrument or test system. In flow cytometry, the sheath fluid Draws the suspended cells into a laminar flow Best describes the reportable range Span of test result values over which the laboratory can establish or verify the accuracy of an instrument or test system Which light signal in flow cytometry could be used to provide information about the expression of a protein on the other surface of a cell membrane? Red light emitted by phycoerythrin