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Analytes elevated in the morning: *Chloride, phosphorus, potassium and amylase Lactic acid, creatine kinase ACTH, cortisol, iron and aldosterone ACP, growth hormone, PTH and TSHRatio: Diurnal variation ↑ in am: ACTH, cortisol, Fe, aldo sterone ↑ in pm: ACP, growth hormone, PTH, TSHAnalytes elevated ...

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Analytes elevated in the morning: * Chloride, phosphorus, potassium and amylase Lactic acid, creatine kinase ACTH, cortisol, iron and aldosterone ACP, growth hormone, PTH and TSH Ratio: Diurnal variation ↑ in am: ACTH, cortisol, Fe, aldosterone ↑ in pm: ACP, growth hormone, PTH, TSH Analytes elevated when in standing position: * Glucose, insulin, triglycerides, gastrin and ionized calcium ACTH, cortisol and catecholamines Lactic acid, ammonia and blood gases Albumin, cholesterol, aldosterone and calcium Ratio: Posture ↑ When standing: albumin, cholesterol, aldosterone, Ca2+ Most basic pipette: * Automatic pipette Glass pipette Ratio: ROUTINELY USED: automatic pipette MOST BASIC: glass pipette Does not have graduations to the tip: * Mohr pipet Serologic pipet Micropipet None of these Ratio: A Mohr pipet does not have graduations to the tip.It is a self-draining pipet, but the tip should not be allowed to touch the vessel while the pipet is draining.

Pipets are used with biologic fluids having a viscosity greater than that of water: * Mohr pipets Ostwald-Folin pipets Pasteur pipets Volumeteric pipets Ratio: Ostwald-Folin pipets are used with biologic fluids having a viscosity greater than that of water. They are blowout pipets, indicated by two etched continuous rings at the top. Pipette with BULB CLOSER TO THE DELIVERY TIP and are used for accurate measurement of VISCOUS FLUIDS, such as blood or serum: * Ostwald-Folin pipette Volumetric pipette Pipette with cylindrical glass bulb near the CENTER of the pipette that helps to distinguish them from other types of transfer pipettes. * Ostwald-Folin pipette Volumetric pipette Extremely inert, excellent temperature tolerance and chemical resistance; used for stir bars, stopcocks and tubing: * Polyethylene Polycarbonate Polystyrene Teflon Ratio: POLYETHYLENE  Widely used in plastic ware, too, including test tubes, bottles, graduated tubes, stoppers, disposable transfer pipets, volumetric pipets, and test tube racks.  May bind or absorb proteins, dyes, stains, and picric acid POLYCARBONATE  Used in tubes for centrifugation, graduated cylinders, and flasks  Usable temperature range is broad: –100° C to +160° C  Very strong plastic but is not suitable for use with strong acids, bases, and oxidizing agents

 May be autoclaved but with limitations POLYSTYRENE  Rigid, clear type of plastic that should not be autoclaved  Used in an assortment of tubes, including capped graduated tubes and test tubes  Not resistant to most hydrocarbons, ketones, and alcohols TEFLON  Widely used for manufacturing stirring bars, tubing, cryogenic vials, and bottle cap liners  Almost chemically inert and is suitable for use at temperatures ranging from –270° C to +255° C  Resistant to a wide range of chemical classes, including acids, bases, alcohol, and hydrocarbons

Horizontal-head centrifuge: * Cytocentrifuge Fixed-angle head centrifuge Swinging bucket centrifuge Ultracentifuge Ratio: HORIZONTAL-HEAD OR SWINGING BUCKET CENTRIFUGE * HORIZONTAL WHEN MOVING OR SPINNING * VERITICAL WHEN NOT MOVING Cups holding the tubes of material to be centrifuged occupy a vertical position when the centrifuge is at rest but assume a horizontal position when the centrifuge revolves It is used when rapid centrifugation of solutions containing small particles is needed; an example is the microhematocrit centrifuge: * Horizontal-head centrifuge Fixed-angle head centrifuge Ultracentrifuge Cytocentrifuge

High-speed centrifuges used to separate layers of different specific gravities, commonly used to separate lipoproteins: * Horizontal-head centrifuge Fixed-angle head centrifuge Ultracentrifuge Cytocentrifuge Ratio: ULTRACENTRIFUGE High-speed centrifuges used to separate layers of different specific gravities Commonly used to separate lipoproteins Usually refrigerated to counter heat produced through friction Uses a very high-torque and low-inertia motor to spread MONOLAYER OF CELLS rapidly across a special slide for critical morphologic studies: * Horizontal-head centrifuge Fixed-angle head centrifuge Ultracentrifuge Cytocentrifuge Ratio: CYTOCENTRIFUGE Uses a very high-torque and low-inertia motor to spread monolayers of cells rapidly across a special slide for critical morphologic studies Used for blood, urine, body fluid, or any other liquid specimen that can be spread on a slide Calibration of centrifuges is customarily performed every ______. * Daily Weekly Every 3 months (quarterly) Yearly Ratio: Photoelectric tachometer or strobe tachometer CAP recommends that the number of revolutions per minute for a centrifuge used in chemistry laboratories be checked every 3 months

Centrifuges are routinely disinfected on a ___ basis. * Daily Weekly Monthly Quarterly Ratio: Calibration of centrifuges is customarily performed every 3 months, and the appropriate relative centrifugal force for each setting is recorded. Centrifuges are routinely disinfected on a weekly basis.

Water produced using either an anion or a cation EXCHANGE RESIN, followed by replacement of the removed ions with hydroxyl or hydrogen ions. * Deionized water Distilled water RO water The PUREST TYPE OF REAGENT WATER is: * Type I Type II Type III All are equal

HIGHLY PURIFIED SUBSTANCES of a known composition: Control Standard Ratio: A standard may differ from a control in its overall composition and in the way it is handled in the test. Standards are the best way to measure ACCURACY. Standards are used to establish reference points in the construction of graphs (e.g., manual hemoglobin curve) or to calculate a test result.

It represents a specimen that is SIMILAR IN COMPOSITION TO THE PATIENT’S WHOLE BLOOD or plasma: * Control Standard Ratio: The value of a control specimen is known. Control specimens are tested in exactly the same way as the patient specimen and are tested daily or in conjunction with the unknown (patient) specimen. Controls are the best measurements of PRECISION and may represent normal or abnormal test values.

Ratio:  Type I Reagent Water Is used for test methods requiring minimum interference. Is used for procedures that require maximum water purity for accuracy and precision. It should be used immediately (storage is discouraged) after production. it is used for ultramicrochemical analyses,  measurements of  nanogram or subnanogram concentrations, tissue or cell methods (microscopy) and preparation of standard solutions. Use: Flame Photometry, AAS, blood gases and pH, enzyme studies, electrolyte testing, HPLC, trace metal and iron studies.  Type II Reagent Water For hematology, microbiology, immunology and chemistry.  Is acceptable for preparation of reagents and  quality control materials.  Type III Reagent Water For urinalysis, parasitology and histology.  For washing glassware 

Chemicals that are used to manufacture drugs: *

Basic unit for mass: *

Technical or commercial grade Analytical grade Ultrapure grade USP and NF chemical grade

Gram Kilogram Mole Pound

Ratio:

Ratio: BASE QUANTITY 1. Length (meter) 2. Mass (kilogram) 3. Time (second) 4. Electric current (ampere) 5. Thermodynamic temperature (Kelvin) 6. Amount of substance (mole) 7. Luminous intensity (Candela)

 Analytical Reagent Grade (AR) o It is important for qualitative and quantitative analyses; essential for accuracy. o Specifications were established by the American Chemical Society (ACS). o Labels on these reagents either state the actual impurities for each chemical lot or list the maximum allowable impurities (percentage impurities). Use: trace metal analysis and preparation of standard solutions Ultrapure Reagents  o These types of reagents have been put through additional purification steps. o Suitable for techniques that require extremely pure chemicals o These reagents may carry designations of HPLC or chromatographic on their labels. o Example: Spectrogade, nanograde and HPLC pure o Use: chromatography, atomic absorption and immunoassays  Chemically Pure (CP) or Pure Grade o The impurity limitations of this type of chemical are usually not stated – it fails to reveal the tolerance limits of impurities. o Preparation of these chemicals is not uniform. o Purity is usually delivered by measurement of melting point or boiling point. o It is not recommended for research and analytical chemistry unless further purification or a reagent blank is included.  Technical or Commercial Grade o It is used primarily in manufacturing. o It should never be used in clinical laboratory testing.  United States Pharmacopoeia (USP) and National Formulary (NF) o It is approved for human consumption (not injurious to individuals) but may be applicable for laboratory analysis. o Use: drug manufacturing

Equal parts per hundred or the amount of solute per 100 total units of solution: * Dilution Molarity Normality Percent solution Ratio: Concentration or normality. olution o Expressed as equal parts per hundred or the amount of solute per 100 total units of solution. A percent solution can be described as: (1) w/w, which is expressed as weight (mass) per 100 units of weight (g/g). (2) w/v, which is expressed as weight (mass) per 100 units of volume (g/dL). (3) v/v, which is expressed as volume (mL) per unit of volume (mL) Molarity o It is expressed as the number of moles per 1 L of solution. One mole of a substance equals its gram molecular weight. o It represents the amount of solute per 1 kg of solvent. o It is defined as the number of grams equivalent weights per liter of solution. o An equivalent weight is equal to gmw of a substance divided by its valence.

o Valence is the number of units that can combine with or replace 1 mole of hydrogen ions for acids and hydroxyl ions for bases and the number of electrons exchanged in oxidation-reduction reactions. Which of the following is NOT A COLLIGATIVE PROPERTY of solutions? pH Freezing point Osmotic pressure Vapor pressure Ratio: The properties of osmotic pressure, vapor pressure, freezing point, and boiling point are called COLLIGATIVE PROPERTIES. When a solute is dissolved in a solvent, these colligative properties change in a predictable manner for each osmole of substance present:  FREEZING POINT IS LOWERED by −1.86°C  VAPOR PRESSURE IS LOWERED by 0.3 mm Hg or torr  OSMOTIC PRESSURE IS INCREASED by a factor of 1.7 × 104 mm Hg or torr  BOILING POINT IS RAISED by 0.52°C

BIOSFAETY CABINET: 30% recirculated, 70% exhausted. BSC Class II B1

Electrical equipment fire: * Class A Class B Class C Class D Ratio: Fires have been divided into four classes based on the nature of the combustible material and requirements for extinguishment: Class A: ordinary combustible solid materials, such as paper, wood, plastic, and fabric Class B: flammable liquids/gases and combustible petroleum products Class C: energized electrical equipment Class D: combustible/reactive metals, such as magnesium, sodium, and potassium

Type of extinguisher for CLASS A FIRES: 1. Pressurized water 2. Dry chemical 3. Carbon dioxide 4. Halon * 1 and 2 1 and 3 1, 2 and 3 Only 1 Ratio: TYPE OF EXTINGUISHER (Bishop page 47) Class A: Pressurized water and dry chemical Class B: Dry chemical and carbon dioxide Class C: Dry chemical, carbon dioxide and halon Class D: Metal X

All of the following are CROYEGENIC MATERIALS HAZARDS, EXCEPT: * Asphyxiation Fire or explosion Shock Tissue damage similar to thermal burns Ratio: Liquid nitrogen is probably one of the most widely used cryogenic fluids (liquefied gases) in the laboratory.

There are, however, several hazards associated with the use of any cryogenic material: fire or explosion, asphyxiation, pressure buildup, embrittlement of materials, and tissue damage similar to that of thermal burns.

Repetitive strain disorders such as tenosynovitis, bursitis, and ganglion cysts: *

When a person is receiving an electrical shock, all of the following should be done EXCEPT: Pull the person away from the electrical source Turn off the circuit breaker Move the electrical source using a glass object Move the electrical source using a wood object

Cryogenic materials hazards Electrical hazards Ergonomic hazards Mechanical hazards

Ratio: When an accident involving electrical shock occurs: The electrical source must be removed immediately. TURNING OFF THE CIRCUIT BREAKER, UNPLUGGING THE EQUIPMENT, or moving the equipment using a nonconductive glass or wood object are safe procedures to follow.

Ratio: ERGONOMIC HAZARDS The primary contributing factors associated with repetitive strain disorders are position/posture, applied force, and frequency of repetition.

Most common source of light for work in the visible and near-infrared regions: *

Remember to consider the design of hand tools (e.g., ergonomic pipets), adherence to ergonomically correct technique, and equipment positioning when engaging in any repetitive task. Chronic symptoms of pain, numbness, or tingling in extremities may indicate the onset of repetitive strain disorders. Other hazards include acute musculoskeletal injury. Remember to lift heavy objects properly, keeping the load close to the body and using the muscles of the legs rather than the back. Gradually increase force when pushing or pulling, and avoid pounding actions with the extremities.

Deuterium discharge lamp and mercury arc lamp Incandescent tungsten or tungsten-iodide lamp Ratio: The most common source of light for work in the visible and near-infrared regions is the incandescent tungsten or tungsten-iodide lamp. The lamps most commonly used for ultraviolet (UV) work are: * Deuterium discharge lamp and mercury arc lamp Incandescent tungsten or tungsten-iodide lamp

The first step to take when attempting to repair electronic equipment is to: *

Ratio; The lamps most commonly used for ultraviolet (UV) work are the deuterium discharge lamp and the mercury arc lamp.

Check all electronic connections Turn instrument off and unplug it Reset all the printed circuit boards Review instrument manual

Which is the most sensitive detector for spectrophotometry? *

Ratio: Before REPAIR OR ADJUSTMENT of electrical equipment The following should be done (1) unplug the equipment (2) make sure the hands are dry (3) remove jewelry.

Photomultiplier Phototube Electron multiplier Photodiode array Ratio; Because of this amplification, the PM tube is 200 times more sensitive than the phototube. PM tubes are used in instruments designed to be extremely sensitive to very low light levels and light flashes of very short duration.

Reflectance spectrometry uses which of the following?

Low temperature:

Luminometer Tungsten–halogen lamp Photomultiplier tube UV lamp Thermometer to monitor temperature in reaction

Increase in fluorescence Decrease in fluorescence

Ratio: Slide technology depends on reflectance spectrophotometry.

Continuous flow analysis Centrifugal analysis Discrete analysis None of these

For colorimetric determinations, the light source is a tungsten–halogen lamp.

Which of the following light sources is used in atomic absorption spectrophotometry? * Hollow-cathode lamp Xenon arc lamp Tungsten light Deuterium lamp Laser Ratio: The usual light source, known as a hollowcathode lamp, consists of an evacuated gas-tight chamber containing an anode, a cylindrical cathode, and an inert gas, such as helium or argon. Used to measure concentration of LARGE PARTICLES: 1. Nephelometry 2. Turbidimetry 3. Absorption spectroscopy * 1 only 2 only 1 and 2 1, 2 and 3 Ratio: Nephelometry and turbidimetry are used to measure the concentrations of large particles (such as antigen–antibody complexes, prealbumin, and other serum proteins) that because of their size cannot be measured by absorption spectroscopy. Temperature is _______ proportional to fluorescence. * Directly proportional Inversely proportional No effect

Liquids (reagents, diluents, and samples) are pumped through a system of [continuous] tubing: *

Which of the following types of analyzers offers RANDOM-ACCESS CAPABILITIES? * Discrete analyzers Continuous-flow analyzers Centrifugal analyzers None of these Ratio: All three can use batch analysis (i.e., large number of specimens in one run), but only discrete analyzers offer random-access, or stat, capabilities.

Measures of center. * Mean Median Mode

Type of systemic error where the magnitude changes as a percent of the analyte present; error dependent on analyte concentration. * Constant systematic error Proportional systematic error

Measures of spread. * Coefficient of variation Range Standard deviation Systematic errors include: Deterioration of reagents Improper calibration Improper mixing of sample and reagent Instrument drift Mislabeling a sample Pipetting errors Most frequently occurring value in a dataset: * Mean Median Mode Range Ratio: The mode is the most frequently occurring value in a dataset. Although it is seldom used to describe data, it is referred to when in reference to the shape of data, a bimodal distribution, for example. Type of systemic error in the sample direction and magnitude; the magnitude of change is constant and not dependent on the amount of analyte. * Constant systematic error Proportional systematic error Ratio: Constant error: Type of systemic error in the sample direction and magnitude; the magnitude of change is constant and not dependent on the amount of analyte. Proportional error: Type of systemic error where the magnitude changes as a percent of the analyte present; error dependent on analyte concentration.

Difference between the observed mean and the reference mean: * Bias Confidence interval Parametric method Nonparametric method Ratio: Bias: Difference between the observed mean and the reference mean. Negative bias indicates that the test values tend to be lower than the reference value, whereas positive bias indicates test values are generally higher. Bias is a type of constant systematic error.

Ability of a test to detect a given disease or condition. * Analytic sensitivity Analytic specificity Diagnostic sensitivity Diagnostic specificity Ratio: Analytic sensitivity: Ability of a method to detect small quantities of an analyte. Analytic specificity: Ability of a method to detect only the analyte it is designed to determine. Diagnostic sensitivity: Ability of a test to detect a given disease or condition. Diagnostic specificity: Ability of a test to correctly identify the absence of a given disease or condition.

Ability of a test to correctly identify the absence of a given disease or condition. * Analytic sensitivity Analytic specificity Diagnostic sensitivity Diagnostic specificity Ability of a method to detect small quantities of an analyte. * Analytic sensitivity Analytic specificity Diagnostic sensitivity Diagnostic specificity Ability of a method to detect only the analyte it is designed to determine. * Analytic sensitivity Analytic specificity Diagnostic sensitivity Diagnostic specificity Positive predictive value: * Ability of a test to detect a given disease or condition. Ability of a test to correctly identify the absence of a given disease or condition. Chance of an individual having a given disease or condition if the test is abnormal. Chance an individual does not have a given disease or condition if the test is within the reference interval. Ratio: Positive predictive value: Chance of an individual having a given disease or condition if the test is abnormal. Negative predictive value: Chance an individual does not have a given disease or condition if the test is within the reference interval.

Negative predictive value: * Ability of a test to detect a given disease or condition. Ability of a test to correctly identify the absence of a given disease or condition. Chance of an individual having a given disease or condition if the test is abnormal. C...