Chemistry Exams

Which of the following is the major mineralocorticoid? A. Aldosterone B. Cortisol C. Corticosterone D. Testosterone

A - Aldosterone

Energy or frequency of light waves varies ____________ with the wavelength. A. Inversely B. Directly

A - Inversely

Urea: A. Is synthesized in the liver from the breakdown of nucleic acids B. Is synthesized from CO2 and ammonia C. Can produce Reye's syndrome when present in high amounts in blood D. Is increased in serum during acute episodes of gout

A - Is synthesized in the liver from the breakdown of nucleic acids

True or false? Serum uric acid levels may be elevated in patients undergoing cancer chemotherapy. A. True B. False

A - True

Convert 10 mg/dL of calcium to mmole/L. (mw = 40) A. 2.5 B. 5 C. 10 D. 25

A. 2.5 Calculation:

One cause for a DECREASED "anion gap" is: A. A decrease in albumin B. A decrease in calcium C. An increase in organic acids D. An increase in phosphate

A. A decrease in albumin

Given the following lab results, what is the most likely cause of this patient's BUN?BUN 45 mg/dLCreatinine 1.8 mg/dLUric Acid 7 mg/dLpH 7.22pCO2 74.4 mm HgpO2 32.8 mm HgO2 sat. 51.3% A. Congestive heart failure B. Chronic renal disease C. Dialysis D. Acute tubular necrosis

A. Congestive heart failure

Match the disease with the cause: A. Deficiency of branch-chained keto acid decarboxylase B. Deficiency of phenylalanine hydroxylase C. Defect in enzyme tyrosine D. Defect in fumarylacetoacetase E. Increased excretion of cysteine due to defect in renal absorption F. Deficiency in homogentisate oxidase

A. Cystinuria B. Phenylkentonuria C. Albinism D. Maple syrup urine disease E. Tyrosinemia F. Alkaptonuria

Which of the following condition is associated with hypernatremia? A. Diabetes insipidus B. Hypoaldosteronism C. Burns D. Diarrhea

A. Diabetes insipidus

Porphobilinogen may be differentiated from urobilinogen in urine by: A. Difference in chloroform solubility of Ehrlich's aldehyde derivatives B. Difference in reactivity with Ehrlich's aldehyde reagent C. Difference in fluorescence of Ehrlich's aldehyde derivatives D. Difference in precipitation with ammonium sulfate

A. Difference in chloroform solubility of Ehrlich's aldehyde derivatives

A patient is admitted to the emergency room in a state of metabolic alkalosis. Which of the following would most likely be consistent with this diagnosis? A. High pCO2, increased HCO3 B. Low pCO2, increased HCO3 C. High pCO2, decreased HCO3 D. Low pCO2, decreased HCO3

A. High pCO2, increased HCO3

In rickets patients, typical findings include all of the following EXCEPT: A. High serum phosphate B. High PTH C. High alkaline phosphatase D. Low serum calcium

A. High serum phosphate

Which of the following is the primary mechanism of compensation for metabolic acidosis? A. Hyperventilation B. Aldosterone release C. Release of epinephrine D. Bicarbonate excretion

A. Hyperventilation

Which condition produces the highest elevation of serum lactate dehydrogenase? A. Pernicious anemia B. Myocardial infarction C. Acute hepatitis D. Muscular dystrophy

A. Pernicious anemia

A compound that may be detected by observing its rose-red color in the aqueous layer of the Watson-Schwartz test is: A. Porphobilinogen B. Uroporphyrinogen C. Delta-aminolevulinic acid D. Coproporphyrin E. Urobilinogen

A. Porphobilinogen

Match the term with the corresponding description: A. Parathyroid hormone B. Oxytocin C. Thyroxine D. Growth hormone E. FSH F. Triiodothyronine G. Calcitonin H. ACTH I. LH J. Aldosterone K. TSH L. ADH

A. Regulation of calcium and phosphorus B. Uterine concentration during child birth C. Principle thyroid hormone responsible for metabolism, growth and development D. Protein synthesis, cell growth and division E. Sperm and egg production F. Mostly formed from the deiodination of t4, responsible for metabolism, growth and development G. Inhibition of calcium reabsorption H. Production of adrenocortical hormones by adrenal cortex I. Maturation of follicles, ovulation, production of estrogen, progesterone and testosterone J. Reabsorption of sodium in the renal tubules K. Production of T3 and T4 by thryoid L. Reabsorption of water in distal renal tubules

Which of the following conditions is associated with hypophosphatemia? A. Rickets B. Multiple myeloma C. Renal failure D. Hypervitaminosis D

A. Rickets

Which electrolyte level best correlates with plasma osmolality? A. Sodium B. Chloride C. Bicarbonate D. Calcium

A. Sodium

Which technique is used to detect DNA containing a specific base sequence by applying a labeled probe to DNA bands immobilized onto nitrocellulose paper following electrophoresis? A. Southern blot B. Northern blot C. Dot blot D. Western blot

A. Southern blot

A test's "negativity in the absence of the disease" is termed its: A. Specificity B. Predictive value C. Accuracy D. Sensitivity E. Efficiency

A. Specificity

True or false? Chloride is the major extracellular anion in plasma. A. True B. False

A. True

Upon receiving an arterial specimen for blood gases in the laboratory, you observe that it was not maintained under strict anaerobic conditions. You refuse to analyze the specimen. You base your decision on the premise that the following parameters have been altered: A. pH increased, pCO2 decreased, pO2 increased B. pH decreased, pCO2 increased, pO2 decreased C. pH increased, pCO2 increased, pO2 decreased D. pH decreased, pCO2 decreased, pO2 increased

A. pH increased, pCO2 decreased, pO2 increased

A low-salt diet, low blood pressure, and diuretics would cause the following results: A. Increased renin, increased aldosterone, hypernatremia, Hypokalemia B. Increased renin, decreased aldosterone, hypernatremia, Hypokalemia C. Decreased renin, decreased aldosterone, hyponatremia, Hyperkalemia D. Decreased renin, increased aldosterone, hyponatremia, Hyperkalemia

A.Increased renin, increased aldosterone, hypernatremia, Hypokalemia

Tubes that contain a gel serum separator should not be used for: A. Cholesterol testing B. Progesterone testing C. Pediatric patients D. VDRL testing

B - Progesterone testing

The coefficient of variation (CV) is: A. The square root of the standard deviation B. Standard deviation expressed as % of the average of the values used to calculate the standard deviation C. Standard deviation expressed as % of the range of values used to calculate the standard deviation D. Standard deviation expressed as % of the correlation coefficient E. Summation of duplicate differences expressed as % of the mean

B - Standard deviation expressed as % of the average of the values used to calculate the standard deviation

The greatest tissue source of CK is: A. Heart muscle B. Skeletal muscle C. Brain D. Thyroid

B - skeletal muscle

How many milliliters of 0.5N NaOH are required to make 100 milliliters of 0.2N NaOH? Selected Answer: B. 40 A. 250 B. 40 C. 25 D. 4

B. 40 Calculation: C1 x V1 = C2 x V2

What is the percentage of serum calcium that is ionized (Ca1)? A. 30% B. 45% C. 60% D. 80%

B. 45%

If the standard deviation is 4mg/dl and the mean is 100 with a +2SD what would should the control levels fall between? A. 96 and 104 B. 92 and 108 C. 88 and 112 D. Can't tell from the information

B. 92 and 108

Hypernatremia commonly occurs in: A. Burns, syndrome of inappropriate ADH, and excessive sweating without water intake B. Burns and excessive sweating without water intake C. Syndrome of inappropriate ADH and nephrotic syndrome D. Nephrotic syndrome only E. Burns, syndrome of inappropriate ADH, excessive sweating without water intake, and nephrotic syndrome

B. Burns and excessive sweating without water intake

Pituitary secretion of adrenocorticotropic hormone (ACTH) is inhibited by elevated levels of: A. Aldosterone B. Cortisol C. Estradiol-17b D. Progesterone E. Epinephrine

B. Cortisol

A plasma specimen from a hospital patient is analyzed on an osmometer and reported as 400 mOsm/Kg. What is the most likely effect on this patient's water distribution in the tissues? A. Edema B. Dehydration C. No change

B. Dehydration

When a purified enzyme is used as a reagent, such as urease in the measurement of urea, the enzyme must be ___________________ concentration so that the reaction follows_________________ kinetics. A. Limited; first B. Excess; first C. Limited; zero D. Excess; zero

B. Excess; first

True or false? The main function of antidiuretic hormone is to increase the reabsorption of sodium and increase the secretion of potassium. A. True B. False

B. False

Which of the following enzymes detects very early changes in liver cell damage? A. ALP B. GGT C. ALT D. Cholinesterase E. SGPT

B. GGT

The reference method for glucose determination is: A. Glucose dehydrogenase B. Hexokinase C. Glucose oxidase D. Copper reduction

B. Hexokinase

Blood specimens drawn early in the morning are recommended for measuring serum iron and TIBC because: A. Most people's diet is rich in iron B. Iron exhibits a diurnal cyclic variation C. Iron in serum goes into the cells after a meal D. The premise is incorrect; iron specimens do not need to be fasting

B. Iron exhibits a diurnal cyclic variation

Pituitary adenomas that secrete _______ are by far the most common form of hyperpituitarism. A. Growth hormone B. Prolactin C. ACTH D. TSH E. ADH

B. Prolactin

A chemistry analyzer that can perform multiple analyses on a single specimen during one run is referred to as a: A. Batch analyzer B. Random access analyzer C. Continuous-flow analyzer D. Chromatographic analyzer

B. Random access analyzer

The following laboratory results were obtained: Serum Electrolytes Arterial Blood Sodium 136 mEq/L pH 7.32 Potassium 4.4 mEq/L pCO2 79 mm Hg Chloride 92 mEq/L Bicarbonate 40 mEq/L These results are most compatible with: A. Respiratory alkalosis B. Respiratory acidosis C. Metabolic alkalosis D. Metabolic acidosis

B. Respiratory acidosis

Which formula provides the best estimate of serum transferrin? A. Serum Fe/TIBC B. TIBC (µg/dL) x 0.70 = transferrin in mg/dL C. Percent iron saturation x TIBC (µg/dL)/1.2 + 0.06 mg/dL D. Serum Fe (µg/dL) x 1.25 = transferrin (µg/dL)

B. TIBC (µg/dL) x 0.70 = transferrin in mg/dL

The major fraction of organic iodine circulating in the blood is: A. Thyroglobulin B. Tetraiodothyronine C. Triiodothyronine D. Diiodotyrosine

B. Tetraiodothyronine

A two-year-old child with a decreased serum T4 is described as being somewhat dwarfed, stocky, and overweight and having coarse features. Of the following, the most informative additional laboratory test would be serum: A. Thyroxine-binding globulin (TBG) B. Thyroid-stimulating hormone (TSH) C. Triiodothyronine (T3) D. Cholesterol

B. Thyroid-stimulating hormone (TSH)

A toxic condition involving a very high serum level of urea and creatinine accompanied by failure of the three main functions of the renal system is referred to as: A. Acute glomerulonephritis B. Uremia C. Azotemia D. Acute renal failure

B. Uremia

Which of the following forms of the HendersonHasselbalch equation is (are) correct? A. pH = 6.1 + log HCO3/H2CO3, pH = 6.1 + S x pCO2/HCO3, and pH = pKa + log HCO3/H2CO3 B. pH = 6.1 + log HCO3/H2CO3 and pH = pKa + log HCO3/H2CO3 C. ph = 6.1 + S x pCO2/HCO3 and pH = pKa - log HCO3/H2CO3 D. pH = pKa - log HCO3/H2CO3

B. pH = 6.1 + log HCO3/H2CO3 and pH = pKa + log HCO3/H2CO3

In a spectrophotometric determination, which one of the following is the formula for calculating the absorbance of a solution? A. (Absorptivity x concentration) / light path in cm B. (Absorptivity x light path in cm) / concentration C. Absorptivity x light path in cm x concentration D. (Light path in cm x concentration) / absorptivity

C - Absorptivity x light path in cm x concentration

Which of the following diseases is characterized by primary hyperaldosteronism caused by adrenal adenoma, carcinoma, or hyperplasia? A. Cushing's disease B. Addison's disease C. Conn's disease D. Pheochromocytoma

C - Conn's disease

Diurnal variation is a term that refers to: A. Whether or not a patient is fasting B. Collection of urine specimens C. Time of day of specimen collection D. Whether a patient is resting or exercising

C - Time of day of specimen collection

What is the normal ration of bicarbonate to dissolved carbon dioxide in arterial blood? A. 1:10 B. 10:1 C. 20:1 D. 30:1

C. 20:1

A patient brought to the emergency room has the following laboratory results: Sodium = 140 mmol/L Glucose = 80 mg/dLBUN = 6.0 mg/dL Osmolality = 316 mOsm/Kg H2O The calculated osmolality on this patient using the Weisberg formula is: A. 186 B. 267 C. 286 D. 316

C. 286 Calculation: 1.86(Na)+Glu/18+BUN/2.8+9

The major non-glucose-reducing substance present in serum is: A. Urea B. Protein C. Ascorbic acid D. Glutathione E. Cholesterol

C. Ascorbic acid

Factors used in determining whether POCT should be used include all of the following EXCEPT: A. Need B. Efficiency C. Benefit to the laboratory D. Cost

C. Benefit to the laboratory

Random-access analysis is a type of analysis in which a specimen: Selected Answer: C. A. Can be analyzed only in continuous sequence with other specimens B. Is subjected to a single process that produces results for a single analyte C. Can be analyzed by any available process without regard to the initial order of specimens D. Can be analyzed by any available process but only in the initial order of specimens

C. Can be analyzed by any available process without regard to the initial order of specimens

Which of the following is likely to occur first in iron deficiency anemia? A. Decreased serum iron B. Increased TIBC C. Decreased serum ferritin D. Increased transferrin

C. Decreased serum ferritin

The Jaffe alkaline picrate reaction for creatinine can be made more specific for creatinine with the use of: A. Urease B. Creatinine amidohydrolase C. Lloyd's reagent D. Sodium carbonate

C. Lloyd's reagent

A patient presents with Addison's disease. Serum sodium and potassium analyses are done. The results would reveal: A. Normal sodium, low potassium levels B. Low sodium, low potassium levels C. Low sodium, high potassium levels D. High sodium, low potassium levels

C. Low sodium, high potassium levels

The term below that is related to the ability of plasma proteins to maintain plasma water volume is: A. Isotonic equilibrium B. Crystalloid osmotic pressure C. Oncotic pressure D. Hydrostatic pressure

C. Oncotic pressure

The TRH (thyrotropin releasing hormone) stimulation test is useful in differentiating hypothalamic hypothyroidism from: A.Primary hypothyroidism B. Hashimoto's thyroiditis C. Pituitary hypothyroidism D. Sub-clinical hypothyroidism

C. Pituitary hypothyroidism

Interpret the following results on a young female that is complaining of extreme fatigue and weight gain. T4- Decreased T3-Decreased FT4-Decreased TSH-Decreased A. Hyperthyroidism B. Primary Hypothyroidism C. Secondary Hypothyroidism D. Normal

C. Secondary Hypothyroidism

What is the coefficient of variation formula?

CV = SD/mean x 100 Will be in percent form

How many millimoles of NaCl are contained in 300 mL of a 4M solution? (mw = 58.5) A. 70 B. 120 C. 234 D. 1200

D - 1200 Calculation: Mole = M x L 4 x 300

A patient sample for uric acid gave an absorbance reading of 0.4; the 50 mg/dL standard used in the test gave an absorbance reading of 0.1. What is the concentration of uric acid in the patient's sample in grams per deciliter? A. 0.2 B. 12.5 C. 125 D. 200

D - 200 Calculation: Abs of unk/abs of std x conc of std 0.4/0.1 x 50

In absorption spectrophotometry: A. Absorbance is directly proportional to transmittance B. Percent transmittance is directly proportional to concentration C. Percent transmittance is directly proportional to the light path length D. Absorbance is directly proportional to concentration

D - Absorbance is directly proportional to concentration

Violation of the 2-2S, 4-1S or 10x Westgard rules is a strong indication of _________. A. trend B. shift C. random error D. systematic error

D - systematic error

A solution contains 4.5 grams of BaCl2 in 400 mL. What is the normality? (mw = 208) A. 1.1 B. 0.05 C. 0.5 D. 0.11

D. 0.11 Calculation: N = M x V

Which of the following conditions is associated with hypokalemia? A. Addison's disease B. Hemolytic anemia C. Digoxin intoxication D. Alkalosis

D. Alkalosis

The parent substance in the biosynthesis of androgens and estrogens is: A. Cortisol B. Catecholamines C. Progesterone D. Cholesterol

D. Cholesterol

Peptide bonds of proteins bind with _________ ions of biuret reagent to produce a colored product. A. Ferrous B. Cuprous C. Ferric D. Cupric

D. Cupric

The formation of glucose from compounds like fatty acids, glycerol, and amino acids is called: A. Glycolysis B. Glycogenesis C. Glycogenolysis D. Gluconeogenesis

D. Gluconeogenesis

Which of the following is a tropic (stimulating) hormone? A. Thyroxine B. Testosterone C. Parathyroid hormone D. Growth hormone

D. Growth hormone

In a patient with suspected primary hyperthyroidism associated with Graves' disease, one would expect the following laboratory serum results: T4 _________, TSH _________. A. Increased, increased B. Decreased, normal C. Increased, normal D. Increased, decreased E. Normal, increased

D. Increased, decreased

What is the gold standard methodology for Toxicology testing? A. Immunoassay B. Electrophoresis C. Liquid Chromatography D. Mass Spectrometry

D. Mass Spectrometry

H2CO3 is regulated by the lungs and is equal to: A. PCO2 X 3.00 B. PCO2 X 0.03 C. HCO3 X 0.33 D. PCO2 X 0.03

D. PCO2 X 0.03

Progesterone: A. Is produced in adult testes and is responsible for genital development, beard growth, muscle development, and sexual drive B. Is produced by the placenta during pregnancy, with highest levels seen at conception and then steadily decreasing to non-detectable levels at term C. Is lowest is serum during the luteal phase of the menstrual cycle and highest during the follicular phase D. Parallels activity of the corpus luteum by rapidly increasing following ovulation and then abruptly falling to initial low concentrations prior to the onset of menstruation

D. Parallels activity of the corpus luteum by rapidly increasing following ovulation and then abruptly falling to initial low concentrations prior to the onset of menstruation

Which of the following conditions will cause an increased anion gap? A. Diarrhea B. Hypoaldosteronism C. Hyperkalemia D. Renal failure

D. Renal failure

A low plasma osmolality and low sodium would be expected in a patient with: A. Dehydration B. Diabetes mellitus C. Diabetes insipidus D. SIADH

D. SIADH

The FINAL metabolite of epinephrine that is measured in urine is: A. Dopamine B. Metanephrines C. Homovanillic acid D. Vanillylmandelic acid

D. Vanillylmandelic acid

The acute phase reactant protein that also inhibits proteolysis and has the highest concentration within its globulin fraction is: A. C-reactive protein B. Haptoglobin C. Alpha2-macroglobulin D. Alpha1-antichymotrypsin E. Alpha1-antitrypsin

E. Alpha1-antitrypsin

Which of the following is an effect of increased parathyroid hormone secretion? A. Decreased blood calcium levels B. Increased renal reabsorption of phosphate C. Decreased bone resorption D. Increased intestinal absorption of calcium E. Decreased blood calcium levels, increased renal reabsorption of phosphate, decreased bone resorption, and increased intestinal absorption of calcium

E. Decreased blood calcium levels, increased renal reabsorption of phosphate, decreased bone resorption, and increased intestinal absorption of calcium

Which of the following enzymes has multiple molecular forms (isoenzymes) whose clinical significance is used in diagnosis? A. Lactate dehydrogenase B. Creatinine kinase C. Alkaline phosphatase D. Lactate dehydrogenase and creatinine kinase only E. Lactate dehydrogenase, creatinine kinase, and alkaline phosphatase

E. Lactate dehydrogenase, creatinine kinase, and alkaline phosphatase

True or false? Serum urea levels are less affected by diet and metabolism than are serum creatinine levels.

False