Chemistry Rotation Exam

A 1 year old girl with hyperlipoproteinemia and lipase deficiency has the following lipid profile -

Cholesterol 300 mg/dL

LDL increased

HDL decreased

Triglycerides 200 mg/dL

Chylomicrons present

A serum specimen from this patient that was refrigerated overnight would most likely be -

A. Clear

B. Cloudy

C. Creamy layer over cloudy serum

D. Creamy layer over clear serum

D

Most chemical methods for determining total protein utilize which of the following reactions?

A. Ferri-ferrocyanide

B. Biuret

C. Resocinol-HC1

D. Molybdenum blue

B

The buffering capacity of blood is maintained by a reversible exchange process between bicarbonate and -

A. Chloride

B. Sodium

C. Potassium

D. Calcium

A

Which of the following sample collections would give an accurate assessment of potential excess cortisol production?

A. Collect a plasma at baseline and another one hour after administration of metro-one

B. Collect a 24 hour urine free cortisol

C. Collect a plasma sample at 8am only

D. Collect a plasma sample at 8am and 8am the next day

B

In electrophoresis of proteins, when the sample is placed in an electric field connected to a buffer of pH 8.6, all of the proteins -

A. Have a positive charge

B. Have a negative charge

C. Migrate towards the cathode

D. Are electrically neutral

B

In the Jaffe reaction, creatinine reacts with -

A. Alkaline picrate solution to yield an orange red complex

B. Sodium nitroferricyanide to yield a reddish brown color

C. Potassium iodide to form a reddish purple complex

D. Alkaline sulfosalazine solution to produce an orange yellow complex

A

Which of the following lipid results would be expected to be falsely elevated on a serum specimen from a non fasting patient?

A. Cholesterol

B. HDL

C. Triglyceride

D. LDL

C

Which of the following factors is not relevant to therapeutic drug monitoring of the ahminoglycosides, antibiotics and vancomycin?

A. Intestinal absorption

B. Oxotoxicity

C. Nephrotoxicity

D. Renal function

A

When myocardial infarction occurs, the first enzyme to become elevated is -

A. AST

B. LD

C. CK

D. ALT

C

The urinary excretion product measured as an indicator of epinephrine production is -

A. Vanillylmandelic acid

B. Homovanillic acid

C. Dopamine

D. Dihydroxyphenylalanine (DOPA)

A

Which of the following clinical disorders is associated with the greatest elevation of lactate dehydrogenase isoenzyme 1?

A. Pneumonia

B. Glomerulonephritis

C. Pancreatitis

D. Pernicious anemia

D

Osmolal gap is the difference between -

A. Molality and molarity at 4 degrees C

B. The ideal and real osmolality values

C. Plasma and water osmolality values

D. Calculated and measured osmolality values

D

The troponin complex consists of -

A. Troponin I, actin, and tropomyosin

B. Troponin C, myoglobin, and actin

C. Troponin T, calcium, and tropomyosin

D. Troponin C, troponin I, and troponin T

D

A 9 month old boy from Israel has gradually lost the ability to sit up and develop seizures. He has an increased amount of a phospholipid called GM2-ganglioside in his neurons, and he lacks the enzyme hexosaminidase A in his leukocytes. These findings suggest -

A. Neimann-Pick disease

B. Phenylketonuria

C. Tay-Sachs disease

D. Hurlers syndrome

C

Which blood gas electrode is composed of silver/silver chloride reference electrode and glass?

A. pH

B. PCO2

C. HCO3

D. PO2

B

Which of the following applies to cryoscopic osmometry?

A. The freezing point of a sample is absolute

B. The temperature plateau for a solution is horizontal

C. The initial freezing of sample produces an immediate solid state

D. The temp at equilibrium is a function of the number of particles in solution

D

The enzyme that exists chiefly in skeletal muscle, heart and brain; is grossly elevated in active muscular dystrophy; and rises in myocardial infarction is -

A. Lactate dehydrogenase

B. Creatine kinase

C. Transaminase

D. Lipase

B

A physical requested that electrolytes on a multiple myeloma patient specimen be run by direct ISE and not indirect ISE because -

A. Excess protein reacts with diluent in indirect ISE

B. Na is falsely increased by indirect ISE

C. Excess proteins binds Na in indirect ISE

D. Na is falsely decreased by indirect ISE

D

The first step in the quantitation of serum iron is -

A. Iron saturation of transferrin

B. Free iron precipitation

C. Direct reaction with appropriate chromogen

D. Separation of iron from transferrin

D

Upon development of a thin layer chromatogram for drug analysis, all drug spots (including the standards) had migrated with the solvent front. The most probably cause for this would be -

A. Environmental temperature too warm

B. Too much sample applied

C. Chromatogram dried too quickly

D. Incorrect aqueous to non aqueous solvent mixture

D

Refer to the following -

Total protein - 8.5 (6-8)

Albumin - 4.3 (3.6-5.2)

Alpha-1 - 0.3 (0.1-0.4)

Alpha-2 - 0.7 (0.4-1)

Beta - 0.9 (0.5-1.2)

Gamma - 2.3 (0.6-1.6)

The above serum protein electrophoresis pattern is consistent with -

A. Alpha-1 antitrypsin deficiency, severe emphysema

B. Monoclonal gammopathy

C. Polyclonal gammopathy (IE - chronic inflammation)

D. Cirrhosis

C

Copy of most automated blood gas analyzers directly measure -

A. pH, PCO2, and PO2

B. pH, HCO3-, and % O2 saturation

C. HCO3-, PCO2, and PO2

D. pH, PO2, and % O2 saturation

A

The solute that contributes the most to the total serum osmolality is -

A. Urea

B. Sodium

C. Chloride

D. Glucose

B

Absorption of vitamin B12 requires the presence of -

A. Intrinsic factor

B. Folic acid

C. Gastrin

D. Secretin

A

In the Jendrassik-Grof reaction for total bilirubin, bilirubin reacts with diazotized sulfanilic acid to form -

A. Azobilirubin

B. Bilirubin glucuronide

C. Diazo bilirubin

D. Biliverdin

A

In using ion exchange chromatographic methods, falsely increased levels of HbA1C might be demonstrated in the presence of -

A. Thalassemias

B. Iron deficiency anemia

C. Hb S

D. Pernicious anemia

C

In addition to carcinoma of the prostate, elevated prostate specific antigen can occur due to -

A. Aspirin therapy

B. Exogenous steroid use

C. Statin therapy

D. Benign prostatic hyperplasia

D

In developing the reference for a new EIA for CEA, the range for the normal population was broader than that published to the vendor. Controls are acceptable with a narrow coefficient of variation. This may be explained by -

A. Improper temp control during assay

B. Inclusion of nonsmokers and smokers in the study population

C. Population skewed to a younger age

D. Positive interference by another tumor marker

B

Pregnant women with symptoms of thirst, frequent urination or unexplained weight loss should have which of the following tests performed?

A. Tolbutamide test

B. Lactose tolerance test

C. Glucose tolerance test

D. Epinephrine tolerance test

C

A serum sample demonstrates an elevated result when tested with the Jaffe reaction. This indicates -

A. Renal functional impairment

B. Arrythmia

C. Pregnancy

D. Prolonged hypothermia

A

A low concentration of serum phosphorous is commonly found in -

A. Hypoparathyroidism

B. Patients who are receiving carbohydrate hyperalimentation

C. Chronic renal disease

D. Patients with pituitary tumors

B

The urea nitrogen concentration of a serum sample was measured to be 15 mg/dL

Urea - NH2CONH2

Atomic weight - N = 14, C = 12, O = 16, H = 1

The urea concentration of the same sample in mg/dL is -

A. 15

B. 24

C. 32

D. 40

C

A patient with hemolytic anemia will -

A. Show an increase in glycated Hb b value

B. Show a decrease in glycated Hb b value

C. Demonstrates an elevated Hb b A1

D. Show little or no change in glycated Hb b value

B

An anti-epileptic used to control seizure disorders is -

A. Phenytoin

B. Acetominophen

C. Lithium

D. Digoxin

A

CA 125 is a tumor marker associated with -

A. Breast carcinoma

B. Colon cancer

C. Lung cancer

D. Ovarian and endometrial carcinoma

D

A patient with glomerulonephritis would present the following serum results -

A. Phosphorous decreased

B. Calcium increased

C. BUN increased

D. Creatinine decreased

C

What substance gives feces its normal color?

A. Uroerythrin

B. Urochrome

C. Urobilin

D. Urobilinogen

C

In a pleural effusion caused by Strep pneumoniae, the protein value of the pleural fluid compared with the serum value would probably be -

A. Equal

B. Decreased by 2

C. Decreased by one half

D. Increased by one half

C

If a fasting glucose was 90 mg/dL, which of the following 2 hour postprandial glucose results would most closely represent normal glucose metabolism?

A, 55 mg/dL

B. 180 mg/dL

C. 260 mg/dL

D. 100 mg/dL

D

During a normal pregnancy, quantitative HCG levels peak how many weeks after the last menstrual period?

A. 18-20

B. 14-16

C. 8-10

D. 2-4

C

Fasting serum phosphate concentration is controlled primarily by the -

A. Small intestine

B. Skeleton

C. Pancreas

D. Parathyroid glands

D

Amperometry is the principle of -

A. Ionized calcium electrode

B. PCO2 electrode

C. pH electrode

D. PO2 electrode

D

High levels of which lipoprotein class are associated with decreased risk of accelerated atherosclerosis?

A. VLDL

B. HDL

C. Chylomicrons

D. LDL

B

A person suspected of having metabolic alkalosis would have which of the following lab findings?

A. CO2 content and pH elevated

B. CO2 content and PCO2 elevated, pH decreased

C. CO2 content, PCO2, and pH decreased

D. CO2 content decreased and pH elevated

A

Reverse phase high performance liquid chromatography is being increasingly utilized in therapeutic drug monitoring. The term reverse phase implies that the column eluant is -

A. More polar than the stationary phase

B. Pumped up the column

C. Always nonpolar

D. Less polar than the stationary phase

A

A healthy person with a blood glucose of 80 mg/dL would have a simultaneously determined CSF glucose value of -

A. 50 mg/dL

B. 25 mg/dL

C. 100 mg/dL

D. 150 mg/dL

A

To ensure an accurate ammonia level result, the specimen should be -

A. Stored at room temp until tested

B. Spun, separated, iced, and tested immediately

C. Spun and separated immediately, tested as routine

D. Incubated at 37C prior to testing

B

Serum from a patient with metastatic carcinoma of the prostate was separated from the close and stored at room temp. The following results were obtained -

Ca - 10.8 mg/dL (8.8-10.3 mg/dL)

LD - 420 U/L (50-150 U/L)

Acid phosphatase - 0.1 U/L (0-5.5 U/L)

The tech should repeat the -

A. LD using diluted serum

B. LD with fresh serum

C. Tests using plasma

D. Acid phosphatase with freshly drawn serum

D

An automated method for measuring chloride that generates silver ions in the reaction is -

A. Chromatography

B. Coulometry

C. Polarography

D. Mass spectroscopy

B

Valinomycin enhances the selectivity of the electrode used to quantitate -

A. Chloride

B. Calcium

C. Potassium

D. Sodium

C