Quiz Answers
- Osmolal gap is a difference between:
- a. The ideal and real osmolality values
- b. Calculated and measured osmolality values ✅
- c. Plasma and water osmolality values
- d. Molality and molarity at 4 degrees Celsius
- The most important buffer pair in plasma is the
- a. Phosphate/biphosphate pair
- b. Hemoglobin/imidazole pair
- c. Bicarbonate/carbonic acid pair ✅
- d. Sulfate/bisulfate pair
- Quantitation of Na+ and K+ by ion-selective electrode is the standard method because:
- a. Dilution is required for flame photometry
- b. There is no lipoprotein interference
- c. Of advances in electrochemistry ✅
- d. Of the absence of an internal standard
- Most of the carbon dioxide present in blood in the form of:
- a. Dissolved CO^2
- b. Carbonate
- c. Bicarbonate ion ✅
- d. Carbonic acid
- Serum “anion gap” is increased in patients with:
- a. Renal tubular acidosis
- b. Diabetic alkalosis
- c. Metabolic acidosis due to diarrhea
- d. Lactic acidosis ✅
- The anion gap is useful for quality control of laboratory results for:
- a. Amino acids and proteins
- b. Blood gas analyses
- c. Sodium, potassium, chloride, and total CO2 ✅
- d. Calcium, phosphorus, and magnesium
- The buffering capacity of blood is maintained by a reversible exchange process between bicarbonate and:
- a. Sodium
- b. Potassium
- c. Calcium
- d. Chloride ✅
- In respiratory acidosis, a compensatory mechanism is the increase in:
- a. Respiratory rate
- b. Ammonia formation
- c. Blood PCO2
- d. Plasma bicarbonate concentration ✅
- Which of the following electrolytes is the chief plasma cation whose main function is maintaining osmotic pressure?
- a. Chloride
- b. Calcium
- c. Potassium
- d. Sodium ✅
- The solute that contributes the most to the total serum osmolality is:
- a. Glucose
- b. Sodium ✅
- c. Chloride
- d. Urea
- Which of the following is true about direct ion selective electrode is falsely decreased by:
- a. Whole blood specimens are acceptable ✅
- b. Elevated lipids cause falsely decreased results
- c. Elevated proteins cause falsely decreased results
- d. Elevated platelets cause falsely increased results
- Sodium determination by indirect ion selective electrode is falsely decreased by:
- a. Elevated chloride levels
- b. Elevated lipid levels ✅
- c. Decreased protein levels
- d. Decreased albumin levels
- Which percentage of total serum calcium is nondiffusible protein bound?
- a. 80%-90%
- b. 51%-60%
- c. 40%-50% ✅
- d. 10%-30%
- Calcium concentration in the serum is regulated by:
- a. Insulin
- b. Parathyroid hormone ✅
- c. Thyroxine
- d. Vitamin C
- The regulation of calcium and phosphorus metabolism is accomplished by which of the following glands?
- a. Thyroid
- b. Parathyroid ✅
- c. Adrenal glands
- d. Pituitary
- A hospitalized patient is experiencing increased neuromuscular irritability (tetany). Which of the following tests should be ordered immediately?
- a. Calcium ✅
- b. Phosphate
- c. BUN
- d. Glucose
- Which is the following is most likely to be ordered in addition to serum calcium to determine the cause of tetany?
- a. Magnesium ✅
- b. Phosphate
- c. Sodium
- d. Vitamin
- A reciprocal relationship exists between:
- a. Sodium and potassium
- b. Calcium and phosphate ✅
- c. Chloride and CO2
- d. Calcium and magnesium
- Fasting serum phosphate concentration is controlled primarily by the:
- a. Pancreas
- b. Skeleton
- c. Parathyroid glands ✅
- d. Small intestine
- A low concentration of serum phosphorus is commonly found in:
- a. Patients who are receiving carbohydrate hyperalimentation ✅
- b. Chronic renal disease
- c. Hypoparathyroidism
- d. Patients with pituitary tumors
- The primary function serum albumin in the peripheral blood is to:
- a. Maintain colloidal osmotic pressure ✅
- b. Increase antibody production
- c. Increase fibrinogen formation
- d. Maintain blood viscosity
- The first step in analyzing a 24-hour urine specimen for quantitative urine protein is:
- a. Subculture the urine for bacteria
- b. Add the appropriate preservative
- c. Screen for albumin using a dipstick
- d. Measure the total volume ✅
- Total iron-binding capacity measures the serum iron transporting capacity of:
- a. Hemoglobin
- b. Ceruloplasmin
- c. Transferrin ✅
- d. Ferritin
- The first step in the quantitation of serum iron is:
- a. Direct reaction with appropriate chromagen
- b. Iron saturation of transferrin
- c. Free iron precipitation
- d. Separation of iron from transferrin ✅
- A serum sample demonstrates an elevated result when tested with the Jaffe reaction. This indicates:
- a. Prolonged hypothermia
- b. Renal functional impairment ✅
- c. Pregnancy
- d. Arrhythmia
- Creatinine clearance is used to estimate the:
- a. Tubular secretion of creatinine
- b. Glomerular secretion of creatinine
- c. Renal glomerular and tubular mass
- d. Glomerular filtration rate ✅
- 90% of the copper present in the blood is bound to:
- a. Transferrin
- b. Ceruloplasmin ✅
- c. Albumin
- d. Cryoglobulin
- Hemoglobin S can be separated from hemoglobin D by:
- a. Electrophoresis on a different medium and acidic pH ✅
- b. Hemoglobin A2 quantitation
- c. Electrophoresis at higher voltage
- d. Kleihauer-Betke acid elution
- On electrophoresis at alkaline pH, which of the following is the slowest migrating hemoglobin?
- a. Hgb A
- b. Hgb S
- c. Hgb C ✅
- d. Hgb F
- Urobilinogen is formed in the:
- a. Kidney
- b. Spleen
- c. Liver
- d. Intestine ✅
- Kernicterus is an abnormal accumulation of bilirubin in:
- a. Heart tissue
- b. Brain tissue ✅
- c. Liver tissue
- d. Kidney tissue
- A stool specimen that appears black and tarry should be tested for the presence of:
- a. Occult blood ✅
- b. Fecal fat
- c. Trypsin
- d. Excess mucus
- The most specific enzyme test for acute pancreatitis is:
- a. Acid phosphatase
- b. Trypsin
- c. Amylase
- d. Lipase ✅
- Which of the following enzymes are used in the diagnosis of acute pancreatitis?
- a. Amylase (AMS) and lipase (LPS) ✅
- b. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT)
- c. 5′ -nucleotidase (5’N) and gamma-glutamyl transferase (GGT)
- d. Aspartate aminotransferase (AST) and lactate dehydrogenase(LD)
- Which of the following enzymes catalyzes the conversion of starch to glucose and maltose?
- a. Malate dehydrogenase (MD)
- b. Amylase (AMS) ✅
- c. Creatine kinase (CK)
- d. Isocitric dehydrogenase (ICD)
- Aspartate amino transferase (AST) is characteristically elevated in diseases of the:
- a. Liver ✅
- b. Kidney
- c. Intestine
- d. Pancreas
- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are both elevated in which of the following diseases?
- a. Muscular dystrophy
- b. Viral hepatitis ✅
- c. Pulmonary emboli
- d. Infectious mononucleosis
- The greatest activities of serum AST and ALT are seen in which of the following?
- a. Acute viral hepatitis
- b. Primary biliary cirrhosis ✅
- c. Metastatic hepatic cirrhosis
- d. Alcoholic cirrhosis
- 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 ✅
- The enzyme present in almost all tissues that may be separated by electrophoresis into 5 components is:
- a. Lipase
- b. Transaminase
- c. Creatine kinase
- d. Lactate dehydrogenase ✅
- A common cause of falsely increased LD1 fraction of lactic dehydrogenase is:
- a. Specimen hemolysis ✅
- b. Liver disease
- c. Congestive heart failure
- d. Drug toxicity
- The presence of which of the following isoenzymes indicates acute myocardial damage?
- a. CKMM
- b. CKMB ✅
- c. CKBB
- d. None
- In which of the following conditions would a normal level of creatine kinase be found?
- a. Acute myocardial infarct
- b. Hepatitis ✅
- c. Progressive muscular dystrophy
- d. Intramuscular injection
- Of the following diseases, the one most often associated with elevations of lactate dehydrogenase isoenzymes 4 and 5 on electrophoresis is:
- a. Liver disease ✅
- b. Hemolytic anemia
- c. Myocardial infarction
- d. Pulmonary edema
- When myocardial infarction occurs, the first enzyme to become elevated is:
- a. CK ✅
- b. LD
- c. AST
- d. ALT
- In the immunoinhibition phase of the CKMB procedure:
- a. M subunit is inactivated ✅
- b. B subunit is inactivated
- c. MB is inactivated
- d. BB is inactivated
- The presence of increased CKMB activity on a CK electrophoresis pattern is most likely found in a patient suffering from:
- a. Acute muscular stress following strenuous exercise
- b. Malignant liver disease
- c. Myocardial infarction ✅
- d. Severe head injury
- Increased serum lactic dehydrogenase activity due to elevation of fast fraction (1 and 2) on electrophoretic separation is caused by:
- a. Nephrotic syndrome
- b. Hemolytic anemia ✅
- c. Pancreatitis
- d. Hepatic damage
- Regan isoenzyme has the same properties as alkaline phosphatase that originates in the:
- a. Skeleton
- b. Kidney
- c. Intestine
- d. Placenta ✅
- The most heat labile fraction of alkaline phosphatase is obtained from:
- a. Liver
- b. Bone ✅
- c. Intestine
- d. Placenta
