Download Clinical Chemistry Exam Prep: Blood Glucose and Acid-Base Balance Q&A and more Exams Hematology in PDF only on Docsity!
Complete BOC: ASCP prep questions
and answers with verified solutions
- Following overnight fasting, hypoglycemia in adults is defined as a glucose of: a. <70 mg/dL (<3.9 mmol/L) b. <60 mg/dL (<3.3mmol/L) c. <55 mg/dL (<3.0mmol/L)
d. <45mg/dL (<2.5mmol/L) ✔✔d (Diagnosis of hypoglycemia in adults.)
- The preparation of a patient for standard glucose tolerance testing should include: a. a high carbohydrate diet for 3 days b. a low carbohydrate diet for 3 days c. fasting for 48 hrs. prior to testing
d. bed rest for 3 days ✔✔a (GTT diet preparation.)
- If a fasting glucose was 90 mg/dL, which of the following 2 hr. postprandial glucose result would most closely represent normal glucose metabolism? a. 55 mg/dL (3.0 mmol/L) b. 100 mg/dL (5.5 mmol/L) c. 180 mg/dL (9.9 mmol/L)
d. 260 mg/dL (14.3 mmol/L) ✔✔b (Normal 2 hour postprandial value.)
- A healthy person with a blood glucose of 80 mg/dL (4.4 mmol/L) would have a simultaneously determined cerebrospinal fluid glucose value of: a. 25 mg/dL (1.4 mmol/L) b. 50 mg/dL (2.3 mmol/L) c. 100 mg/dL (5.5 mmol/L)
d. 150 mg/dL (8.3 mmol/L) ✔✔b (Ratio of CSF glucose to blood glucose)
- A 25 yr. old man became nauseated and vomited 90 mins after receiving a standard 75 g carbohydrate dose for an oral glucose tolerance test. The best course of action is to: a. give the patient a glass of orange juice and continue the test b. start the test over immediately with a 50 g carbohydrate dose c. draw blood for glucose and discontinue the test d. place the patient in a recumbent position, reassure him and continue the test. ✔✔c (Use of
partial GTT information.)
- Cerebrospinal fluid for glucose assay should be: a. refrigerated b. analyzed immediately c. heated to 56C
d. stored at room temperature after centrifugation ✔✔b (Effect of glycolysis on glucose.)
- Which of the following 2 hr. postprandial glucose values demonstrates unequivocal hyperglycemia diagnostic for diabetes mellitus?
c. epinephrine tolerance test d. glucose tolerance test ✔✔d (Gestational diabetes.)
- In the fasting state, the arterial and capillary blood glucose concentration varies from the venous glucose concentration by approximately how many mg/dL (mmol/L) a. 1 mg/dL (0.05 mmol/L) b. 5 mg/dL (0.27 mmol/L) c. 10 mg/dL (0.55 mmol/L)
d. 15 mg/dL (0.82 mmol/L) ✔✔b (Arterial vs venous glucose values.)
- The conversion of glucose or other hexoses into lactate or pyruvate is called: a. glycogenesis b. glycogenolysis c. gluconeogenesis
d. glycolysis ✔✔d (Definition of glycolysis)
- Which of the following values obtained during a glucose tolerance test are diagnostic of diabetes mellitus? a. 2 hr. specimen = 150 mg/dL (8.3 mmol/L) b. fasting plasma glucose = 126 mg/dL (6.9 mmol/L) c. fasting plasma glucose = 110 mg/dL (6.1 mmol/L) d. 2 hr. specimen = 180 mg/dL (9.9 mmol/L) ✔✔b (Diagnosis of diabetes mellitus)
- The glycated hemoglobin value represents the integrated values of glucose concentration during the preceding: a. 1-3 weeks b. 4-5 weeks c. 6-8 weeks
d. 16-20 weeks ✔✔c (Definition of glycated hemoglobin.)
Monitoring long term glucose control in patients with adult onset diabetes mellitus can best be accomplished by measuring: a. weekly fasting 7 am serum glucose b. glucose tolerance testing c. 2 hr. postprandial serum glucose d. hemoglobin A1c ✔✔d (Average glucose over time is best predictor.)
Total glycosylated hemoglobin levels in a hemolysate reflect the: a. average blood glucose levels of the past 2-3 months b. average blood glucose levels for the past week c. blood glucose level at the time the sample is drawn d. hemoglobin A1c level at the time the sample is drawn ✔✔a (Interpretation of glycated
hemoglobin.)
- Which of the following hemoglobins has glucose-6-phosphate on the amino-terminal valine of the beta chain?
- An infant with diarrhea is being evaluated for a carbohydrate intolerance. His stool yields a positive copper reduction test and a pH of 5.0. It should be concluded that: a. further tests are indicated b. results are inconsistent-repeat both tests c. the diarrhea is not due to carbohydrate intolerance d. the tests provided no useful information ✔✔a (Copper reduction reaction detects many
reducing substances.)
- Blood samples were collected at the beginning of an exercise class and after thirty mins. of aerobic activity. Which of the following would be most consistent with the post exercise sample? a. normal lactic acid, low pyruvate b. low lactic acid, elevated pyruvate c. elevated lactic acid, low pyruvate
d. elevate lactic acid, elevated pyruvate ✔✔d (Products of glycolysis.)
- What is the best method to diagnose lactase deficiency? a. H2 breath test b. plasma aldolase level c. LDH level
d. d-xylose test ✔✔a (Diagnosis of lactase deficiency.)
- The expected blood gas results for a patient in chronic renal failure would match the pattern of: a. metabolic acidosis b. respiratory acidosis c. metabolic alkalosis
d. respiratory alkalosis ✔✔a (Reduced excretion of acids.)
- Severe diarrhea causes: a. metabolic acidosis b. metabolic alkalosis c. respiratory acidosis
d. respiratory alkalosis ✔✔a (Excessive loss of bicarbonate.)
Factors that contribute to a PCO2 electrode requiring 60-120 seconds to reach equilibrium include the: a. diffusion characteristics of the membrane b. actual blood PO c. type of calibrating standard d. potential of the polarizing mercury cell ✔✔a (Blood gas instrumentation.)
An emphysema patient suffering from fluid accumulation in the alveolar spaces is likely to be in what metabolic state? a. respiratory acidosis
A patient is admitted to the emergency room in a state of metabolic alkalosis. Which of the following would be consistent with this diagnosis? a. high PCO2, increased HCO b. low PCO2, increased HCO c. high PCO2, decreased HCO d. low PCO2, decreased HCO3 ✔✔a (HCO3 and TCO2 in metabolic alkalosis.)
A person suspected of having metabolic alkalosis would have which of the following laboratory findings? a. CO2 content elevated and PCO2 elevated, pH decreased b. CO2 content decreased and pH elevated c. CO2 content decreased, PCO2 decreased and pH decreased
d. CO2 content elevated and pH elevated ✔✔d (Levels of CO2 and pH in metabolic alkalosis.)
- Metabolic acidosis is described as a: a. increase in CO2 content and PCO2 with a decrease pH b. decrease in CO2 content with an increased pH c. increase in CO2 with an increased pH
d. decrease in CO2 content and PCO2 with a decreased pH ✔✔d (Component levels in metabolic
acidosis.)
- A common cause of respiratory alkalosis is:
a. vomiting b. starvation c. asthma
d. hyperventilation ✔✔d (Respiratory alkalosis caused by hyperventilation)
Acidosis and alkalosis are best defined as fluctuations in blood pH and CO2 content due to changes in: a. Bohr effect b. O2 content c. bicarbonate buffer d. carbonic anhydrase ✔✔c (Chemical cause of alkalosis and acidosis.)
A blood gas sample was sent to the lab on ice, and a bubble was present in the syringe. The blood had been exposed to room air for at least 30 mins. The following change in blood gases will occur: a. CO2 content increased/PCO2 decreased b. CO2 content and PO2 increased/pH increased c. CO2 content and PCO2 decreased/pH decreased d. PO2 increased/HCO3 decreased ✔✔d (Blood gas sample conditions.)
Select the test which evaluates renal tubular function: a. IVP b. creatinine clearance
b. there is no lipoprotein interference c. of advances in electrochemistry
d. of the absence of an internal standard ✔✔c (Ion selective electrode standard Na K.)
- What battery of tests is most useful in evaluating an anion gap of 22 mEq/L (22 mmol/L)? a. Ca++, Mg++, PO-4, and pH b. BUN, creatinine, salicylate and methanol c. AST, ALT, LD and amylase
d. glucose, CK, myoglobin, and cryoglobulin ✔✔b (Components of anion gap.)
- Most of the carbon dioxide present in blood is in the form of: a. dissolved CO b. carbonate c. bicarbonate ion
d. carbonic acid ✔✔c (Major component of CO2 in blood.)
- Serum anion gap is increased in patients with: a. renal tubular acidosis b. diabetes alkalosis c. metabolic acidosis due to diarrhea
d. lactic acidosis ✔✔d (Anion gap, lactic acidosis.)
- The anion gap is useful for quality control of laboratory results for:
a. amino acids and proteins b. blood gas analyzers c. Na, K, Cl, and CO
d. Ca, Ph, Mg ✔✔c (Calculation of anion gap.)
The buffering capacity of blood is maintained by a reversible exchange process between bicarbonate and: a. sodium b. potassium c. calcium d. chloride ✔✔d (Maintenance of buffering capacity blood.)
In respiratory acidosis, a compensatory mechanism is the increase in: a. respiration rate b. ammonia formation c. blood PCO d. plasma bicarbonate concentration ✔✔d (Compensatory mechanism in respiratory acidosis.)
Which of the following electrolytes is the chief plasma cation whose main function is maintaining osmotic pressure? a. chloride b. calcium c. potassium
Which of the following is true about direct ion selective electrodes for electrolytes? 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 ✔✔a (Direct ISE method.)
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 ✔✔b (Interferences with indirect ISE methods.)
A physician requested that electrolytes on a multiple myeloma patient specimen be run by direct ISE and not indirect ISE because: a. excess protein binds Na in indirect ISE b. Na falsely increased by indirect ISE c. Na is falsely decreased by indirect ISE
d. excess protein reacts with diluent in indirect ISE ✔✔c (Interferences with indirect ISE
methods.)
- Which percentage of total serum calcium is nondiffusible protein bound? a. 80% - 90% b. 51% - 60%
c. 40% - 50% d. 10% - 30 % ✔✔c (Protein-bound Ca++.)
Calcium concentration in the serum is regulated by: a. insulin b. parathyroid hormone c. thyroxine d. vitamin C ✔✔b (Regulation of Ca++.)
The regulation of calcium and phosphorous metabolism is accomplished by which of the following glands? a. thyroid b. parathyroid c. adrenal gland
d. pituitary ✔✔b (Regulation of Ca++ and P043- metabolism.)
- A patient has the following results: increased serum calcium decreased serum phosphate increased levels of parathyroid hormone: This patient most likely has: a. hyperparathyroidism b. hypoparathyroidism
Fasting serum phosphate concentration is controlled primarily by the: a. pancreas b. skeleton c. parathyroid glands d. small intestine ✔✔c (Regulation of phosphate.)
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 ✔✔a (Most common cause of low phosphate.)
The primary function of 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 ✔✔a (Physiological feature of albumin.)
The first step in analyzing a 24 hr. 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 ✔✔d (Basic principle of lab procedure timed urine.)
- The following data was obtained from a cellulose acetate protein electrophoresis scan: albumin area = 75 units gamma globulin area = 30 units total area = 180 units total protein = 6.4 g/dL (65 g/L) The gamma globulin content in g/dL is: a. 1.1 g/dL (11 g/L) b. 2.7 g/dL (27 g/L) c. 3.8 g/dL (38 g/L)
d. 4.9 g/dL (49 g/L) ✔✔a (A ratio and proportion procedure is most useful for calculations in
which concentrations are not changed, as in this case. Set up a ratio of total area [18] to gamma globulin area [30] in units, and total protein content [6.5] to gamma globulin content [x] in g/dL. Solve for x.)
- Total iron binding capacity measures the serum iron transporting capacity of: a. hemoglobin b. ceruloplasmin c. transferrin
d. ferritin ✔✔c (Transport function of transferrin.)
- The first step in the quantitation of serum iron is: a. direct reaction with appropriate chromogen
