10 INTRODUCTION TO CLINICAL CHEMISTRY Flashcards
One of the major hormones that controls high glucose levels after a meal is:
a. Insulin
b. Thyroxine
c. Glucagon
d. Lipase
a. Insulin
In a person with normal glucose metabolism, the blood glucose level usually increases rapidly after carbohydrates are ingested but returns to a normal level after:
a. 30 minutes
b. 45 minutes
c. 60 minutes
d. 120 minutes
d. 120 minutes
Which of the following organs uses glucose from digested carbohydrates and stores it as glycogen for later use as a source of immediate energy by the muscles?
a. Kidneys
b. Liver
c. Pancreas
d. Thyroid
b. Liver
In a person with impaired glucose metabolism, such as in type 1 diabetes, what is true about the blood glucose level?
a. It increases rapidly after carbohydrates are ingested but returns to a normal level after 120 minutes.
b. It increases rapidly after carbohydrates are ingested and stays greatly elevated even after 120 minutes.
c. It does not increase after carbohydrates are ingested and stays at a low level until the next meal.
d. It increases rapidly after carbohydrates are ingested but returns to a normal level after 30 minutes.
b. It increases rapidly after carbohydrates are ingested and stays greatly elevated even after 120 minutes.
Which of the following is not a classic symptom of type 1 diabetes?
a. Polyuria
b. Polydipsia
c. Polyphagia
d. Proteinuria
d. Proteinuria
Which of the following statements is true about type 1 diabetes?
a. It is associated with an insufficient amount of insulin secreted by the pancreas.
b. It is associated with inefficient activity of the insulin secreted by the pancreas.
c. It is a more frequent type of diabetes than the non–insulin-dependent diabetes (type 2).
d. Good control of this disease will eliminate complications in the future.
a. It is associated with an insufficient amount of insulin secreted by the pancreas.
What can be the result of uncontrolled elevated blood glucose?
a. Coma from insulin shock
b. Diabetic coma
c. Ketones in the urine
d. Both b and c
d. Both b and c
Gestational diabetes can occur during pregnancy in some women. Which of the following can occur for a significant number of these women?
a. Can develop type 1 diabetes at a later date
b. Can develop type 2 diabetes at a later date
c. Continue to manifest signs of diabetes after delivery
d. No effect
b. Can develop type 2 diabetes at a later date
The level of glycosylated hemoglobin in a diabetic patient reflects which of the following?
a. Blood glucose concentration at the time blood was collected
b. Average blood glucose concentration over the past week
c. Average blood glucose concentration over the past 2 to 3 months (life span of a red cell)
d. More than one of the above
c. Average blood glucose concentration over the past 2 to 3 months (life span of a red cell)
A sweat chloride result of 50mmol/L is obtained for an adult patient who has a history of respiratory problems. What would be the best interpretation of these results, based on known reference values?
a. Normal sweat chloride, not consistent with cystic fibrosis
b. Marginally elevated results, borderline for cystic fibrosis
c. Elevated results, diagnostic of cystic fibrosis
d. Normal sweat chloride, consistent with cystic fibrosis
b. Marginally elevated results, borderline for cystic fibrosis
Which of the following electrolytes is the chief cation in the plasma, is found in the highest concentration in the extravascular fluid, and has the main function of maintaining osmotic pressure?
a. Potassium
b. Sodium
c. Calcium
d. Magnesium
b. Sodium
Analysis of a serum specimen gives a potassium result of 6.0mmol/L. Before the result is reported to the physician, what additional step should be taken?
a. The serum should be observed for hemolysis; hemolysis of the red cells will shift potassium from the cells into the serum, resulting in a falsely elevated potassium value.
b. The serum should be observed for evidence of jaundice; jaundiced serum will result in a falsely elevated potassium value.
c. The test should be run again on the same specimen.
d. Nothing needs to be done; simply report the result.
a. The serum should be observed for hemolysis; hemolysis of the red cells will shift potassium from the cells into the serum, resulting in a falsely elevated potassium value.
The anion gap can be increased in patients with:
a. Lactic acidosis
b. Toxin ingestion
c. Uremia
d. More than one of the above
d. More than one of the above
Calculation of the anion gap is useful for quality control for:
a. Calcium
b. Tests in the electrolyte profile (sodium, potassium, chloride, and bicarbonate)
c. Phosphorus
d. Magnesium
b. Tests in the electrolyte profile (sodium, potassium, chloride, and bicarbonate)
Ninety percent of the carbon dioxide present in the blood is in the form of:
a. Bicarbonate ions
b. Carbonate
c. Dissolved CO2
d. Carbonic acid
a. Bicarbonate ions
Metabolic acidosis:
a. ↓ c HCO3−
b. ↑ c HCO3−
c. ↑ Pco2
d. ↓ Pco2
Key: cHCO3− , Cytoplasmic bicarbonate; Pco2, partial pressure of carbon dioxide.
a. ↓ c HCO3−
Metabolic alkalosis:
a. ↓ c HCO3−
b. ↑ c HCO3−
c. ↑ Pco2
d. ↓ Pco2
Key: cHCO3− , Cytoplasmic bicarbonate; Pco2, partial pressure of carbon dioxide.
b. ↑ c HCO3−
Respiratory acidosis:
a. ↓ c HCO3−
b. ↑ c HCO3−
c. ↑ Pco2
d. ↓ Pco2
Key: cHCO3− , Cytoplasmic bicarbonate; Pco2, partial pressure of carbon dioxide.
c. ↑ Pco2
Respiratory alkalosis:
a. ↓ c HCO3−
b. ↑ c HCO3−
c. ↑ Pco2
d. ↓ Pco2
Key: cHCO3− , Cytoplasmic bicarbonate; Pco2, partial pressure of carbon dioxide.
d. ↓ Pco2
Nitrogen is excreted principally in the form of:
a. Creatinine
b. Creatine
c. Uric acid
d. Urea
d. Urea
The main waste product of protein metabolism is:
a. Creatinine
b. Creatine
c. Uric acid
d. Urea
d. Urea
The protein content of the diet will affect primarily the test results for:
a. Creatinine
b. Creatine
c. Uric acid
d. Urea or urea nitrogen
d. Urea or urea nitrogen
Creatinine concentration in the blood has a direct relationship to:
a. Muscle mass
b. Dietary protein intake
c. Age and gender
d. More than one of the above
d. More than one of the above
In the Jaffe reaction, a red-orange chromogen is formed when creatinine reacts with:
a. Picric acid
b. Biuret reagent
c. Diacetyl monoxime
d. Both a and b
a. Picric acid
Creatinine clearance is used to assess the:
a. Glomerular filtration capabilities of the kidneys
b. Tubular secretion of creatinine
c. Dietary intake of protein
d. Glomerular and tubular mass
a. Glomerular filtration capabilities of the kidneys
Expected creatinine clearance for a patient with chronic renal disease would be:
a. Very low; renal glomerular filtration is functioning normally.
b. Normal; renal glomerular filtration is functioning normally.
c. Very high; renal glomerular filtration is not functioning normally.
d. Very low; renal glomerular filtration is not functioning normally
d. Very low; renal glomerular filtration is not functioning normally
A serum creatinine result of 6.6mg/dL is most likely to be found in conjunction with which of the following other laboratory results?
a. Urea, 15mg/dL
b. Urea, 85mg/dL
c. Urea nitrogen, 10mg/dL
d. Urea nitrogen/creatinine ratio, 15
b. Urea, 85mg/dL
A urea nitrogen result for a serum sample is reported as 10mg/dL. Calculate the concentration of urea for this sample, using the following information: the chemical formula for urea is NH2CONH2 (atomic weights: carbon 12, oxygen 16, nitrogen 14, hydrogen 1). The urea concentration for this sample is:
a. 28mg/dL
b. 21mg/dL
c. 92mg/dL
d. 43mg/dL
b. 21mg/dL
Testing blood from a patient with acute glomerulonephritis would most likely result in which of the following laboratory findings?
a. Decreased creatinine
b. Decreased urea
c. Increased glucose
d. Increased creatinine
d. Increased creatinine
Uric acid is the final breakdown product of which type of metabolism?
a. Urea
b. Glucose
c. Purine
d. Bilirubin
c. Purine
Which of the following lipid results would be expected to be falsely elevated in a blood specimen drawn from a nonfasting patient?
a. Total cholesterol
b. Triglycerides
c. HDL cholesterol
d. More than one of the above
d. More than one of the above
Blood is collected from a patient who has been fasting since 3 AM; the collection time is 7 am. Which of the following tests would not give a valid test result?
a. Cholesterol
b. Triglycerides
c. Total bilirubin
d. Either A or B
d. Either A or B
Which of the following laboratory values is considered a positive risk factor for the occurrence of coronary heart disease?
a. HDL cholesterol >60mg/dL
b. HDL cholesterol <35mg/dL
c. LDL cholesterol <130mg/dL
d. Total cholesterol <200mg/dL
b. HDL cholesterol <35mg/dL
Noting the appearance of plasma or serum can give important preliminary findings about lipid levels in the blood when it is collected from a fasting patient. When the specimen appears opaque and milky (lipemic), what is the approximate expected level of triglycerides in the sample?
a. Within the normal range; test is unaffected by meals.
b. From 200 to 300mg/dL.
c. Greater than 600mg/dL.
d. No preliminary findings can be made from observation of the serum.
c. Greater than 600mg/dL.
When a hyperlipidemic condition exists for a sufficient time, it may be associated with the development of which of the following conditions?
a. Obesity
b. Diabetes mellitus
c. Atherosclerosis
d. Viral hepatitis
c. Atherosclerosis
In what major organ of the body is the majority of the body’s cholesterol synthesized?
a. Heart
b. Pancreas
c. Gallbladder
d. Liver
d. Liver
The National Cholesterol Education Program has established cutoffs for total cholesterol and LDL cholesterol to define persons at high risk for coronary heart disease later in life. What is the cutoff for a desirable LDL cholesterol concentration?
a. <130 mg/dL
b. <160 mg/dL
c. <200 mg/dL
d. <300 mg/dL
a. <130 mg/dL
Which of the following is considered a primary risk factor for the development of coronary heart disease later in life?
a. Cigarette smoking
b. Stress
c. Diabetes mellitus
d. Lack of exercise
a. Cigarette smoking
Which of the following is considered a secondary risk factor for the development of coronary heart disease later in life?
a. Cigarette smoking
b. Increased HDL cholesterol
c. Decreased HDL cholesterol
d. Obesity
d. Obesity
In analyzing cardiac markers, which marker increases first?
a. Myoglobin
b. CK-MB fraction
c. Troponin T
d. Troponin I
a. Myoglobin
Which cardiac marker persists at the highest concentration for the longest length of time?
a. Myoglobin
b. CK-MB fraction
c. Troponin T
d. Troponin I
c. Troponin T
Which of the following enzymes is found primarily in the liver?
a. Aspartate transaminase
b. Alkaline phosphatase
c. Alanine transaminase
d. γ-Glutamyltransferase
c. Alanine transaminase
Elevated concentrations of serum amylase and lipase are often seen in:
a. Acid reflux disease
b. Gallstones
c. Acute pancreatitis
d. Acute pharyngitis
c. Acute pancreatitis
What is the classic symptom or manifestation of liver disease?
a. Hemolysis of red cells
b. Jaundice
c. Kernicterus
d. Formation of gallstones
b. Jaundice
In an adult, if total bilirubin value is 3.1mg/dL and conjugated bilirubin is 1.1mg/dL, what is the unconjugated bilirubin value?
a. 2.0 mg/dL
b. 4.2 mg/dL
c. 1.0 mg/dL
d. 3.4 mg/dL
a. 2.0 mg/dL
A rapid buildup of unconjugated bilirubin in a newborn can result in kernicterus, which is an accumulation of bilirubin in the:
a. Heart tissue
b. Liver cells
c. Brain tissue
d. Kidney tissue
c. Brain tissue
Impairment of conjugation of bilirubin by the liver cells is:
a. Prehepatic jaundice
b. Hepatic jaundice
c. Posthepatic jaundice
d. None of these phases
b. Hepatic jaundice
Transport defects involving release of the bilirubin bound to plasma albumin to the liver cell for conjugation with glucuronide is:
a. Prehepatic jaundice
b. Hepatic jaundice
c. Posthepatic jaundice
d. None of these phases
a. Prehepatic jaundice
Defect in transporting the conjugated bilirubin out of the liver cells and into the bile fluid is:
a. Prehepatic jaundice
b. Hepatic jaundice
c. Posthepatic jaundice
d. None of these phases
c. Posthepatic jaundice
In which of the following conditions resulting in jaundice is there an increase in both conjugated and unconjugated bilirubin?
a. Hemolysis of red cells
b. Viral hepatitis
c. Obstruction from gallstones
d. Constriction of biliary tract from neoplasm
b. Viral hepatitis
In which of the following conditions resulting in jaundice is there an increase primarily in unconjugated bilirubin?
a. Increased hemolysis of red cells
b. Viral hepatitis
c. Biliary obstruction
d. Cirrhosis of the liver
a. Increased hemolysis of red cells
In a premature newborn, a deficiency of what enzyme can affect the conjugation of bilirubin glucuronide in the liver?
a. Glucuronosyltransferase
b. Aspartate transaminase
c. Alanine transaminase
d. γ-Glutamyltransferase
a. Glucuronosyltransferase
Hormones secreted by the thyroid include:
a. Thyroxine
b. Triiodothyronine
c. Insulin
d. Both a and b
d. Both a and b
Tumor markers include:
a. Carcinoembryonic antigen (CEA)
b. Alpha fetoprotein
c. Beta subunit of human chorionic gonadotropin
d. All the above
d. All the above
In therapeutic drug monitoring assay, it is extremely important to test the specimen:
a. Exactly 8 hours after the drug is ingested
b. At the established peak and/or trough intervals
c. For competing antibodies to the drug
d. Before the establishment of a steady state
b. At the established peak and/or trough intervals
Drugs of abuse include:
a. Acetaminophen
b. Salicylic acid
c. Amphetamines
d. Antibiotics
c. Amphetamines
The blood pH is:
a. Alkaline
b. Acidic
c. Very Acidic
d. Neutral
a. Alkaline
The following results were obtained:
pH = 7.6
PCO2 = 20mm Hg
PO2 = 128mm Hg
HCO3− = 15mmol/L
Na+ = 138mmol/L
K+ = 3.9mmol/L
Cl− = 107mmol/L
TCO2 = 24mmol/L
The most likely condition is:
a. Blood specimen is not delivered on ice promptly to the laboratory.
b. Blood specimen contained air bubbles.
c. Patient is in a state of partially compensated metabolic alkalosis.
d. Patient is in a state of partially compensated respiratory alkalosis.
d. Patient is in a state of partially compensated respiratory alkalosis.
