Biochem exam

Question 1

Liver cirrhosis is caused by:
a) Autoimmune Primary Biliary cirrhosis
b) alpha1-antitrypsin deficiency
c) Haemochromatosis
d) All of the above

Answer 1

d) All of the above

Question 2

Most sensitive liver injury marker?
a) Albumin
b) Aminotransferases
c) Bilirubin
d) Creatine kinase

Answer 2

b) Aminotransferases

Question 3

Which are fibrosis effector cells?
a) Stellate cells
b) Sinusoidal cells
c) Epithelial cells
d) Parenchymal cells

Answer 3

a) Stellate cells

Question 4

Which is a myocardial infarction specific cardiac biomarker?
a) Creatine kinase (BB)
b) Creatine kinase (MM)
c) Troponin 1
d) Lactate dehydrogenase (LDH5)

Answer 4

c) Troponin 1

Question 5

In primary hypercholesterolaemia the blood cholesterol in heterozygotes is:
a) >7.8 mmol/l
b) >15.5 mmol/l
c) 6.0 mmol/l
d) >3.8 but >6.5 mmol/l

Answer 5

a) >7.8 mmol/l

Question 6

Which of the following is not a feature of non-alcoholic steatohepatitis (NASH)?
a) Hepatocyte Ballooning
b) Steatosis
c) Lymphoid follicles
d) Perisinusoidal inflammation

Answer 6

c) Lymphoid follicles

Question 7

Increases in intracellular free cholesterol result in:
a) Decreased HMG CoA (hydroxymethylglutaryl-conenzyme A) reductase
b) Increased HMC CoA reductase
c) Decreased ACAT (Acetyl-coenzyme A acetyltransferase)
d) Increased LDL receptor synthesis

Answer 7

a) Decreased HMG CoA (hydroxymethylglutaryl-conenzyme A) reductase

Question 8

A 4-year-old child was reviewed at the children’s hospital with hepatosplenomegaly and mental retardation. Biopsy reveals accumulation of sphingomyelin. What is the disease?
a) Gaucher’s
b) Niemann Pick’s
c) Krabbe’s
d) Tay Sach’s

Answer 8

b) Niemann Pick’s

Question 9

Treatment regimes for type II diabetics can include:
a) Metformin
b) Thiazolidinediones
c) Sulfonylureas
d) All of the above

Answer 9

d) All of the above

Question 10

The non-enzymatic glycosylation product haemoglobin A1C reflects glycaemia:
a) Over the last 2 months
b) Over the last 3 weeks
c) Over the last 5 days
d) Over the last 6 months with macro-albumin urea

Answer 10

a) Over the last 2 months

Question 11

Statins are first line drugs for lowering LDL-cholesterol and their major mechanism of action is:
a) Inhibit VLDL synthesis and secretion
b) Increase cholesterol oxidation
c) Decrease in ACAT activity
d) HMG CoA reductase inhibitors

Answer 11

d) HMG CoA reductase inhibitors

Question 12

Respiratory alkalosis develops when respiratory activity:
a) Decreases plasma pO2 to below to normal levels
b) Raises plasma pCO2 to above to normal levels
c) Does not affect pCO2 levels
d) Lowers plasma pCO2 to below to normal levels

Answer 12

d) Lowers plasma pCO2 to below to normal levels

Question 13

As a result of the aging process, changes in the ability to regulate pH through renal compensation is the result of:
a) A reduction in the rate of insensible perspiration
b) A reduction in the number of functional nephrons
c) Increased glomerular filtration
d) Increased ability to concentrate urine

Answer 13

b) A reduction in the number of functional nephrons

Question 14

Which of the following patients is at most risk for hypomagnesaemia:
a) A 55-year-old chronic alcoholic
b) A 57-year-old with hyperthyroidism
c) A patient reporting overuse of antacids and laxatives
d) A 25-year-old suffering from hypoglycaemia

Answer 14

a) A 55-year-old chronic alcoholic

Question 15

The haemoglobin buffer system helps prevent drastic alterations in pH when:
a) The plasma pCO2 is constant
b) RBC production is decreasing
c) The plasma pCO2 is rising or falling
d) Haemoglobin production is increasing

Answer 15

c) The plasma pCO2 is rising or falling

Question 16

Which patient is at more risk of an electrolyte imbalance?
a) An 8-month-old with a fever of 40oC and diarrhoea
b) A 55-year-old diabetic with nausea and vomiting
c) A 5-year-old with Respiratory syncytial virus (RSV)
d) A healthy 87-year-old with intermittent episodes of gout

Answer 16

a) An 8-month-old with a fever of 40oC and diarrhoea

Question 17

A 48- year-old male with renal failure, missed his dialysis and was feeling sick, what could be the reason?
a) Metabolic acidosis
b) Metabolic alkalosis
c) Respiratory acidosis
d) Respiratory alkalosis

Answer 17

**a) Metabolic acidosis **

Question 18

Which of the following laboratory results below indicates compensated metabolic alkalosis?
a) Low pCO2, normal bicarbonate, high pH
b) Low pCO2, low bicarbonate, low pH
c) High pCO2, normal bicarbonate, low pH
d) High pCO2, high bicarbonate, high pH

Answer 18

d) High pCO2, high bicarbonate, high pH

Question 19

Which of the following does not cause hypokalaemia:
a) Renal failure
b) An increase in the pH of the extracellular fluid (ECF)
c) Excessive aldosterone secretion
d) The administration of diuretic drugs

Answer 19

a) Renal failure

Question 20

Which patient below would have a potassium level of 5.5 (normal potassium levels are 3.5 to 5.1):
a) A 76-year-old who reports taking furosemide four times a day
b) A patient with Addison’s disease
c) A 55-year-old woman who have been vomiting for 3 days consistently
d) A patient with liver failure

Answer 20

b) A patient with Addison’s disease

Question 21

Which of the following liver function tests (LFTs) are specific for cirrhosis:
a) Alkaline phosphatase
b) Gamma-glutamyl transpeptidase
c) Bilirubin
d) None of the above alternatives

Answer 21

d) None of the above alternatives

Question 22

In the differential diagnosis of cholestatic or hepatocellular (hepatic) jaundice which of the following biochemical measurements are important:
a) Alkaline phosphatase
b) γ-Glutamyl transpeptidase (γ-GT)
c) Aspartate aminotransferase (AST)
d) All of the above options

Answer 22

d) All of the above options

Question 23

Which of the following is the most useful cardiac biomarker of myocardial infarction (MI):
a) Creatine kinase
b) Lactate dehydrogenase (LDH5)
c) Alanine aminotransferase
d) α 1-antitrypsin

Answer 23

a) Creatine kinase

Question 24

Type I diabetes is characterised by:
a) Islet cell autoantibodies
b) Normal pancreatic β-cells
c) Decreased ketosis
d) Variable insulin deficiency

Answer 24

a) Islet cell autoantibodies

Question 25

The oral glucose tolerance test (OGTT) is diagnostic for diabetes when: a) The blood glucose is 8 mmol/l at 2 hr following the OGTT b) The blood glucose at 2 hr greater than 11 mmol/l c) The blood glucose is 8 mmol at two time points and at 2 hr d) The blood glucose is 8 mmol/l at all time points but below 11 mmol/l at 2 hr

Answer 25

**b) The blood glucose at 2 hr greater than 11 mmol/l**

Question 26

Thyroid stimulating hormone (TSH), tri-iodothyronine (T3) and Thyroxine (T4) measurements are important in the biochemical investigation of: a) Graves’ disease b) Hyperthyroidism c) Hypothyroidism d) All of the above

Answer 26

**d) All of the above**

Question 27

A 19-year-old male presented with tendon xanthoma and had a plasma cholesterol level of 20 mmol/l, triglyceride of 0.9 mmol/l and electrophoresis showed increased β- lipoprotein (LDL). What do these results indicate: a) Primary hypercholesterolaemia b) A homozygotic form of hypercholesterolaemia c) A heterozgotic form of hyperchylomicronaemia d) Hyperchylomicronaemia

Answer 27

**b) A homozygotic form of hypercholesterolaemia**

Question 28

Cholesterol is transported from extra hepatic tissue to the liver by which of the following lipoproteins? a) Chylomicrons b) HDL c) LDL d) VLDL

Answer 28

**b) HDL**

Question 29

Over 1000 mutations have been described for the LDL receptor, where do the majority occur: a) Within the EGF precursor homology domain b) Within the signal sequence c) Within the membrane spanning domain d) Within the cytoplasmic domain

Answer 29

**a) Within the EGF precursor homology domain**

Question 30

A 15-year-old boy is admitted to the A&E department of a local hospital. He is fatigued, with ketones in his urine. These clinical and laboratory findings indicate: a) Diabetic ketoacidosis (DKA) condition b) A hyperosmolar non-ketotic (HONK) condition c) Hyperglycaemia d) Kidney failure

Answer 30

**a) Diabetic ketoacidosis (DKA) condition**

Question 31

Chronic diarrhoea causes a severe loss of bicarbonate ions, resulting in: a) Metabolic alkalosis b) Respiratory alkalosis c) Respiratory acidosis d) Metabolic acidosis

Answer 31

**d) Metabolic acidosis**

Question 32

The major contributors to the osmolarities of the extracellular fluid (ECF) and the intracellular fluid (ICF) are: a) C hloride and bicarbonate b) ADH and aldosterone c) Sodium and potassium d) Renin and angiotensin

Answer 32

**c) Sodium and potassium**

Question 33

Which of the following is most appropriate for a female suffering from type 1 diabetes with a blood pH of 7.2, HCO3 of 17 mmol/L and pCO2 of 20 mm Hg? a) Metabolic acidosis b) Metabolic alkalosis c) Respiratory acidosis d) Respiratory alkalosis

Answer 33

**a) Metabolic acidosis **

Question 34

After obtaining an Electrocardiography (ECG) on a patient you notice that an ST wave depression is present along with an inverted T wave and prominent U wave. What analyte would be the cause of this finding (normal potassium levels are 3.5 to 5.1): a) Potassium level of 2.2 b) Potassium level of 5.6 c) Magnesium level of 2.3 d) Phosphorus level of 2.0

Answer 34

**a) Potassium level of 2.2**

Question 35

Which of the following compounds can act as an acid when dissolved in water? a) H2CO3 b) H2PO4- c) NH4+ d) All of the above

Answer 35

**d) All of the above**

Question 36

An 87-year-old woman had a bad cold. After two weeks she complained that, “It’s gone to my chest, can’t stop coughing and it feels tight in my chest and I am unable to breathe!” What could be the possible reason? a) Metabolic acidosis b) Metabolic alkalosis c) Respiratory acidosis d) Respiratory alkalosis

Answer 36

**c) Respiratory acidosis**

Question 37

Under normal circumstances, during respiratory acidosis the chemoreceptors monitoring the pCO2 of the plasma and CSF will eliminate the problem by: a) Decrease in pulmonary ventilation rates b) Decrease in the breathing rate c) Breathing into a small paper bag d) An increase in pulmonary ventilation rate

Answer 37

**d) An increase in pulmonary ventilation rate**

Question 38

A mismatch between carbon dioxide generation in peripheral tissues and carbon dioxide excretion in the lungs is a: a) Severe bicarbonate loss b) Condition known as ketoacidosis c) Metabolic acid-base disorder d) Respiratory acid-base disorder

Answer 38

**d) Respiratory acid-base disorder**

Question 39

When a normal pulmonary response does not reverse respiratory acidosis, the kidneys respond by: a) Increasing the reabsorption of hydrogen ions b) Increasing the rate of hydrogen ion secretion c) Increased loss of bicarbonate ions d) Decreasing the rate of hydrogen ion secretion

Answer 39

**b) Increasing the rate of hydrogen ion secretion**

Question 40

Which of the following are not associated with metabolic alkalosis? a) Prolonged vomiting b) Hypokalaemia c) Hyperaldosteronism d) Hypoaldosteronism

Answer 40

**d) Hypoaldosteronism**

Question 41

Which of the following options are associated with metabolic acidosis? a) A raised plasma HCO3- b) A decreased blood pCO2 c) It can be caused by hyperaldosteronism d) It is always associated with a normal anion gap

Answer 41

**b) A decreased blood pCO2**